Mysmena wawuensis, a new species of tiny spider from Sichuan. Credit: Shuqiang Li

Dear Mr M. wawuensis,

Thank you for your application to study at the Academy of Terrors and General Unpleasantness. As you know, the Academy can only accept a very limited number of students each year, and unfortunately we cannot offer you a place this coming semester. This decision was based on a rigorous assessment from our admissions committee, who were very impressed by your academic achievements, but ultimately decided that your modest size unequivocally undermines your potential as an arachnid to be either terrifying or unpleasant, both of which are essential requirements of the Academy.

However, there are a number of fine institutions that I’m sure would be thrilled to have you, considering the achievements and qualities outlined in your application. There’s the College of Difficult-to-Sees and the Academy of Cute-For-As, and while the Society of Invisibles is notoriously secretive, it might be worth tracking them down. I would be happy to write you a recommendation based on the fact that yours was the only application in the history of the Academy of Terrors that required a magnifying glass to read.

I wish you all the best,

Professor Moistcrust Skinfingers

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Two new species of spider no bigger than a grain of sand have been discovered, their strange, bulbous bodies hidden from scientists for years under the moist leaf litter of China’s dense forests.

At just 1.01 mm and 0.75 mm long respectively, the newly described species Trogloneta yuensis and Mysmena wawuensis aren’t winning any visibility contests. They belong to the little-studied family Mysmenidae, which includes 123 known species of minute orb-weaving spiders spread all across the globe in caves, forests and rainforests, wherever it’s humid and tropical.

Thanks to their webs, which are about the size of an apricot, Yucheng Lin from China’s Sichuan University and Shuqiang Li from the Chinese Academy of Sciences in Beijing found one T. yuensis in the Jinyun Mountain Nature Reserve in Chongqing, and two M. wawuensis spiders in the Wawu Mountain National Forest Park of Sichuan. Sichuan is the most important place in the world for giant pandas, with 76% of the global population living in its dense and misty forests. Ten giant pandas live in the Wawu Mountain Park, along with red pandas, 30 species of reptiles and these tiny M. wawuensis spiders.

The male Trogloneta yuensis, showing its spotted body pattern and huge pedipalps. Credit: Shuqiang Li

Lin and Li describe the spiders, with their disproportionately large and spherical posteriors, in a recent edition of Zookeys. Considered one of the smallest known species of spider, M. wawuensis has a distinctive black body speckled ever so slightly with yellow, and its golden legs are about a millimetre long. The males are smaller than the females, with bodies just 0.60 mm long. Meanwhile, T. yuensis is almost the opposite – their huge, yellow posteriors patterned with feathery black spots. The males of both species have very large pedipalps, which are the two hairy, arm-like appendages that sit between the foremost pair of legs and act like antennae.

Patu digua, considered the smallest species of spider in the world. Credit: Facundo M. Labarque, Museo Argentino de Ciencias Naturales

A bulbous body seems to have served these tiny spiders well, and they share the trait with what is considered the smallest spider in the world, Patu digua. This Columbian native is just 0.37 mm long in the females, and the males – none of which have ever been found – are likely to be even tinier.

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Southern bottletail squid can range in colour from rusty orange and yellow to a pale white. Credit: Julian Finn, Museum Victoria

Sperm consumption has been reported for the first time in female southern bottletail squid, and it looks like they’re using this nutrient-rich ejaculate to maintain steady egg production and healthy bodies.

Southern bottletail squid (Sepiadarium austrinum) are found in the shallow, coastal waters of southern Australia, and grow to only about 4 cm long. They spend their days buried in the sand, only coming out at night to feed on small crustaceans, and they’ll defend themselves by releasing a large amount of mucous at their predators.

“Nothing had been done on them before, with not a single scientific paper in the literature,” says Benjamin Wegener from Monash University in Melbourne, lead author of a Biology Letters paper published today about the mating habits of this tiny, translucent species. “Given we were starting from scratch, I decided the best way to get a handle on their reproductive behaviour was to put a male and female together and see if they mate. The male immediately grabbed the female and they went for it.”

Eschewing any obvious form of courtship, southern bottletail squid will mate head to head, the male depositing sperm packages called spermatophores onto the female’s buccal cavity – an external, fleshy pouch located just below the mouth. The female will then extract mature eggs from her mantle and pass them against the stored spermatophores before depositing them, now fertilised, at the base of seagrasses, seaweeds or rock crevices. The females can store spermatophores in their buccal cavities for up to three weeks after an encounter with a male. They’ll also scrape a number of these spermatophores off the buccal cavity membrane and eat them.

Late last year, Wegener and his colleagues discovered that small females consumed significantly more spermatophores than the large ones, and the males showed a distinct preference for the large females. This could be one of a series of possible strategies used by both the males and the females to influence the paternity of the offspring, they suggested, because by choosing the larger females that consume less spermatophores, the males are effectively lessening this threat to their potential offspring.

But the researchers also found that this preference for larger females didn’t influence the males to impart any less of their spermatophore stores to the smaller, ‘hungrier’ females, and this suggested that by eating spermatophores, the smaller females might be able to produce higher numbers of healthier offspring than they could otherwise manage.

A pair of southern bottletail squid mating. Credit: Kade Mills

To test this, the team, which included evolutionary biologist Devi Stuart-Fox from the University of Melbourne and Mark Norman from Museum Victoria, observed the mating habits of 51 southern bottletail squid collected in Port Phillip Bay. The males were fed radioactive amphipods (small shrimp-like crustaceans) until they reached sexual maturity, at which point they started to produce radioactive spermatophores. When the females ate the spermatophores, and all of them did, the researchers could trace the radioactivity levels to see how they had been incorporated around the body to deliver nutrients to various tissues and unfertilised eggs. “Even though Mark had mentioned that [spermatophore consumption] might be a possibility, actually seeing something for the first time, and realising you’re probably the first person in the world to have actually done so… that was pretty special,” says Wegener.

During the day, the little southern bottletail squid buries itself in the sand to hide from predators, only emerging at night to feed. Credit: Julian Finn, Museum Victoria

The experiments also revealed more about how a complex battle over paternity was being waged between the males and the females. The males could attempt to scoop a rival’s spermatophores out of the female’s buccal cavity and replace it with his own, and they appear to minimise spermatophore consumption by strategically depositing their ejaculates in an area of the female’s buccal cavity that she couldn’t reach – “prime real estate”, says Wegener – near the base of the beak. This was confirmed by the presence of numerous spermatophores lining the base of the beak when the females were dissected within three weeks of mating.

They also appear to know that it is advantageous to mate with a female that is closest to being in an egg-laying condition, because if she’s not, they could be unwittingly helping a rival to produce offspring instead. “These females are using the nutrients from males to develop her unfertilised eggs,” says Wegener. “If she doesn’t lay eggs soon after mating, the males could completely miss out on fertilising her eggs, and instead act as a contributor to the next male that comes along.”

There is also the potential for some female control in the paternity of her offspring after copulation, with the possibility that she is selectively eating the spermatophores of less desirable mates and saving those of the more attractive ones, in a similar manner to the way male gulf pipefish selectively abort the embryos of unattractive females to consume their nutrients, but this has yet to be explored. What Wegener is now working on is the possibility that the males are taking advantage of any opportunity to rid themselves of lower quality spermatophores, which would help to explain why they deposit the majority of their spermatophore stores with each sexual encounter, regardless of how much of it is likely to be eaten by his mate.

Papers cited:

Benjamin J. Wegener, Devi Stuart-Fox, Mark D. Norman and Bob B. M. Wong (2013). Spermatophore consumption in a cephalopod
Biology Letters

Wegener, B., Stuart-Fox, D., Norman, M., & Wong, B. (2013). Strategic male mate choice minimizes ejaculate consumption Behavioral Ecology, 24 (3), 668-671 DOI: 10.1093/beheco/ars216

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A green anole lizard with a bright red dewlaps. Credit: Steven2005; Flicker (flickr.com/photos/steven2005)

Devi Stuart-Fox is an evolutionary biologist at the University of Melbourne who has spent the past decade investigating colour change in lizards. She’s now leading an international team of researchers in an investigation into how they achieve colour change, why they do it, and what it costs them. I had a chat to her about what she’s discovered, and what she hopes to discover, about the incredibly complex language of colour change in nature.

Your research showed that the primary use of colour change in chameleons isn’t camouflage. What is it?

There are a lot of species of chameleon, and some have really advanced capacities for colour change, and in others it’s really very limited. So the big question was, why has this ability evolved to such a remarkable degree in some species and not in others?

What we were able to show is the species that do change colour the most actually have the most conspicuous social displays. So there’s been selection for them to use these really bright, flashy colours in their communication and social displays, therefore there was selection on their ability to change colour. We suggested that the ability to change colour evolved for that reason, rather than simply for camouflage. Because why change colours, why not just be very camouflaged against your backgrounds?

We were wondering whether the ability to change colour could be related to the number of different backgrounds they would need to match, or the particular habitat they are found in. We found that there is no relationship, so that’s why we said it hasn’t been driven by camouflage. They obviously use it for camouflage – they match very well – but it’s a limited range of colours they have to match. Whereas in their social displays when they change colours, they’ve got pinks and oranges, greens and blues, and a wide range of ultraviolet colours that are visible to chameleons but not to us.

Devi Stuart-Fox with a Central bearded dragon. Credit: L’Oréal Australia and sdpmedia.com.au

Do bearded dragons use colour change in a similar way?

Females use colour to signal whether they’ll accept courtship or aggressively reject male advances, and the males use it in territorial displays and also in courtship displays to female. We don’t know what specific colours mean, in some cases dark colours can be a symbol of submission, but in other cases, like the black beard in [Central bearded dragon] males, it’s a symbol of dominance. So different colours mean different things in different contexts.

A female Lake Eyre dragon flips over to stop unwanted males from mating with her. Credit: Devi Stuart-Fox

But the females are only receptive for a very brief period of time, and the males will just continuously harass them. So to escape from that, the females will, as a last resort, flip onto their backs, [which means] they can’t actually mate, and they show these bright orange belly patches. The belly patches don’t seem to attract the attention of predators, because firstly, predators are quite rare out on these salt pans, and secondly, we showed through experiments that predators seem to avoid flipped over females with bright orange patches because they’ve never seen anything like it. They don’t even recognise them as potential prey. And when the females are pregnant, the size of the patches increase. So they can use these orange colours to signal that they’re receptive, or when they combine it with the flipping over behaviour, to signal that they’re not receptive, to try and avoid harassment. So the colours can be used in very different contexts when they’re combined with different behaviours.

Central bearded dragon (Pogona vitticeps). Credit: Devi Stuart-Fox

It’s a big unknown. No one’s tried to quantify the metabolic or physiological costs of colour change. We know that it involves the movement of pigments in the cells, and that can be controlled by hormones, and in chameleons it’s controlled directly by signals from the brain by neurotransmitters. But it’s very hard to test because what you have to do is have lizards that are changing colour a lot and look at things like metabolic rate or loss of body condition versus lizards that aren’t allowed to change colour at all. We assume that it’s costly, because otherwise, why hasn’t it evolved more widely?

I love my job because I feel like it takes me to all sorts of interesting parts of the world. I’m just totally fascinated by all the amazing ornaments and colours that you see in nature, every time you watch a wildlife documentary, there are just so many bizarre ornaments and behaviours and that’s what really grabs me and I’ve been lucky enough to make a career studying it.

In lizards one of the most amazing things are the gliding lizards that you get through Southeast Asia with rib cages that extend out from their sides and are covered by a gliding membrane so they can glide phenomenal distances. I got a National Geographic grant to work on those gliding lizards because they have quite colourful wings and dewlaps – which is the male throat fan that they signal madly to each other with. You get lots of species co-occurring in the gliding lizards, so it could have to do with recognising members of their own species. It could be also to do with – and this is what we’re testing – some colours working better as a signal in different habitats. A green dewlap in a green forest doesn’t work very well if you’re trying to draw the attention of another lizard, and in fact, ultraviolet colours don’t work so well because there’s not much ultraviolet light in deep, dark forests. Whereas ultraviolet colours and black, work really well in open environments and things like reds, oranges and yellows work really well in closed environments, because the forest environments are quite rich in light in those wavelengths.

An Anole lizard with an incredible colour display. Credit: Ruan Kendell; Flickr (flickr.com/photos/shearwater)

It was a big surprise, actually. It’s a prize, so it’s not specifically research money. I’ve got two small kids, and I do quite field-intensive research, so I drag my kids along on field trips, and my husband often comes too. So our plan is to use the money to help with those costs. I’m very lucky to be able to do that, I prefer not to be away from my kids for extended periods, so it is a real luxury to be able to take them on field trips. It really struck me when I was in France for the Women in Science Week, there were 15 recipients of the Early Career Fellowships, and they’re mostly women from developing countries going to do a fellowship in developed countries and five of the 15 already had kids, and several of them were leaving them behind with their [grand]parents. There’s so much talk about combining career with family and the reality is that it doesn’t really happen for a lot of women. I just feel really fortunate to have been able to combine family and career without having to be away for my kids for long periods.

Papers cited:

Chen, I., Stuart-Fox, D., Hugall, A., & Symonds, M. (2012). SEXUAL SELECTION AND THE EVOLUTION OF COMPLEX COLOR PATTERNS IN DRAGON LIZARDS Evolution, 66 (11), 3605-3614 DOI: 10.1111/j.1558-5646.2012.01698.x

Jessop, T., Chan, R., & Stuart-Fox, D. (2009). Sex steroid correlates of female-specific colouration, behaviour and reproductive state in Lake Eyre dragon lizards, Ctenophorus maculosus Journal of Comparative Physiology A, 195 (7), 619-630 DOI: 10.1007/s00359-009-0437-4

Stuart-Fox, D., & Moussalli, A. (2008). Selection for Social Signalling Drives the Evolution of Chameleon Colour Change PLoS Biology, 6 (1) DOI: 10.1371/journal.pbio.0060025

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My book, Zombie birds, astronaut fish and other weird animals, is now available in the US, from Amazon and most book stores.

One of the Asiatic golden cat cubs at around 40 days old. Credit: Imke Lüders

A pair of Asiatic golden cats have been bred using artificial insemination for the first time in an effort to ensure the future of this rare and beautiful species.

Asiatic golden cats (Pardofelis temminckii) are small, nocturnal cats that live in the tropical rainforests of southeast Asia, their range stretching from China, Nepal and India to Burma, Thailand and Malaysia. They’re about two or three times the size of a house cat, the females growing to around 66 cm long (minus the tail) and 9 kg in weight, and the males are much larger at 105 cm long and 16 kg. They are shy animals that live solitary lives, fiercely maintaining large territories and only coming together briefly to mate.

The most common colouring of an Asiatic golden cat is a golden brown or fox-red, but they can also be a dark brown, grey or pale cinnamon. There is also a spotted, ocelot-like morph that is more common in China than the usual colouring, and numerous melanistic, or black, individuals have been found, particularly in Nepal. There’s even a tiny area in Sikkim, which is a small mountainous state in the Eastern Himalayan region, where melanistic Asiatic golden cats are far more common than any other morph.

The golden coat of an adult Asiatic golden cat. Credit: Karen Stout; Flickr

Because of their striking colour, in some parts of Thailand Asiatic golden cats are called “Seua fai”, meaning ‘fire tiger’, and local legend states that the burning of its fur or the eating of its flesh can drive tigers away. The Karen people of Thailand and Burma believe that carrying a single Asiatic golden cat hair will have the same effect.

Habitat destruction and a relentless fur trade over the past few decades has seen the global population of the Asiatic golden cat dwindle to the point where we don’t know how many are left in the wild, and there are just 51 individuals in captivity in Europe and Asia. Captive breeding programs are essential to the survival of the species, but because we still know very little about their reproductive biology, and because they can be extremely aggressive towards each other, breeding them can be a very difficult and dangerous exercise, all the way from courtship to birth.

A 1997 study in the International Zoo Yearbook by zoo keeper Mike Brocklehurst from the Royal Melbourne Zoological Gardens describes the extraordinary measures the zoo’s staff had to go through to breed their Asiatic golden cats, even with almost 30 years of experience. Since 1968, when the Melbourne Zoo acquired their first five Asiatic golden cats from Europe and the US, they’ve had two deaths because of male on male and female on female fights; one death during a male and female introduction; and another within an established mating pair. Brocklehurst also reports two instances of a male killing a young female after copulation, and while it never happened at Melbourne Zoo, adult males and females have also been known to cannibalise their own young. So breeding Asiatic golden cats the ‘natural’ way is never as simple as sticking two of them in a room together and hoping they get along.

A very proud Asiatic golden cat mum and her eight-week-old cub at Melbourne Zoo. Credit: Ned McLeod, Melbourne Zoo

According to Brocklehurst, their breeding process began with keeping a male and female in adjacent enclosures for 30 days, allowing them to see, smell and hear each other. Feeding was increased by 20% during this time to make them less aggressive. Then, a door is opened, allowing the pair to interact physically for just an hour a day, this period increasing over two weeks if there are no signs of aggression. If all is well, 24-hour access is finally allowed, and they have 70 days to mate before they are separated once again. This is ensure that the male doesn’t go on a killing spree if the female gives birth. If the female does not give birth after 90 days, the whole process begins again. If she does give birth, she’ll likely only have one cub.

More recently, staff at the Allwetter Zoo in Münster, Germany, were also having problems with their Asiatic golden cat breeding pair – ‘Lao’ the male and ‘Sua Fai’ the female. Lao had attacked Sua Fai, and they were worried that the next attack could be fatal. While they were unable to find another suitable mate for Sua Fai, the team was reluctant to remove such a young female from the limited breeding program, so considered breeding the pair through artificial insemination. Knowing that no one had successfully bred this species using artificial insemination before, they came up with different methods to complete the process without surgery, and relied on Sua Fai’s natural estrous cycle rather than a pre-treatment hormone program. The project was led by veterinarian Imke Lüders, a specialist in assisted reproduction techniques for zoo animals. “I had just tested a new semen collection method in lions and cheetahs in South Africa,” she says. “I think this was one of the key factors for a successful artificial insemination. Lions and cheetahs are much bigger, [but] the principles are the same.”

The mother 'Sua Fai' on day of insemination. Credit: Imke Lüders

Because they hd decided not to use a pre-treatment hormone program, the zoo staff had to observe Sua Fai closely to pick when she was in heat, which was their cue to extract the semen from Lao. In many animals, the semen required for artificial insemination is usually collected via electro ejaculation – placing electrodes into the rectum to stimulate the prostate and produce an ejaculation. But this method causes urine contamination of the sample, plus high volumes of seminal plasma, which can reduce the chances of pregancy. So instead,  Lüders’s team anesthetised Lao, causing semen to be released into the urethra, and performed and enema and transrectal ultrasound scan to visualise the prostate. They then used a urinary catheter to collect a highly concentrated, uncontaminated semen sample. The female Sua Fai was anesthetised and given a dose of hormones to induce ovulation – which only worked because the zoo staff had correctly identified that she was in heat – and the semen was inserted into her uterus. After a period of about 80 days, Sua Fai gave birth to two cubs, a male and a female, on April 7.

One of the hand-raised cubs, called 'Cat Ba', at just one day old. Credit: Imke Lüders

“Usually, Asiatic golden cats give birth to one cub, but we had twins!” says Lüders. ”However, after initial intensive maternal care, Sua Fai changed her nesting box and left one cub [the female] behind. We were very happy that she showed such a good maternal instinct in the beginning – it is not unusual that first-time mothers do not take care of their babies at all, or even eat them.”

To ensure that Sua Fai didn’t stress out and neglect her other cub, the Allwetter Zoo staff removed the female cub she left behind. “While Sua Fai is still a perfect mom to the male cub, the female was hand-raised,” says Lüders. “Both cubs are doing fine! We even place the little female back to socialise with her brother when their mum is outside. They play a lot together. I really hope they both make it, and will bring new hope for the breeding program.”

The twins are now around 40 days old. Credit: Imke Lüders

Lüders now plans to help another European zoo breed their Asiatic golden cats using this new technique, and while it may help in situations similar to Lao and Sua Fai’s, she does not think it will take the place of breeding the cats naturally. “We need to focus on their social behaviour, and on creating harmonic breeding pairs. Maybe by introducing the partners much earlier in their life. But in our case, I am still very glad we did it. It is such a great thing for the cat to raise a baby – no better enrichment possible for a captive female.”

“These cats may adapt to a variety of habitats, but they need undisturbed, intact areas in order to find prey and raise their young,” she added. “This is becoming more and more scarce in Asia. As for so many other wildlife, the chances of survival are small. For the Asiatic golden cat, I hope their size may help them to survive longer and under more severe conditions, but it is hard to predict. We do not even know how many are still out there.”

Head over to Zooborns to see more photos of how incredibly gorgeous the twins are at seven weeks old, and watch a video of the cutest one-day-old roar ever.

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Little spotted kiwi chick. Credit: © Andrew Digby

Kiwi are flightless, nocturnal birds that are native to New Zealand. There are five recognised species of kiwi, and with 400 remaining individuals, the rarest is the critically endangered Rowi (Apteryx rowi) of New Zealand’s Okarito forest. The second rarest species is the little spotted kiwi (Apteryx owenii), which has been spread over several of New Zealand’s smaller islands since becoming extinct on the mainland more than 30 years ago. The species’ steady increase from just five individuals to around 1,600 is considered so impressive, they’re the only species of kiwi not currently classified as threatened, despite how rare they are. But a new study investigating their genetic diversity has revealed that the little spotted kiwi may be in more danger than we thought.

With a length of 35 to 45 cm in males, and weighing little more than a kilogram, the little spotted kiwi is the smallest species of kiwi. It owes the second half of its name to its shaggy, mottled grey and white feathers. While their wings are negligible, they are fast runners, and they use their powerful legs and claws to defend themselves. Adults typically form monogamous pairs that can last for decades, during which time they’ll usually produce one or two chicks per year. Very little is known about the species, including at what age they become sexually mature, but it’s thought that they can live to be 100 years old.

The little spotted kiwi was once widespread on the North and South Islands that make up the mainland of New Zealand, but introduced predators such as cats, dogs and stoats, a reduced habitat and an enormous skin trade saw them decline rapidly in numbers, disappearing altogether from the North Island by 1900. During the 1980s, the little spotted kiwi was declared extinct on the South Island too. Fortunately, two populations existed on the nearby D’Urville and Kapiti Islands. D’Urville and Kapiti sit about 75 km apart on opposite sides of Cook Strait, which separates the North and South Islands, and D’Urville is about 500 m from the South Island while Kapiti sits 5 km from the North Island.

Historical records suggest that in October 1912, five little spotted kiwis were introduced to Kapiti Island from the South Island’s Jackson Bay as part of a conservation management program. No other little spotted kiwi have been moved to Kapiti since, but they managed to breed themselves out of a severe genetic bottleneck situation, which describes a sharp reduction in population size, into the species’ biggest population, with around 1,200 individuals today.

The islands of New Zealand, with little spotted kiwi population locations marked. Credit: K. Ramstad et al.

While the original D’Urville population went extinct by the early 1980s, the last-known female and male were moved to the predator-free sanctuary of Long Island, which is part a series of drowned valleys poking up out of the Pacific Ocean near New Zealand’s South Island, known as the Marlborough Sounds. Two males from Kapiti were also moved to Long Island, and a Kapiti female joined them in 1989. The Long island population now stands at about 50 individuals. Around the same time, groups of 12 to 40 little spotted kiwi were transported from Kapiti Island to six other predator-free island sanctuaries around New Zealand in an effort to safeguard the species. All populations have been experiencing positive population growth to this day.

Because the Long Island little spotted kiwi population was founded by individuals from both Kapiti Island and D’Urville Island, it was hoped that it harboured the most genetic diversity, and hence the most value for the future of the species. A team led by Kristina Ramstad, a geneticist from the Allan Wilson Centre for Molecular Ecology and Evolution at New Zealand’s Victoria University of Wellington, and Rogan Colbourne and Hugh Robertson from the Department of Conservation at New Zealand’s Research and Development Group, ran a genetic survey on little spotted kiwi from four populations on the Kapiti, Long, Tiritiri Matangi and Red Mercury Islands. “There were all these ideas floating around about what the genetic diversity of the little spotted kiwi would look like, but it had never been measured at all,” says Ramstad. “In the meantime, there was this concern that they probably have low diversity, and we need to find the D’Urville Island offspring and move them.”

But what they found through a genetic analysis several little spotted kiwi populations, was that the D’Urville Island male and female that were put on Long Island in the 1980s – the birds upon which all hopes of substantial genetic diversity rested – had never actually bred. They didn’t even produce one chick. Which means that all the little spotted kiwi on the planet, from every population, have come from the five birds that were originally put on Kapiti Island in 1912. And even worse for the Long Island population, the analysis revealed that nearly all of them were the direct offspring of a single mating pair.

The team found that the oldest known little spotted kiwi on Long Island, a 34-year-old male, was one of the founding three moved from Kapiti Island to Long Island in the 1980s. Because the D’Urville birds didn’t breed, this old Kapiti male and his mate are essentially the kiwi version of Adam and Eve. Ramstad estimates that around a fifth of the entire population are his second generation offspring, or grandchildren, and the rest would be his sons and daughters. It doesn’t get more inbred than that, and instead of being what was assumed to be the most genetically diverse population, with a combination of Kapiti and D’Urville birds, Long Island actually harbours the least genetically diverse population. “We don’t know why [the D'Urville birds didn't breed],” says Ramstad. “We don’t know how long little spotted kiwi live and we don’t know what’s their oldest age of reproduction. It’s still a bit of a guess, they keep outliving the scientists following them. So the birds [from D'Urville Island], could have been too old, or one of them could have been infertile. It could simply be a case that they didn’t fancy each other.”

A little spotted kiwi chick. Credit: © Andrew Digby

Ramstad was also shocked by how quickly the little spotted kiwi populations were losing genetic diversity. In the largest population of 1,200 birds on Kapiti Island, the analysis revealed that they were behaving genetically like a population of just 40 birds. Each of the populations were found to be losing genetic diversity with every generation, and were all going through the process of genetic erosion in different ways, which is a danger to their evolutionary longevity. “I think these findings were a surprise to everyone. In fact, I know they were, even the people who thought there’d be low diversity,” says Ramstad. “We were also shocked to find that a population as big as Kapiti looks like it didn’t just came from five birds, but all of the genetic diversity in that population could be explained by just three of those birds reproducing, two of them being female.”

New Zealand’s Department of Conservation is now reviewing the analysis, which was published in Proceedings of the Royal Society B today, to figure out how to ensure the future of their iconic and beloved bird. Ramstad believes that the results will likely see a change in the classification of the species to threatened or endangered. “What this study has told us is we need to be more careful. But the Department of Conservation are doing the right thing, and that is, don’t keep all your kiwi on one island, [because] what if one island is reinvaded by stoats, what if someone sets fire to one island? They’ve got the kiwis spread over multiple islands, and they are now going to be gauging if they need to take more birds from Kapiti Island and to those smaller, more recently founded populations that are now experiencing a second bottleneck to boost their genetic diversity.”

A new study is now underway to figure out how the inbreeding in little spotted kiwis is affecting their health, and Ramstad is conducting a similar genetic analysis on the critically endangered Rowi, a species that has also gone through a genetic bottleneck situation of just 180 individuals before growing to a population of around 400 today. “It’s such a privilege to be able to work with these birds. To be in a position where my research could tell anybody something new about kiwi is always exciting. It’s meant a lot to me to work on them and understand them on this level.”

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Pallas's Long-tongued Bat (Glossophaga soricina). Credit: Bernard Dupont (flickr.com/people/berniedup)

The Pallas’s long-tongued bat uses blood to change the shape of its mop-like tongue as it feeds in mid-air, researchers have discovered. High-speed video footage has revealed that an increased flow of blood to the tip of the bat’s tongue causes scores of tiny hair-like projections to become swollen and erect, allowing the bat to maximise its nectar-gathering potential with each lap.

Like the hummingbird, the Pallas’s long-tongued bat (Glossophaga soricina) from South and Central America expends a great deal of energy hovering over flowers while lapping up nectar. To sustain this activity, these small-bodied animals have to maintain the highest metabolic rates of all vertebrates, relying on the sugary substance they ingested mere minutes ago to almost exclusively fuel their hovering activity. A 2008 study in the Journal of Experimental Biology led by Kenneth Welch from the Department of Ecology, Evolution and Marine Biology at the University of California found that in Pallas’s long-tongued bats, 78% of the energy they need for hovering flight is provided by the processing of recently ingested sugar, while hummingbirds can fuel around 95% of their hovering flight in the same way. Compare this to the relatively inefficient 25 to 30% of exercise metabolism that humans and other mammals can fuel using dietary sugars, because we rely so heavily on other types of fuel such as glycogen and triglyceride, and you can see how impressive these creatures are.

Pallas's long-tongued bat feeding in mid-air. Credit: Vitor Barão (flickr.com/people/vitorbarao)

It’s impressive, but still pretty stressful business. Both hummingbirds and Pallas’s long-tongued bats are living in constant states of just-fed or starving, and they consume most of their body fat every day just to make it through. So they’ve evolved several morphological features to make them nectar-processing machines, including light, compact bodies (Pallas’s long-tongued bats weigh on average 9 grams), specialised intestines that are super effective at assimilating sugar, flight muscles made up of fast-twitch muscle fibres that can sustain high-intensity hovering flight, and their tongues are so long, they’ve had to evolve special places to keep them. The hummingbird keeps its tongue in an elongated bill, while the Pallas’s long-tongued bat has a snout-like rostrum to fold his inside. When elongated, their tongues will grow to about double their resting size.

The tip of the Pallas’s long-tongued bat’s tongue is covered in organised rows of slender filamentous papillae, or little hair-like projections that sit flat against the tongue when it’s at rest, and fan out from the tongue when it’s being used. Scientists have known about these papillae for a long time, but it was assumed that they existed to increase the surface area of the tongue and catch the odd piece of pollen or droplet of nectar in the space between them, like a simple, static brush.

Scanning electron micrograph of the tip of Glossophaga soricina’s tongue showing hair-like papillae. Credit: Cally Harper

Then in 2011,  Alejandro Rico-Guevara and Margaret Rubega from the University of Connecticut published a study in Proceedings of the National Academy of Sciences (PNAS) using high-speed cameras to watch 30 hummingbirds lap at nectar inside clear tubes (video here). Hummingbird tongues are split into two at the tip, and the space between the fork is filled with tiny, interlocking plates called lamellae. No one had suspected that these structures could be deliberately moved in any way, but by watching the hummingbirds feed in slow motion, Rico-Guevara and Rubega saw that as the tongue extends towards the nectar, its two tips separate, causing the lamellae inside to unfurl. When the hummingbird’s tongue is withdrawn, the lamellae roll back inwards, and the nectar is trapped between the tongue tips, ready to be safely delivered to the mouth. It was this discovery that led Cally Harper, Sharon Swartz and Elizabeth Brainerd from the Department of Ecology and Evolutionary Biology and School of Engineering at Brown University to try out the same technique on the nectar-eating Pallas’s long-tongued bat.

Describing their findings in today’s edition of PNAS, the team first saw that the hair-like papillae became erect during feeding, extending off the surface of the tongue with each lap just as the tongue approached maximum extension. The papillae were even manoeuvred to change their orientation so they could sit perpendicular to the tongue’s long axis, thereby maximising its nectar-catching surface area. More footage revealed that this movement occurred even when the tongue had not made contact with the sticky nectar, which proved that surface tension release did not drive the changes in the shape of the bat’s tongue. This was significant, because the hummingbird’s tongue movements are reliant on this surface tension release, so the researchers reasoned that some other mechanism – something internal – was responsible for papilla erection in Pallas’s long-tongued bats.

Blood flow and papilla erection in feeding G. soricina. The lower line tracings show the tongue in pink, the vascular sinuses and papillary veins in red, and the sugar water in light grey. Credit: Cally Harper et. al.

Based on what they observed in the vascular morphology of the Pallas’s long-tongued bat’s tongue, they suggested that rapid blood flow to the area was causing the papillae to become swollen and erect during nectar feeding. More video footage confirmed this. ”A colour high-speed movie shows increased blood flow to the vascular sinuses and engorgement of the papillary veins during nectar feeding,” they wrote, describing how the tongue was pale pink in the footage as it first extended from the mouth, which indicated the presence of relatively little blood in the vessels. Then, “As the tongue reaches maximum extension, the vascular sinuses and papillary veins engorge with blood and become bright red as the papillae become erect. Blood is temporarily trapped within these vessels and the papillae remain erect throughout tongue retraction.”

During lapping, the length of the tongue tip was also increased by more than 50%, and the researchers think that as the tongue extends from the mouth, this causes the contraction of certain muscle fibres, which not only causes it to decrease in width or diameter and increase in length, but it also compresses the arteries and veins in the tongue to displace more blood down into the tongue tip.

While this kind of mechanism has not yet been found in any other mammals, the researchers suggest that it could also be in play in the tiny, nectarivorous Australian honey possum (Tarsipes rostratus), because its tongue is equipped with enlarged blood vessels and a significant artery sitting right in the tip.

Papers cited:

Welch, K., Herrera M., L., & Suarez, R. (2008). Dietary sugar as a direct fuel for flight in the nectarivorous bat Glossophaga soricina Journal of Experimental Biology, 211 (3), 310-316 DOI: 10.1242/jeb.012252

Rico-Guevara A, & Rubega MA (2011). The hummingbird tongue is a fluid trap, not a capillary tube. Proceedings of the National Academy of Sciences of the United States of America, 108 (23), 9356-60 PMID: 21536916

Cally J. Harper, Sharon M. Swartz, and Elizabeth L. Brainerd (2013). Specialized bat tongue is a hemodynamic nectar mop
Proceedings of the National Academy of Sciences

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My book, Zombie birds, astronaut fish and other weird animals, has just been released in the US, and is available from Amazon and in bookstores.

(L) Merope tuber. Credit: Renato Machado et. al. (R) Tinkerbella nana. Credit: John T. Huber et. al.

A new species of forcepfly with enormous genital pincers has been discovered in Brazil, bringing the total number of known species in this family to three. Plus a tiny fairyfly named Tinkerbella nana has been found in Costa Rica, and at  250 μm long, it’s invisible to the naked eye, and one of the smallest insects in the world.

Affectionately described as “an inscrutable enigma to entomologists”, almost nothing is known about the biology of the nocturnal and secretive forcepfly. We’re not really sure how they live, what they eat, how they mate, and no one’s ever seen one of their larvae. Adult forcepflies are very small, ranging from 10 mm to 20 mm, and their flattened bodies allow them to live under logs, bark and leaf litter, most often near stream or river banks. Like crickets and katydids, they can stridulate by rubbing its body parts together to attract a mate or ward off potential predators.

It’s not known for sure what the function of their extraordinarily large terminal forceps is, but most researchers assume they’re used by the males to grip onto the females during copulation. It’s also been suggested that they could be used for fighting between male rivals, which has been observed their male relatives from the Panorpa genus of scorpionflies.

A close-up of the monstrous genital forceps of Merope tuber. Credit: Renato Machado et. al.

The first forcepfly species ever found was Merope tuber, discovered in eastern North America by British naturalist Edward Newman in 1838. Initially assumed to be very rare, American entomologist George W. Byers later discovered that they have quite an extensive range, from southeastern Canada to northern Georgia, west to Kansas, Minnesota, and eastern Iowa. M. tuber is the only known member of the Merope genus, most likely named after the dullest daughter of Atlas and Pleione in Greek mythology, and the wife of that guy who tricked this cat into minding his watermelon (for eternity).

Almost a century after M. tuber was discovered, another species was found, this time in the town of Yallingup in the Margaret River wine region of Western Australia. British entomologist, Frederick J. Killington, managed to collect just one individual of the species called Austromerope poultoni, and it took another 40 years for a second specimen to be found. In 1995, a fossilised, extinct species of forcepfly called Boreomerope antique was discovered in Siberia and dated to the Middle Jurassic period.

Now, a team from Texas A&M University, the National Institute of Amazonian Research and the Sao Paulo State University in Brazil, and led by entomologist Renato Machado, has discovered the third species in the Meropeidae family of forcepflies and the second species in the Austromerope genus. This pale, golden coloured species named Austromerope brasiliensis was named after its home near the Mata Atlântica forest of southeastern Brazil. It is the first forcepfly found in what’s known as the Earth’s Neotropical Zone, which covers all of South and Central American, plus the Mexican lowlands, the Caribbean islands, and southern Florida.

Merope tuber's genital forceps are longer than its abdomen. Credit: Renato Machado et. al.

The existence of a South American forcepfly was predicted in 1973 by entomologist George W. Byers from the University of Kansas, who said that it could be the family connection between the North American and Australian species. In their recent paper published in ZooKeys, Machado and his colleagues come to the same conclusion through a comparison of all four known species of forcepflies.

First they paired the extinct genus of forcepfly, Boreomerope, with the North American Merope genus together, because they have so many similar morphological features, and then they paired the Australian and new Brazilian species together in the same genus, Austromerope. From this comparison, they suggested that the forcepflies had a common ancestor living on Pangaea 200 million years ago, and with the break-up of this ancient super-continent, the Meropeidae family was split into two main branches – one in the southern hemisphere, represented by the Austromerope genus, and one in the northern hemisphere, represented by M. tuber and the extinct B. antique. Which fits, because according to fossil evidence, B. antique existed in the northern hemisphere after Pangaea had split. “The widespread distribution of Meropeidae corroborates the fact that the family arose when all continents were connected,” the team concludes.

A female Tinkerbella nana. The Scale line = 100 μm. Credit: John T. Huber et. al.

And this week, John Huber from the Canadian Department of Natural Resources and John S. Noyes from the Canadian National Collection of Insects have announced the discovery of a new species of fairyfly, which they named Tinkerbella nana, after the fairy and the dog from Peter Pan. Happily, ‘Nana’ happens to be derived from ‘nanos’, the Greek word for ‘dwarf’.

A member of the family Mymaridae, which includes the smallest known insects in the world, T. nana stretches to just under 250 μm (micrometres), which is so impossibly small, it’s just 111 μm larger than the current smallest insect in the world – a male Dicopomorpha echmepterygis Mockford, found in 1997 and stretching a mere 139 μm long.

The Tinkerbella fairyflies were collected using a super-finely knit net that was swept through rainforest vegetation at the La Selva Biological Station in the province of Heredia, Costa Rica, over two hour periods, and then dumped into ethanol to preserve the catch.

Publishing their findings in the current issue of Journal of Hymenoptera Research, the Huber and Noyes describe the species’ pale colouring, ranging from yellows and browns and white, and spectacular wings, covered in delicate, long bristles called macrochaeta. They suggest that this type of wing could help the fairyfly to reduce the levels of drag and turbulence it has to fight while in the air, which is important, seeing as they have to flap their tiny wings hundreds of times per second just to keep afloat.

While distinct in enough ways to earn itself a place in a new genus, T. nana is closely related to the world’s smallest known winged insect, Kikiki huna, which has a body length of just 155 μm. Huber and Noyes say this is probably about as small as a winged insect could possibly get, however Huber remarked, “If we have not already found them, we must surely be close to discovering the smallest insects and other arthropods.”

Papers cited:

Norman F. Johnson (1995). Variation in Male Genitalia of Merope tuber Newman (Mecoptera: Meropeidae) Journal of the Kansas Entomological Society, 68 (2), 224-233

Louis A. Somma, James C. Dunford (2007). Etymology of the earwigfly, Merope tuber Newman (Mecoptera: Meropeidae): Simply dull or just inscrutable? Insecta Mundi

Machado, R., Kawada, R., & Rafael, J. (2013). New continental record and new species of Austromerope (Mecoptera, Meropeidae) from Brazil ZooKeys, 269, 51-65 DOI: 10.3897/zookeys.269.4255

Huber, J., & Noyes, J. (2013). A new genus and species of fairyfly, Tinkerbella nana (Hymenoptera, Mymaridae), with comments on its sister genus Kikiki, and discussion on small size limits in arthropods Journal of Hymenoptera Research, 32, 17-44 DOI: 10.3897/jhr.32.4663

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Cyanogaster noctivaga. Credit: George M. T. Mattox et al

“Wait, wait, wait. What is all this?”

“WE’RE HERE TO CLAIM THE THRONE.”

“All of you? You can’t fit those horses in here. Is the King even expecting you? I wasn’t told there was a siege scheduled today. Look, see, all I’ve got in my diary is, “Organise shoes into ‘comfortable’ and ‘who made these, they make my feet bleed just by looking at them from across the room’”, and I’ve done that.”

“BUT YOU DON’T HAVE ANY FEET.”

“They’re not my shoes, obviously.”

“MOVE ASIDE, BLUEBELLY. YOUR INBRED KING HAS AN APPOINTMENT WITH OUR MULTIPLE WEAPONS.”

“Inbred ki… Oh dear. You’ve got the wrong blackwater. You need Blackwater Bay.”

“Blast. Again! WELL CAN WE TROUBLE YOU FOR SOME PORRIDGE AND A PLACE TO REST OUR CATAPULTS.”

“You could, but we don’t have any porridge.”

“BLAST!”

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A new species of miniature, transparent fish has been discovered in the highly acidic Rio Negro in Brazil, the largest blackwater river in the world. Both the males and the females have bright patches of iridescent blue on their stomachs and the base of the tail.

“As soon as we had the little ‘bluebelly’ in the net, we knew it was something quite special,” says Ralf Britz, an ichthyologist at London’s Natural History Museum. Together with George M. T. Mattox from the Universidade de São Paulo and his team, Britz discovered the nocturnal fish during an expedition to the small village of Santa Isabel do Rio Negro in the Brazilian state of Amazonas. They named it Cyanogaster noctivaga, which means “bluebelly night wanderer”.

The Neotropical zone that encompasses southern Mexico, Central and South America, and the West Indies is home to more freshwater fishes than anywhere else on Earth, and also has the richest collection of ‘miniature fishes’. In 1988, Stanley Weitzman and Richard Vari from the Smithsonian National Museum of Natural History determined that all species under 26mm long should be classified as miniature. The smallest of all the miniature fish in the world is Paedocypris progenetica, the females stretching up to just 10.3 mm and the males 9.8 mm. The smallest mature specimen ever found was only 7.9 mm long, so smaller than the width of your fingernail.

P. progenetica was discovered by Maurice Kottelat from the Raffles Museum of Biodiversity Research in Singapore and colleagues in the blackwater peat swamp forests of Southeast Asia, and described in a 2006 edition of Proceedings of the Royal Society B. Until recently, the low-nutrient, highly acidic peat swamp forests were regarded as a species poor ecosystem, with low faunal diversity and few endemics. However, almost half of all known Asian miniature fish species have been discovered in peat swamps, their tiny bodies allowing them to thrive even when the water levels sink dangerously low. Even in dry periods, the peat acts as a wall to keep in clean and cold water, so tiny fish can survive droughts in shallow swamp pools; the burrows of other animals; or even in the soil, which permanently retains enough water to sustain only the most diminutive of animals.

Rock plateau beach in the Rio Negro, where Cyanogaster noctivaga was found. Credit: George M. T. Mattox et al

At no more than 17.4 mm long, the recently discovered bluebelly night wanderer, C. noctivaga, appears to be thriving in the slow moving blackwater of the Rio Negro. Eleven specimens were scooped up at around 1.5 m depth, and described in a recent edition of Ichthyological Exploration of Freshwaters. “Of course we were surprised to find this really unusual fish in an area of the Amazon that can be considered one of the best known,” says Britz, suggesting that the nocturnal species lives in much deeper water during the day, but comes up to the surface at night, possibly for food.

Because it was night time, and the water of the Rio Negro is the colour of a cup of black tea, spotting the transparent bluebelly was tricky, and the team had to look for flashes of blue in their nets to know if they’d caught any. And because the fish would turn a milky pink as soon as they died, which was moments after they were plucked from their murky home, getting a photo of their incredible colouring was no simple task. ”The photo of the live fish was one of the trickiest photos I have ever taken, because Cyanogaster is extremely fragile and died within seconds after having been transferred to the photo tank,” says Britz, adding that he didn’t manage to get a single decent image on the first night.

A dead and preserved Cyanogaster noctivaga, its colouring faded. Credit: George M. T. Mattox et al

“The second night I put the photo tank next to the waterline on the shore and the camera and flash next to it,” he said. “Then George and I seined, and once we had some of the little beauties in the net, I transferred them with a big spoon to the phototank, so they never had to be out of water. That did the trick, and they survived for a few minutes, enough to get a few decent shots, one of which is the one in the paper. So the full colouration and beauty of the fish was only revealed after we looked at the photos. And then we were almost speechless.”

Once the team had photos of the live specimens, they could zoom in to get a better look at the anatomy, and at that point they were pretty certain that they’d found not only a new species, but a new genus. “This initial gut feeling was then confirmed by our detailed studies later in the labs in Sao Paulo and London,” says Britz.

Apart from the large eyes and unique colouring, C. noctivaga was distinguished from its closest relatives due to the number and arrangement of their teeth and fin rays. It belongs to the Characiformes order of ray-finned bony fishes, and this group often has specialised teeth with several cusps, or projections, on the crown. Called multicuspids, these complex teeth are also usually arranged in several rows in the jaw, and looking at their arrangement can be a key identifier for new species. “Cyanogaster is quite unusual in having only four multicuspid teeth in the inner row and just a single unicuspid (a conical tooth with one cusp) tooth in the upper jaw,” says Britz. “Most other characiforms, if they have multicuspid teeth, have more than four in the inner and more than just one in the outer row.”

Britz says that because the Rio Negro is such a vast, undisturbed river, there is no indication that the bluebelly nightwanderer is in any kind of trouble at this point. It’s hoped that further research will reveal more about how this new genus of tiny fish fits within its larger family group.

And speaking of tiny fish, here’s a great comparison of a Paedocypris and its humungous cousin, the critically endangered giant barb, Catlocarpio siamensis. Plus a man who is really mad that his fish is so big.

Extremes in body size of species of the Order Cypriniformes. (A and B) Adult Paedocypris progenetica Credit: Dr. Kobayashi. (C) Adult Catlocarpio siamensis, one of the largest species of Cypriniformes (172 cm, 102 kg) Credit: Dr. Zeb Hogan

Papers cited:

Stanley H. Weitzman and Richard P. Vari (1988). Miniaturization in South American freshwater fishes; an overview and discussion Proceedings of the Biological Society of Washington, 101 (2), 444-465

Kottelat, M., Britz, R., Hui, T., & Witte, K. (2006). Paedocypris, a new genus of Southeast Asian cyprinid fish with a remarkable sexual dimorphism, comprises the world’s smallest vertebrate Proceedings of the Royal Society B: Biological Sciences, 273 (1589), 895-899 DOI: 10.1098/rspb.2005.3419

Mayden, R., & Chen, W. (2010). The world’s smallest vertebrate species of the genus Paedocypris: A new family of freshwater fishes and the sister group to the world’s most diverse clade of freshwater fishes (Teleostei: Cypriniformes) Molecular Phylogenetics and Evolution, 57 (1), 152-175 DOI: 10.1016/j.ympev.2010.04.008

George M. T. Mattox, Ralf Britz, Mônica Toledo-Piza, & and Manoela M. F. Marinho (2013). Cyanogaster noctivaga, a remarkable new genus and species of miniature fish from the Rio Negro, Amazon basin (Ostariophysi: Characidae) Ichthyol. Explor. Freshwaters, 23 (4), 297-318

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My book, Zombie birds, astronaut fish and other weird animals, has been released in the US through Adams Media this week, and is available from Amazon.

Microcaecilia dermatophaga. Credit: Wilkinson, Sherratt, et. al.

A new species of skin-feeding amphibian has been discovered in French Guiana. Named Microcaecilia dermatophaga, it joins just three other caecilian species whose young have been observed to regularly feed on their mother’s skin.

Amphibians can be pretty good parents, committing themselves to various guarding, transporting and feeding behaviours to foster their offspring. The Surinam toad from French Guiana has her fertilised eggs implanted into her skin by the male as a protective measure, while the gastric brooding frog of Queensland, Australia, swallows her eggs so her tadpoles can develop in her stomach. Another type of amphibian, the legless, wormlike caecilian, has evolved a unique, and apparently quite effective, parenting technique that has only recently been observed.

Caecilians are found in Central and South America, Subsaharan Africa, India, South-east Asia and the Seychelles. They live mostly in tropical soils but a few aquatic and semi-aquatic species can be found in freshwater systems around the world. They can grow to almost 1.5 m in length and breed through internal copulation, which can last between 45 minutes and three hours. Unlike any other type of amphibian, male caecilians mate using a phallic organ that folds out from inside its cloaca.

The caecilian order (Gymnophiona) can be classified into three different groups depending on how their young develop: there are those whose eggs hatch in the water, where the young will live until they have metamorphised into their final, adult form, just like frogs; there are those whose young hatch from eggs and develop into the adult form without having to metamorphose, known as direct-developing; and there are those that retain their eggs internally and give birth to live young, known as viviparity. Because almost all species of caecilian spend their lives in underground burrows, their natural behaviour can be very difficult to study – they have to be disturbed before they can be observed.

An oviparous, or egg-laying caecilian, M. dermatophaga. Credit: Wilkinson, Sherratt, et. al.

In the 1990s, Mark Wilkinson from the Department of Zoology at the London Natural History Museum and Ron Nussbaum from the University of Michigan discovered unique baby teeth in hatchlings of the South American direct-developing caecilian, Siphonops annulatus. Together with observations that the young remained with their mother until they had grown a great deal and that mothers tending to a brood had different, much paler skin than adult females without dependant young, the team suggested that the S. annulatus young could be feeding on the mother’s skin secretions, sort of like mammalian lactation, using specialised teeth.

They were almost right, because 16 years later, Alexander Kupfer from the London Museum of Natural History and Wilkinson watched as the young of an East African species called Boulengerula taitanus fed on their mother’s skin, which was the first ever observation of this behaviour, known as maternal dermatophagy. “Rather than scraping up skin secretions, the young of B. taitanus use their teeth to peel and eat the specially modified skin of their mothers,” they reported in Nature.

Two years later, Kupfer and Wilkinson also confirmed the behaviour in S. annulatus, and described it all of its grossness in Biology Letters:

Feeding behaviour is quite frenetic with the young frequently tearing pieces of skin by spinning along their long axes and sometimes struggling over the same piece of skin. The mother remains calm during this activity. When the mother has been peeled, the young continue to search for and eat fragments of skin on the substrate. Feeding bouts are short: just seven minutes for the only complete bout observed and interspersed with long periods of quiescence. Skin feeding was seen twice in one family group separated by approximately 64 hours.

They concluded that while the behaviour had only been observed in a handful of caecilians from two species, there was reason to believe that skin-feeding was a widespread phenomenon in the Siphonopidae family of direct-developing caecilians. “Biogeographic considerations, the separation of Africa and South American land masses, and inferred timescales of amphibian diversification all suggest that skin-feeding is an ancient form of parental care in caecilians, which has probably persisted in multiple lineages for more than 100Myr [million years].”

The team also discovered that young S. annulatus individuals would congregate around their mother’s cloacal opening to drink the clear fluid that would flow from within.

Tropical forest of French Guiana where M. dermatophaga is found. Credit: Wilkinson, Sherratt, et. al.

Now, Wilkinson and Emma Sherratt from the London Natural History Museum have discovered a new species of direct-devloping, skin-feeding caecilian, M. dermatophaga - the first new caecilian species to be discovered in French Guiana in more than 150 years. “The forest was very full of mosquitos, making for uncomfortable digging – that is how we find caecilians, using a bladed hoe to turn over rotten logs and dig in the soil,” says Sherratt. “I was systematically breaking down a rotten log, when I came across this pink wiggling animal, about 15cm long. I grabbed at it and instantly screamed with delight – A CAECILIAN! We found several more that day, breaking through mounds of rather orange, clay like soil. We found juveniles and adults. Subsequent trips by my colleagues a few years later have found even more.”

Publishing last month in PLoS One, the team describes M. dermatophaga as a new species due to the number and type of rings that run around its segmented body. They maintained live individuals in captivity with an artificial night and day cycle and a ‘nest’ constructed from compressed soil covered with clear plastic. A piece of wood was placed over the top, and removed at ’daytime’ and ‘nighttime’ intervals so the caecilians could be observed with as little disturbance as possible. After about a month of incubation, the eggs hatched, and their mother curled around them. The body length and mass of both parent and offspring were recorded periodically as the skin-feeding behaviour was observed.

“The altricial hatchlings (newly-hatched young that are relatively immobile, unable to burrow) peel off, remove and ingest the outer layer skin of the mother, which she [the mother] is shedding. The skin is very fatty, and she is not hurt in the process, although her body weight decreases over the time because she herself is presumably not feeding,” says Sherratt. “The mother’s skin changes when the eggs hatch, it becomes quite pale, a bit like when snakes are close to shedding their skin. The young of these species have distinctive multicasted teeth – good for scraping – that are shed when the young start their independent existence. The feeding happens periodically over one month, although we don’t know just how frequently each day.”

The teeth of M. dermatophaga. Credit: Wilkinson, Sherratt, et. al.

According to Sherratt, the skin-feeding behaviour occurs in quick, 30-second bursts. During the month after hatching, the young caecilians grow in mass considerably so they are strong enough to burrow, so it looks their skin-feeding behaviour is giving them a good start in life.

Because the behaviour has been found in two of M. dermatophaga’s distant relatives, from two different families, the team suggests that this could mean that it evolved independently in the ancestors of each of these families, or it could support Wilkinson and Kupfer’s earlier suggestion that skin-feeding is a widespread behaviour in direct-developing caecilians. Variations on the theme could also be common in the other types of caecilians – offspring of the viviparous Scolecomorphidae family are known to feed on the lining of their mother’s uterus before birth. Further observations in other caecilian species are needed to better understand the origin of this behaviour.

“My gut feeling is this is a widespread trait in direct-developing caecilians (more than half of the known species), but I’m not speaking for my colleagues, this is my opinion,” says Sherratt. “We need to continue studying the reproductive biology of caecilians – there are so many species for which we just don’t know anything about their biology. It is a very exciting time of discovery! If this is so, this trait evolved at least 100 million years ago and has obviously been beneficial for caecilians.”

Here’s footage David Attenborough filmed with some of the team the first caecilian skin-feeding behaviour was reported:

Sources cited:

Wilkinson, M., & Nussbaum, R. (1998). Caecilian viviparity and amniote origins Journal of Natural History, 32 (9), 1403-1409 DOI: 10.1080/00222939800770701

Kupfer, A., Müller, H., Antoniazzi, M., Jared, C., Greven, H., Nussbaum, R., & Wilkinson, M. (2006). Parental investment by skin feeding in a caecilian amphibian Nature, 440 (7086), 926-929 DOI: 10.1038/nature04403

Wilkinson, M., Kupfer, A., Marques-Porto, R., Jeffkins, H., Antoniazzi, M., & Jared, C. (2008). One hundred million years of skin feeding? Extended parental care in a Neotropical caecilian (Amphibia: Gymnophiona) Biology Letters, 4 (4), 358-361 DOI: 10.1098/rsbl.2008.0217

Wilkinson, M., Sherratt, E., Starace, F., & Gower, D. (2013). A New Species of Skin-Feeding Caecilian and the First Report of Reproductive Mode in Microcaecilia (Amphibia: Gymnophiona: Siphonopidae) PLoS ONE, 8 (3) DOI: 10.1371/journal.pone.0057756

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My book, Zombie tits, astronaut fish and other weird animals, will be released in the US on 18 April 2013, and is available for pre-order from Amazon.

Credit: Genevieve Anderson

The gooey ink secretions of sea hares do more than just repel or distract their predators; scientists have discovered that this sticky substance can also mask their senses of smell and taste.

Sea hares (genus Aplysia) are large, herbivorous mollusks that are closely related to sea slugs and nudibranchs. The largest sea hare, Aplysia vaccaria, can grow up to 75 cm long and 2 kg in weight. Sea hares have a great sense of smell thanks to a pair of large sensory rhinophores that sit erect on their heads like bunny ears. Their colouring, ranging from light grey, green and red to dark purple with white spots, helps them to camouflage, as it is determined by the colour of the seaweed they eat and live nearby.

Because they don’t have a protective shell, sea hares have equipped with a whole bunch of defence mechanisms to keep predators away from their soft flesh, which contains toxins as a last resort. They have two defensive glands in their mantle cavity; the ink gland sits on the roof of the cavity above the gill and produces a purple ink, and the opaline gland, which is located on the floor of the cavity under the gill, produces a milky white, viscous secretion called opaline. If a sea hare is threatened or attacked, a siphon inside its mantle cavity will pump one or both of these secretions out into the surrounding water. Research has shown that these secretions can act as a decoy in response to predators such as sea anemones, crustaceans and fish, leading them to misdirect their attacks. It also commonly works as a repellent, prompting tentacle shrivelling in predatory sea anemones.

Because it is so well defended, the sea hare doesn’t have a lot of predators to worry about, but California spiny lobsters, (Panulirus interruptus) are known to take their chances on them occasionally. So in 2005, Charles Derby and Cynthia Kicklighter from the Neuroscience Institute and Department of Biology at Georgia State University in the US decided to use the spiny lobster to test the effects of the sea hare’s ink secretions. They found that the high levels of amino acids in the ink secretion mimicked the stimulatory properties of food, so when the lobsters came in contact with the secretion, they would leave the sea hare alone and try to eat the ink instead. The spiny lobsters would start “digging with the legs into the substrate covered by the secretion (“digging”) and moving the first two pairs of legs to the mouth (“grabbing”), behaviours similar to that produced when spiny lobsters are chemically stimulated to search for and sample food items”, the team reported in a 2005 issue of Current Biology (PDF). This form of chemical defence, which has a similar result to a lizard discarding its tail to distract a predator, is known as ‘phagomimicry’.  The team concluded that, ”The detection of high concentrations of free amino acids typically signals to spiny lobsters the presence of food. Sea hares exploit this property of their predator’s nervous system by releasing secretions that mimic stimulatory properties of food and thereby divert the attention of the attacker. The highly viscous nature of opaline may create a tactile sensation of food, contributing to the mimicry.”

During this experiment, Derby and colleagues noticed that the spiny lobsters would also habitually groom their antennules (small antennae that act as the ‘nose’) and mouthparts when they came into contact with the opaline secretion, which suggested that it could be hindering their ability to taste and smell. So more recently, Derby joined Tiffany Love-Chezem and Juan Aggio from Georgia State to test if it was the chemical composition or the stickiness of the opaline secretion that was achieving this effect.

Still from video of spiny lobster attacking a sea hare. Credit: Charles Derby et. al.

First they extracted the water-soluble fraction of the opaline, which leaves behind the amino acids and other chemical attractants but keeps the stickiness, and painted it onto the tips of the spiny lobsters’ antennules. The lobsters were then offered delicious smelling ‘shrimp juice’ and the researchers measured the electrical activity in both their chemosensory (odour detection) and motor neurons. Reporting in Experimental Biology this week, the researchers reveal that unlike the control lobsters that had clean antennules and hence no problem sniffing out the shrimp juice, the lobsters with opaline solution on their antennules failed to get excited by food right in front of them, their chemosensory and motor neurons have been significantly reduced.

But when the researchers applied a solution of amino acids found in opaline to see if its chemical composition affected the neuronal activity of the lobsters, they found that the lobsters reacted normally to the shrimp juice. This means that the thick, sticky texture of the opaline is the key to physically blocking the ability of the sea hare’s predator to identify it as food. “Our experiments provide strong support that the sensory inactivation is principally due to the secretion physically covering the antennule and thus blocking chemicals from accessing chemosensory neurons,” the researchers conclude. “Our experiments do not provide evidence for the chemical properties of opaline, either excitatory or suppressive, contributing to the inactivating effect, but experimental design issues allow that there might be some chemical effect that we could not resolve.”

The researchers compare this newly discovered mechanism with a defensive behaviour found in some species of moths, whose ultrasonic emissions can ‘jam’ the echolocation of predatory bats, thereby masking the moth’s whereabouts. However, the say that this is the first time that an organism has been proven to inactivate the senses of its predators through a chemical mechanism.

Watch the video:

Papers cited:

Kicklighter, C., & Derby, C. (2006). Multiple components in ink of the sea hare Aplysia californica are aversive to the sea anemone Anthopleura sola Journal of Experimental Marine Biology and Ecology, 334 (2), 256-268 DOI: 10.1016/j.jembe.2006.02.002

Kicklighter, C., Shabani, S., Johnson, P., & Derby, C. (2005). Sea Hares Use Novel Antipredatory Chemical Defenses Current Biology, 15 (6), 549-554 DOI: 10.1016/j.cub.2005.01.057

Love-Chezem, T., Aggio, J., & Derby, C. (2013). Defense through sensory inactivation: sea hare ink reduces sensory and motor responses of spiny lobsters to food odors Journal of Experimental Biology, 216 (8), 1364-1372 DOI: 10.1242/jeb.081828

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My book, Zombie tits, astronaut fish and other weird animals, will be released in the US next month, and is available for pre-order from Amazon now.

Caught on camera for the first time, this image shows the newly identified Marohita mouse lemur. Credit: Peter Kappeler

Genetic analysis has revealed the existence of two new species of Madagascan mouse lemur, bringing the total number of recognised species to 20.

Weighing less than 100 g and rarely stretching more than 28 cm, tail included, mouse lemurs are the smallest primate in the world. Native to the forests of Madagascar, these strictly nocturnal omnivores come in either grey or a rich, rusty brown, and each one has a distinctive white splash running between the eyes and down the snout. Eighteen new mouse lemur species have been discovered since 1993, and their genus, Microcebus, boasts one of the highest species numbers of all primate groups. But because mouse lemur species all look so similar, distinguishing them can now only be done through genetic analysis.

During a field trip in December 2003, Rodin Rasoloarison from the University of Antananarivo in Madagascar caught two female mouse lemurs and one male in the Forêt de Marohita of the Toamasina province in eastern Madagascar. Four years later, in the Anosy region of south-eastern Madagascar, Rasoloarison caught six individuals in the Forêt de Manantantely and four more in the Forêt d’Ivorona. He performed a morphological analysis on the individuals, including weighing and measuring various external and internal parts, and fur colours were identified using colour charts. Tissue samples were then extracted and sent to Anne Yoder and Dave Weisrock at Duke University in Durham, North Carolina, for analysis.

Two mitochondrial and four nuclear loci were sequenced from the two new species, and then analysed alongside 279 mitochondrial and 209 nuclear sequences from different mouse lemur species found in 78 sites across Madagascar. The team used a technique called a Bayesian phylogenetic analysis for both the mitochondrial and nuclear loci, and a STRUCTURE analysis to infer the presence of distinct populations using multi-locus nuclear genotype data.

“I would say that in general, it is highly unusual to describe new species of primates in this age of global travel and consequent access to remote areas of the planet,” says Yoder, a Professor of Biology and Evolutionary Anthropology and Director of the Duke Lemur Centre. “That said, the number of described lemur species has more than tripled in the last 10 years. A large number of these new species have been mouse lemurs.

“I suspect that there are even more mouse lemur species out there to be found (indeed, there are hints of that in some of our genetic data).  Mouse lemurs are morphologically cryptic, they are tiny, they are nocturnal, and they occur in remote places. It therefore makes a lot of sense that the harder we look, the more species we will find.”

A captive Microcebus murinus mouse lemur, which occurs in the same area as the newly discovered Anosy mouse lemur. M. murinus considered an alternative model system to mice and rats in biomedical research on human disease and aging. Credit: David Haring of the Duke Lemur Center.

The team named the new species from the Forêt de Marohita (Marohita meaning “many views”) the Marohita mouse lemur (Microcebus marohita). It turned out to be a very large species, stretching 275–286 mm from nose to tail, with a considerable body mass of up to 89 g. “The large body mass of M. marohita is remarkable,” the team report in today’s issue of the International Journal of Primatology. “The single male M. marohita, which we judge to be a subadult, is as heavy as M. gerpi males, which until the new species described here, were the largest known mouse lemur males.” The females were found to be 20% heavier than all other known females.

The colouring of the Marohita mouse lemur’s long, dense fur ranges from a gorgeous ginger to a dusty umber with a coat of blackish grey underfur. Its undersides and the upper surfaces of its paws are a whitish beige and it has long, pink little fingers.

The second new species, found in the Anosy region in 2007, was called the Anosy mouse lemur (Microcebus tanosi). It has a total body length of 275 mm and weighs 49 g, which still makes it relatively large by mouse lemur standards. Like the Marohita mouse lemur, the Anosy mouse lemur has a rusty-coloured coat, but has a slightly darker colouring on its undersides.

Due to continuous habitat destruction threatening the survival of the Marohita mouse lemur, the researchers have classified it as endangered. “As revealed by a recent visit (in 2012), the forest of Marohita is highly degraded and has been substantially damaged since the initial collecting trip from 2003,” they report. “Thus, despite its species’ name, this mouse lemur is threatened by ongoing habitat destruction, and “many views” of its members are unlikely.”

The Tanosi mouse lemur’s status is so far unknown, but the researchers say it will likely also been classified as endangered due to similar environmental concerns. “The forest at Manantantely was already heavily degraded at the time of our field survey, whereas the forest at Ivorona was only slightly degraded, but the current state of these forests and the mouse lemur populations therein is not known,” they report.

“Public awareness in Madagascar is very important,” adds Yoder. “I have found that the Malagasy people take great pride in their lemurs, as soon as they understand that Madagascar is unique in having lemurs, and also, that certain lemurs are specific only to a particular area.  Also, and obviously, the government needs to participate in protecting the forests, and in providing economic alternatives to slash and burn agriculture to the Malagasy people.”

Here’s a video of mouse lemurs at the Duke Lemur Centre. Their eyes are so big, blinking looks like an enormous effort for them:

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Credit: VA Institute of Marine Science (VIMS)

There’s nothing like the thought of a delicious piece of meat with human teeth wrapped in prison stripes to put you to a gentle, dreamless sleep.

Despite the way it looks, the sheepshead fish (Archosargus probatocephalus) has at least one thing going for it. While other members of the Sparidae family are trying out various forms of hermaphroditism, including changing from female to male (protogyny), doing the opposite (protandry), or being unisexual (gonochorists), the sheepshead is just sitting at home watching cartoons and leaving its genitals where they are. So that’s something.

Sheepshead incisors. Credit: Glen J. Kuban

Another good thing about this huge creep is that, unlike one of its relatives, the Salema porgy (Sarpa salpa), you won’t risk having a terrible trip when you eat one.  Apparently they taste great! The Salema porgy, also of the Sparidae family and nicknamed the dreamfish, was reportedly used for recreational hallucinogenic purposes in the Mediterranean during the Roman Empire and has played a role in traditional Polynesian ceremonies. Along with a handful of other fish, the flesh of the Salema porgy can sometimes inflict ichthyosarcotoxism on those who eat it, which is a very rare form of poisoning caused by the toxins of a tiny species of marine plankton called Gambierdiscus toxicus. This poisoning from contaminated fish flesh prompts intense hallucinations and terrifying nightmares that can last for several days.

As reported by Luc de Haro and Philip Pommier from the Centre Antipoison of the Hôpital Salvator in Marseille, France, in a 2006 issue of Clinical Toxicology, a 90-year-old man ate a Salema porgy in Saint Tropez in 2002 and two hours later was hallucinating and having nightmares about people and birds screaming, which lasted a further two nights. He literally thought he was losing his mind. “Fearing that these symptoms might signal the beginning of a major mental illness, he did not tell his friends or attending physician. The manifestations abated three days after he had eaten the fish,” de Haro and Pommier report.

Prior to that, a 40-year-old man also fell victim to ichthyosarcotoxism while holidaying in the French Riviera and had hallucinations of screaming animals and giant, menacing spiders surrounding his car.  In 2009, a fisherman named Andy Giles caught one in the English Channel, which is unusual because they usually keep to warm waters of the Mediterranean and African west coast, and told the Daily Telegraph, “Now I realise what it was and the effects it can have, perhaps I should have taken it into town to sell to some clubbers!” Andy lol.

So the sheepshead fish doesn’t do any of that stuff. But it does have human teeth. Sheepshead fish are a common North American marine species that span from Cape Cod and Massachusetts through to Florida and the Gulf of Mexico to Brazil. Preferring coastal habitats around rock pilings, jetties, mangroves, reefs and piers, they can grow up to around 91 cm in length and weigh up to 9.6 kg. They have five to seven distinctive black, vertical bars running down their silvery bodies, which is why the sheepshead is also called the convict fish. And true to their name, sheepshead fish are notorious for stealing bait and somehow being in cahoots with the Joker.

Look at these criminals. Credit: mentalblock_DMD; Flickr

A fully-grown adult sheepshead will have well-defined incisors sitting at the front of the jaw, and molars set in three rows in the upper jaw and two rows in the lower jaw. It has strong, heavy grinders set in the rear of the jaw too, which are particularly important for crushing the shells of its prey. As with humans, this unique combination of teeth helps the sheepshead process a wide-ranging, omnivorous diet consisting of a variety of vertebrates, invertebrates and some plant material.

Credit: Texas Parks and Wildlife Department

When they’re young, sheepshead fish will eat marine worms, bryozoan ‘moss animals’ and pretty much anything soft-bodied they can catch in the seagrasses. Although thick, sharp teeth begin to appear when a sheepshead is just 4.5 mm long, it will have to wait until it’s about 15 mm long before all the incisors have come in and the back teeth begin to develop into adult molars. Once they reach around 50 mm in length, the sheepshead will advance to eating more robust, armoured prey such as echinoderms, barnacles, clams, crabs and oysters, using their highly specialised teeth.

During this stage, its jaw musculature is also developing, and this keeps improving right through to old age. So an old fish living around a good supply of hard-shelled prey will end up having much greater jaw crushing power than a younger fish in a less rich environment. “Evidence strongly suggested that oral jaw crushing force was an important determinant of diet in these fishes,” said L. P. Hernandez from the Museum of Comparative Zoology at Harvard University and P. J. Motta from the Department of Biology at the University of South Florida in a 1997 issue of the Journal of Zoology. Hernandez and Motta had been observing the oral crushing performance of sheepshead fish from birth through to adulthood. “There was a significant correlation between increased force production and increased durophagous [shell-crushing] habit. Studies such as this one speak directly to the relationship between maximum functional potential and actual patterns of resource use.”

It’s not clear why the sheepshead is called the sheepshead, but it’s been suggested that it refers to how its teeth look like sheep’s teeth. A quick Google and cursory glance over some disgusting farm teeth, and I don’t really see the comparison, but another suggestion is that the name relates to their silhouette. And there’s something to be said for a sheepshead fish that has managed to keep its silhouette looking as non-offensive as it does, because look what happened to the Asian sheepshead of the Labridae family.

Here’s a video of some very American men with a live sheepshead:

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The new species of nudibranch from the Phyllidiella genus. Credit: Terry Gosliner

There’s a new species convention happening somewhere right now and none of us got the memo because old. But that’s okay because we’ve got ROFLCon and Anthrocon Playstations.

This week an international team of researchers announced that they’ve identified some 80 new species of plants and animals along Papua New Guinea’s Hindenburg Wall, a 50-km long, 300 m high limestone cliff face running through the Star Mountains region of the Western Province. Included in the haul is a native rat the size of a Chihuahua, frogs, butterflies and the littlest wallaby.

Papua New Guinea is also responsible for over 30 underwater delegates on their way to SpeciesCon from Madang Lagoon, which is a large, incredibly rich area skirted by tiny islands and coral reefs, and arguably the most diverse reef on Earth. A team of researchers led by James Thomas from Nova Southeastern University’s Oceanographic Center in Florida and hosted by a team of scientists from the Paris Museum of Natural History have identified new species of nudibranchs, feather stars (or crinoids) and shrimp-like amphipods after a three-week survey of the 15 km x 4 km lagoon.

A section Papua New Guinea's Madang Lagoon. Credit: Goldsztajn; Wikimedia

“The work was quite taxing for the group,” says Thomas. “We drove in trucks to boats and then to our dive sites. Upon completing our dives/collections, we returned to a large lab complex established and hosted by the a French expedition team on site and sorted our materials and took photographs and prepared specimens for museum collections and DNA analysis.”

Thomas’s team had originally carried out a survey of the lagoon more than two decades years ago, and found that the same species plus more now inhabited the warm, calm environment. “We wanted to see how the diversity had changed in the intervening 25 years. What we found was that it is still thriving despite encroaching human-related impacts,” he says.

Judging by the variety of nudibranchs, feather stars and amphipods, which can act as model organisms or ‘indicator species’ for an ecosystem’s level of diversity, this lagoon is richer in species than the entire Great Barrier Reef. Speaking with Australia’s ABC Radio last week,

“Finding new species on reefs is not unusual,” he says. “We did find a lot of unique and interesting species. I was especially excited to find one of my species living within the mantle of a clam. Few reports of this are known.”

This new, unnamed amphipod belongs to the genus Leucothoe, members of which are often found living in the interior canals of sponges and sea squirts. Less often, these little crustaceans make their way inside the shells of bivalve mollusks such as clams, and Thomas’s clam-dwelling amphipod had even set up its home with a mate. Sometimes these amphipods will live inside a host in communities of over 100 individuals.

J. Emmett Duffy from the Viriginia Institute of Marine Science was the first to document eusocial behavior, which describes a kind of complex social organisation, in marine sponge-inhabiting snapping shrimp, in 1996 and again in 2003. Thomas has documented eusociality, communal living, and “nest guarding” in tropical leucothoid species. Prior to this, scientists had assumed eusocial behaviour,  was restricted to insects and naked mole rats. “The inner canals of sponges provide a protective breeding habitat for amphipods, where adults provide extended parental care of juveniles until they reach sexual maturity,” Thomas reported in a 2007 issue of Zootaxa (PDF download).

The new species of amphipod from the Leucothoe genus living inside the mantle of a clam. A male and female pair were found. Credit: James Thomas

James’s team also found a new distinctive species of nudibranch. The charismatic sea slug looks like a marshmallow coated in pink chocolate and popping candy, with two little rhinophores, which are the pair of sensory antennae that sit on the head area and do most of its smelling and tasting. And now’s a good time to mention that a certain relative (of the nudibranch!) has a detachable penis and two back-ups coiled up inside its body for the Ultimate College Experience.

The new species of Amphipod (genus Leucothoe). Credit: Nova Southeastern University

For all its diversity, the Madang Lagoon environment is threatened by land-based pollution runoffs from nearby mines and a new tuna canneries scheduled to open, and Thomas says that while there are some efforts by NGO’s in the region that are mainly terrestrial, many conservation organisations are yet to really commit in a larger capacity in the marine systems. “The cultural and political realities in the area make it very difficult to make substantial progress,” he says. “Since conservation organisations cannot generate a lot of fundraising for this little-known site, most of them have bypassed it for more lucrative areas for financial fundraising.”

The team will begin analysis and description of species and plan to share their findings with the local Madang villagers and regional and federal governments in the hope that conservation efforts in the region are ramped up.

Correction: A picture of a feather star was originally posted here and labelled as a new species discovered by Thomas’s team in the Madang Lagoon. It was included in the series of images provided to me, so I assumed that it was one of the new species found. This species is Oxycomanthus bennetti and was actually discovered by Johannes Müller in 1841 and photographed by Greg Rouse from the Scripps Institution of Oceanography.

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My book, Zombie tits, astronaut fish and other weird animals, will be released in the US next month, and is available for pre-order from Amazon now.

Artist conception of Helicoprion by Ray Troll. Credit: Ray Troll

After a century of colourful guesses, CT scans have revealed what’s really going on inside the nightmarish jaw of Helicoprion, a large, 270 million-year-old cartilaginous fish with an elaborate whorl of teeth set in the middle of its mouth.

In 1899, Russian geologist, Alexander Petrovich Karpinsky, gave this six-metre-long fish the name Helicoprion, meaning “spiral saw”, based on a fragmentary fossil found in Kazakhstan. Because the saw he was describing had been separated from the rest of the body, Karpinsky couldn’t be sure where it would have fit, so initially he suggested that it started in the fish’s mouth, and curled upwards along the snout as an external coiled mass of fused-together teeth. Think a sawfish’s saw, only curled upwards. Further guesses were made during the early 1900s by a number of researchers from around the world, including American palaeontologist Charles Rochester Eastman. Eastman had issues with the idea that such an unwieldy apparatus could have possibly sat inside this poor creature’s face. Publishing in a 1900 edition of The American palaeontologist, Eastman favoured the idea that the whorl protruded from somewhere along the length of the fish’s back, acting as some sort of defensive display, perhaps.

The many faces of Helicoprion. Reconstructions of Helicoprion since 1899. Earliest models (a – d) posited the whorl as an external defensive structure, but feeding reconstructions dominate more recent hypotheses. Artwork © Ray Troll 2013.

A few years later, Karpkinsky followed Eastman’s train of though, and suggested that the Helicoprion’s whorl could have formed part of the animal’s tail, or perhaps extended from its dorsal fin, or sat lower down on its back. In 1907, American ichthyologist, Oliver Perry Hay, found a fossilised specimen that was still sitting in its natural position, and judging from this, favoured the jaw theory. But did it sit in the upper or lower jaw? And did it sit in both? Such questions were impossible to answer with the few and fragmentary specimens these researchers had to work with.

Regardless, the general consensus in the earliest hypothetical reconstructions of Helicoprion was that this terrible, toothy whorl surely served a defensive purpose. Later this century, this perception has changed, and researchers moved towards the idea that the whorl was used mainly for feeding, and therefore was associated with the creature’s jaw.

A recent reconstruction of Helicroprion with the tooth whorl sitting inside the mouth like a tongue. Credit: Mary Parrish, Robert Purdy, Victor Springer and Matt Carrano from the Smithsonian National Museum of Natural History

In 1950, a crucial Helicoprion whorl specimen was discovered by Danish palaeontologist Svend Erik Bendix-Almgreen in the Waterloo Mine near Montpelier, Idaho. Named IMNH 37899 and housed in the Idaho Museum of Natural History, it was first described by Bendix-Almgreen in 1966. It might have been seriously crushed and disarticulated, but along with the 117 discernible serrated tooth crowns sitting on a spiral with a diameter of 23 cm was some very telling cranial cartilage. This proved for the first time that at least some of the whorl was contained inside Helicoprion’s mouth.

But that didn’t limit the possibilities. Over the past fifty years, researchers have suggested that the whorl extended awkwardly from the lower lip, curling underneath the chin; sat inside the mouth where the tongue should be; or perhaps sat further down towards the throat.

Leif Tapanila with two of the largest Helicoprion whorls in the world. Credit: Ray Troll

Now a team led by Leif Tapanila from the Department of Geosciences at Idaho State University, and curator of the Idaho Museum of Natural History, have gained unprecedented insight into the structure of Helicoprion’s skull. IMNH 37899 was scanned using an ACTIS scanner at the University of Texas High-Resolution X-ray CT Facility, and from this, a scaled, 3-D computer-generated model of the animal’s skull was generated.

“Our reconstruction posits that the tooth whorl is a singular, symphyseal [fused] structure of the lower jaw that occupied the full length of the mandibular arch,” the team reported in Biology Letters yesterday. This means that instead of extending past the lower jaw and coiling underneath the chin, as had been previously suggested, the whorl grew inside the lower jaw. This way, just as sharks have multiple rows of teeth that are continuously replaced, Helicoprion had a partly concealed tooth factory that began near the area where the upper and lower jaws meet, ran over the mouth wear the tongue would be if it had one, and then into the cartilage supported by the lower jaw (see first image).

“Continual growth of the whorl pushes the tooth–root complex in a curved direction towards the front of the jaw, where it eventually spirals to form the base of the newest root material, and this process continues to form successive revolutions,” the researchers say. “At some time, prior to a complete 360 degree evolution of spiral growth, tooth crowns are concealed within tessellated cartilage on the upper jaw.”

As Helicoprion didn’t have any teeth on his upper jaw, the team suggests that the predatory fish would have broken down its soft-bodied prey, such as cephalopods and small fish, by repeatedly slicing them with a single row of serrated teeth. When it closed its closed its lower jaw, the whorl of teeth were pushed backwards, “providing an effective slicing mechanism for the blade-like serrated teeth and forcing food to the back of the oral cavity”.

Tapanila and colleagues suggest that the Helicoprion’s jaw could have extended past 50 cm long, and some tooth whorls would have boasted some 150 teeth. The team also says that the creature is not a shark, as others have assumed, but a chimaera (Holocephalan), which is a group of cartilaginous fish also known as ratfish or ghost sharks that branched off from the sharks 400 million years ago. “It was always assumed that the Helicoprion was a shark, but it is more closely related to ratfish, a Holocephalan,” says Tapanila. “The main thing it has in common with sharks is the structure of its teeth, everything else is Holocephalan.”

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Even though many breeds look very different from each other, dogs can still recognise other dogs' faces, and categorise them separately from non-dog species. Credit: spilltojill; Flickr

They may have the largest physical variety among all animal species on Earth, but dogs can still recognise one of their own over any other animal based on simple images of their faces.

Since their domestication somewhere between 15,000 and 100,000 years ago, dogs have been learning to use facial cues as an important part of their social communication. When interacting with us, dogs can read and use our facial expressions to gauge where our attention lies and sometimes what we’re feeling. Studies have also shown that they’re better than wolves and some primates at understanding the hints we give them about an object’s whereabouts – particularly if it’s a treat – by reading our eyes and head movements. Dogs also display a range of facial expressions themselves, which researchers believe are used for communicating with other dogs, whether it’s to impart hostility, friendliness, fear, and so on.

Along with the ability to make and read facial expressions, another important part of being a social animal is recognising the face of your fellow species member, or conspecific, even when the other senses are masked. A number of studies have demonstrated the ability of certain animals to recognise their conspecifics based exclusively on visual cues, including Rhesus macaques, sheep, cows, and some birds and invertebrates.

Dogs also fall into this category, which is pretty impressive, considering the huge variety of breed combinations and morphological differences within this species. Breeds range in size from the biggest 100-kg Mastiffs to the smallest 1-kg Chihuahuas. Tails can be straight or curly, as can their coats, which can come in many colours, lengths and hair types. Ears can be floppy or pointy. Eyes can be obscured by fur or excess skin and mouths can be droopy or taut. There are now 400-500 recognised dog breeds around the world, and because dogs breed quickly, there’s no sign that this morphological variety will slow down any time soon.

Autier-Dérian's dog subjects. The subject’s name, breed (Bc border collie, L labrador) or cross-breed (Cb), sex and age are specified below. Credit: Dominique Autier-Dérian / Animal Cognition

Knowing that dogs can identify a picture of another dog, two independent teams of researchers, one led by Anais Racca from he Department of Biological Sciences at the University of Lincoln in 2010 and the other by Sanni Somppi from the Faculty of Veterinary Medicine at the University of Helsinki in 2012, tested if dogs could recognise pictures of other dogs when also faced with pictures of humans and inanimate objects. While both confirmed that this was the case, the teams restricted their experiments to 24 pictures per category, and this, says Dominique Autier-Dérian from LEEC and National Veterinary School in Lyon, France, in a new Animal Cognition paper, is not enough. “Because of the small number of stimuli used, these studies could not take into account morphological species-specific diversity. In fact, there is more morphological diversity among breeds in domestic species compared to wild species.”

So Autier-Dérian and his team put together a more comprehensive experiment to test whether dogs can recognise each other as a separate group, away from other animals, despite their incredible physical diversity. Nine dogs were selected (see profiles above) and routinely exposed to a large variety of dog, human and other non-dog species’ faces, with the aim of better understanding how well they know their own kind.

Examples of stimuli used. a) Dog heads displaying the variety of dog breeds b) Other "non-dog species’’. Credit: Dominique Autier-Dérian / Animal Cognition

The nine dogs were exposed to a pool of 3,000 pictures of different breeds, both pure and mixed, on one of two computer screens. On the other screen, a selection of 3,000 faces from 40 wild and domestic “non-dog species” including cows, cats, rabbits, birds, reptiles, wild felines and humans appeared*. The computer each would appear on was randomised, and the faces were scaled to take up 70% of the canvas for uniformity. They could be front-on, side-on, or turned slightly towards the viewer. Each dog ended up viewing more than 144 pairs of pictures randomly selected from the two pools, and never saw the same picture twice.

More images showing a variety of head positions. Credit: Dominique Autier-Dérian / Animal Cognition

The dogs were trained to wait in a windowless “sitting area” where it would view the two computer screens. When two images appeared on the screens, the dog would be told “image!” from an instructor behind, prompting it to move towards one of the screens and place its paw on a tablet in front of it. The instructor would then say ‘‘place!/here!’, and the ’dog would retake its original sitting position to await the next pair of images. If the dog choose the face of another dog, it would receive a treat, indicating that the instructor wanted it to choose a dog’s face every time. If the dog made an incorrect choice, it would return to its sitting area empty-handed.

b) The dog sits in front of the instructor, between two computer screens. c) When hearing an order from the instructor, the dog expressed his choice by going to a given screen. Credit: Dominique Autier-Dérian / Animal Cognition

The researchers found that despite the huge diversity of dog breeds and non-dog species shown to these nine dogs, each one managed to successfully recognise which faces belonged to dogs and which faces didn’t. Whether it was the face of a big, shaggy dog or a tiny, sleek one, the dogs managed over a number of different trials to lump them all into the same category, away from any of the other species.

“The fact that dogs are able to recognise their own species visually and that they have great olfactory discriminative capacities insures that social behavior and mating between highly morphologically different breeds is still potentially possible and therefore that, although humans have stretched Canis familiaris to its morphological limits, its biological entity has been preserved,” the researchers concluded.

What’s left to do now is to figure out what physical characteristics the dogs were using to distinguish the pictured dogs from the other species.

*The researchers note that this time, no faces of wolves or foxes were included.

*****

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The new species on Lombok - the Rinjani scops owl (Otus jolandae). Credit: Philippe Verbelen

A new species of owl called the Rinjani scops owl has been discovered, and it’s unique to the tiny Indonesian island of Lombok.

Until fairly recently, it was common practice for scientists to identify owl species based largely on their plumage and morphology. Both features are important in distinguishing all kinds of birds, but can be unreliable, as owls often change their colouring to better blend in with their environment. The same species of spocs owl living in different geographic regions can have noticeably different plumage colours and patterns, which had led to what Smithsonian ornithologist Joe T Marshall referred to in 1978 as “several embarrassing misalignments”.

Marshall had been sent to Thailand in the late ‘70s to fix up some messy taxonomy of its endemic owls, and it was here that he became the first researcher to propose that vocalisations were a more reliable identifier of scops owl species than variations in morphology and plumage. Using this new technique,  he went on to completely revise the classification of the scops owl genus Otus.

A 1964 illustration of the sandy scops owl (Otus icterorhynchus) from Allen Phillips and Joe Marshall's 'The Birds of Arizona'. According to Marshall, the absence of wings emphasises the important parts of the plumage for species comparisons. Credit: Joe T Marshall

Since then, recordings of owl vocalisations have become a big part of identifying owl species, and this is how George Sangster from the Department of Vertebrate Zoology at the Swedish Museum of Natural History and Ben King from the Ornithology Department at the American Museum of Natural History discovered the Rinjani scops owl of Lombok, and named it after Indonesia’s second highest volcano, Gunung Rinjani.

Lombok is located in the West Nusa Tenggara province of Indonesia, about 25 km from Bali to the west and 15 km from Sumbawa to the east. It has an area of 4,725 km² and a population of 3.16 million, and its famous Gunung Rinjani National Park is home to porcupines, long-tailed macaques, civets and the endangered Javan rusa deer.

A pure coincidence saw both Sangster and King travel to Lombok in 2003 to record and study the vocalisations of a local population of nightjars to identify whether they belonged to a potentially new species that occurs on the neighbouring islands of Flores and Sumba, or to the large-tailed nightjar species (Caprimulgus macrurus) with which it had long been associated. It turns out this was a population of large-tailed nightjars, but while they were there, Sangster and King picked up on some owl vocalisations they had never heard before.

“On the very first night, just a few hours after my wife and I arrived on Lombok, we heard the vocalisations of an owl that we were not familiar with,” says Sangster. “Initially we weren’t sure whether it was perhaps a previously known species from Java and Bali that for some reason had been overlooked on Lombok. That was quickly ruled out when we played it back our sound recordings of the owl. The owls responded strongly to this and approached us so we could get a nice view. They looked nothing like the owls on Java and Bali.”

“I arrived on Lombok three days after George for the purpose of getting tape recordings of the same species of nightjar George wanted to record and for the same reason,” says King. “At the time, George and I had not met and did not know each other, although we knew of one another. My experience was similar to George’s. While I was recording the nightjar, I heard a song that sounded like an owl, but unlike any I’d heard in years of fieldwork in Indonesia. I recorded the owl and played the tape back to the owl and eventually I got a good view of a pair.”

Rinjani scops owl. Credit: Phillipe Verbelen

There are 51 known species of scops owls, making their genus the largest in the ‘true owls’ family Strigidae. Scops owls are characterised by their small, erect ear tufts, relatively compact bodies and plumage the colour of dusty bark and dried-out leaves. The other family of owls is the Tytonidae family of barn owls, with ears hidden on the side of their heads and placed asymmetrically for an enhanced detection of sound position and distance when they’re hunting, and a more distinct facial mask. They could also quite possibly be some kind of witch.

The Moluccan scops owl (Otus magicus), which stands around 24 cm tall, is common species on the Indonesian islands, and was thought to occur in various parts of Lombok. It looks so similar to the new Rinjani scops owl that over the last 100 years, no one had bothered to confirm this via vocalisation recordings or DNA comparisons. “Prior to my Lombok visit, I had not thought of tape-recording the scops owl there, as it looked like the Moluccan scops owl, and I just assumed that the earlier researchers were correct in their assessment,” says King.

“However,” adds Sangster, “its whistle sounded completely different from the Raven-like croak of [the Moluccan scops owl]. Now things got interesting: we might have a different species. However, we fully expected that some taxonomist already had given a name to this population, and we did not realise at the time we had discovered an entirely new species. That came later, at home when we checked the taxonomic literature and examined our recordings more closely.”

Map of Wallacea, a group of Indonesian islands separated by deep water straits from the Asian and Australian continental shelves, showing approximate rages of owl species and subspecies. Credit: Sangster, King et. al.

Over the past decade, Sangster and King have been putting together a case for their Lombok spocs owl, which they have called Otus jolandae after Sangster’s wife, as being a unique species. This involved collecting recordings from different parts of the island, investigating whether or not the owl was located on other Indonesian islands, and comparing the Rinjani scops owl to all other relevant species in museums. Finally, a DNA analysis of the Rinjani scops owl and those other species provided the confirmation the researchers needed.

“Only when we had tied up all loose ends were we comfortable announcing our new species,” says Sangster. “Owl vocalisations can be highly informative for taxonomists. They most likely have a genetic basis, are relatively easy to study, and are being used by the birds themselves to distinguish species. However … one needs to respect the same scientific principles that apply to other types of data. You must have multiple recordings, study geographic variation, perform statistical analyses, and make sure that the right comparisons are made (to avoid the ‘apples-and-oranges’ problem). In addition, most owls have very simple vocalisations, and there is no reason to expect that all species have completely unique songs. Therefore, it is always a good idea to study other types of data as well, including DNA.”

Sangster and King have published their discovery in today’s issue of PLoS One. “Although it took us almost 10 years to describe the new owl, this is hardly exceptional,” says Sangster. “Of course, all the easy ones have been described a long time ago, so those bird species that remain undiscovered will not easily give up their true identity.”

What isn’t clear just yet is how this owl has remained Lombok’s only endemic species, when the island of Sumbawa is just 15 km away – an easy distance for an owl to fly. Sangster has a theory that because the smaller islands in the Indonesian archipelago only harbour one species of scops owl each, some kind of competitive exclusion could be at play. “This is speculative,” he adds, “and in fact more fieldwork is necessary to know for sure that the Rinjani scops owl does not occur in extreme western Sumbawa.”

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The head of a 26.7 mm remora, or sharksucker, with its strange suction disc. Credit: Dave Johnson

“The lazy remora’s inhaling lips | Hung on the keel, retard the struggling ships” – Erasmus Darwin, 1830

Remoras, or sharksuckers, are a family of eight species of tropical fish that for more than a millennium have inspired a mythology that is almost stranger than those odd little hats they’ve got on. And now scientists have figured out where the sharksucker’s sucking discs actually came from.

Remoras use their sucking discs to latch onto pretty much anything for a free ride, whether it’s other fish, turtles, divers or ships, and so they were named accordingly – in Latin, remora means “delay”, while the scientific family name Echeneidae comes from Echeneis, which is made up of two Greek words, echein (“to hold”) and naus (“a ship”). Once the meaning ‘‘holding onto ships’’ shifted to “holding back ships’’ over time, a myth was born that was so influential, it lived in the consciousness of nearly every sailor on nearly every sea voyage in the Mediterranean and Mid-Atlantic Oceans up until a few hundred years ago.

Remoras stuck to a nurse shark in the Bahamas. The suction is not seen to hurt either party. Credit: Duncan Wright, Wikimedia

The myth of ship-holding sharksuckers can be traced as far back as 350 BC, when Aristotle wrote a 10-volume encyclopaedia called History of Animals, in which he very briefly mentions, “a tiny [fish], which some call the Echeneis, or ‘ship-holder’”. While Aristotle describes the remora as being somewhat of a good-luck charm – “…which is by some people used as a charm to bring luck in affairs of law and love” – by the first century AD, it had become more than a nuisance for sailors, and for one historian, an omen that even the most powerful men in the world would do well to heed.

Six ship-holders holding a ship. From the first Strassburg edition of the Hortus Sanitatis, 1497. Credit: E. W. Gudger

In 77–79 AD, Pliny published his enormous Naturalis Historia encyclopedia, one of the largest single texts we have left from the Roman Empire. In it, he describes the phenomenon of the ‘ship-holder’ – an eel-sized fish with a suction disc that could bring warships to a halt despite the force of violent seas, whirlwinds, and storms. And not just any warships: Pliny blamed remoras for the defeat of Mark Antony at the Battle of Actium in 31 BC and hints that they were indirectly responsible for the assassination of Gaius Caligula.

Upon returning to Rome from Gaul in 41 AD, Pliny says, Caligula’s ship stopped dead, while the rest of his fleet breezed past unfettered. Unable to make any progress despite the best efforts of his four hundred rowers, Caligula sent his men down to discover the cause:

“They found this fish sticking to the rudder and showed it to Gaius, who was furious that it had been such a thing that was keeping him back and vetoing the obedience to himself of four hundred rowers. It was agreed that what astonished him in particular was how the fish had stopped him by sticking to the outside, yet when inside the ship it had not the same power. Those who saw the fish then or afterwards say that it is like a large slug.”

This was, Pliny opined, a wonderful example of “Nature surpassing herself”.

“Bales may blow and storms may rage; this fish rules their fury, restrains their mighty strength, and brings vessels to a stop, a thing no cables can do, nor yet anchors of unmanageable weight that have been cast. It cheeks their attacks and tames the madness of the Universe with no toil of its own, not by resistance, or in any way except by adhesion. This little creature suffices in the face of all these forces to prevent vessels from moving. But armoured fleets bear aloft on their decks a rampart of towers, so that fighting may like place even at sea as from the walls of a fortress. How futile a creature is man, seeing that those rams, armed for striking with bronze and iron, can be checked and held fast by a little fish six inches long!”

The remora removed, Pliny goes on to say, Caligula was free to return home, but the little fish proved ominous, because the Emperor was soon met by the murderous blades of his own men. If only he’d gotten home sooner, perhaps?

The myth of the ship-holder survived for centuries after Pliny’s death, the first English version printed in a 1494/1495 edition of an encyclopaedia by French scholar Batholomeus Anglicus. According to American historian, E. W. Gudger, who wrote a paper in Isis in 1930, the remora’s ship-holding power was believed by fishermen of the Adriatic Sea up until around 1778. He’s collected a handful of visual representations, which were particularly popular during the Renaissance period of the 15th and 16th Century.

The remora, having laid hold of the rudder of this ship, slows its progress even though its three large sails are distended by the gale. Camerarius, 1654. Credit: E. W. Gudger

Even more recently, when their boats began to slow inexplicably, some fishermen weren’t above pointing the finger at an unwitting remora or two. “They sure will hold a boat. I have seen ten or twelve under a boat at one time,” a fisherman from Key West in Florida told Gudger in the late 1920s. “My brother and me had boats just like each other in size and build but his was a little better sailor than mine. The first day he beat me, sailing before the wind, but the second day I beat him. He said, ‘No wonder I am losing, too many suckers hanging on her bottom’. All Key West fishermen know that suckers will sure hold a boat.”

Even if in reality, the remora’s suction force is no where near enough to anchor even the smallest of boats, its suction disc is no less remarkable to its admirers now than it was thousands of years ago. So in December last year, ichthyologists Ralf Britz from the Department of Zoology at the Natural History Museum in London and David Johnson from the Division of Fishes at the National Museum of Natural History in Washington published a paper in the December 2012 issue of the Journal of Morphology explaining just how the remora got its suction disc.

The remora's suction disc, with its numerous lamellae. Credit: PacificKlaus at Flickr

The remora’s suction disc is a ribbed and elongated structure that sits on the fish’s flattened head, a varying number of thin plate-like pieces of skin called lamellae (like on the sticky toes of geckos) flanking either side of a central vane. The disc is supported by a complex series of muscles and bones that create suction by erecting and depressing the lamellae. Once attached, the remora can slide backwards to increase the pressure of the suction, or forwards to release its grip. The oval suction disc extends from just past the nostrils to beyond the pectoral fins, which are the first fins as you run your eyes along the fish head to tail.

Since the early days of comparative vertebrate anatomy in the 1820s and 1830s, scientists have hypothesised that the remora’s sucking disc was a highly modified dorsal fin – the fin that sits on the top of a fish’s body (think: shark fin). But more recently, over the last ten years or so, scientists have been disputing this. So Britz and Johnson injected red dye into the bones of larval remora and other fish from the Morone genus, which includes variations of bass and white perch, so they could watch them grow, and took snapshots as they developed through their juvenile and adult stages. This way, the researchers could see if at any point these bones behaved differently to produce a sucking disc in one fish, and a perfectly formed dorsal fin in the other.

A remora with its bones stained red so the early development of the dorsal fin (A, above) is visible. Below is a close-up of the developing dorsal fin. At this stage, the remora's development is about the same as that of other fish, but later it will change to form the suction disc. Credit: Ralf Britz

Up to a certain point in the fishes’ development, the dorsal fin and supporting skeleton appeared to be developing in very much the same way in both fishes. Then, gradually over time, a series of small changes saw the dorsal fin bones expand and shift forwards towards the remora’s head, and by the time the juvenile remora had grown to 30 mm long, it had a 2 mm-long, perfectly formed sucking disc. What Britz and Johnson also found was that this suction disc was made up of all the same components as the Morone fish’s dorsal fin, including the tiny, delicate fin spines, spine base and supporting bones, but the remora’s spine base, which now acts as the base of the disc, had greatly expanded.

“The sucking disc of the sharksuckers of the family Echeneidae is one of the most remarkable and most highly modified skeletal structures among vertebrates,” the researchers wrote, having solved a problem of which Gudger had said in 1926, ‘There is no embryological problem in all the realm of ichthyology today which is so unique and offers so much of interest as the mode of formation of the sucking disc in any form belonging to the family Echeneididae [sic].’’

And oh yes, you can get your remora Pokémon and Yu-Gi-Oh cards here and here.

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Skeletal anatomy of the first freshwater mosasaur, Pannoniasaurus inexpectatus, found in Hungary. Credit: Makadi L, Caldwell MW, Osi A (2012)

Fossilised bones of a new species of mosasaur have been unearthed in Hungary, providing the first evidence that these giant, aquatic lizards lived in both freshwater and marine environments.

Since the first mosasaur was discovered in 1764, thousands of specimens have been discovered all over the world. But because there was no evidence that they lived in freshwater environments, it’s been assumed that they were exclusively marine predators.

In 1999, a single vertebra was discovered alongside a variety of fish and crocodile teeth in the waste dump of a coal mine in Ajka, an industrial town in Western Hungary. This is the first known specimen of the mosasaur – named Pannoniasaurus inexpectatus, because no one expected to find one in what used to be a freshwater environment. The following year, a dried-up river system known as the Csehbánya Formation was exposed by a site named Iharkút, discovered about 20 km away at an open-pit bauxite mine. Over several years, more fragmentary vertebrae of Pannoniasaurus were found at the site, as well as the bones of turtles, lizards, amphibians, alligators, pterosaurs and more fish. But these fossils were so fragmentary, they were mistaken for the bones of large terrestrial lizards.

It wasn’t until recently that more bones, including the all-important skull bones, were discovered at Iharkút, causing the excavators to realise that they had unwittingly been piecing together a new, very unusual species of ancient aquatic reptile.

“Until now, mosasauroids have been regarded as an exclusively marine group. However, with the discovery and description of Pannoniasaurus, mosasauroid evolution is now understood as also having involved important and unsuspected adaptations to freshwater ecosystems,” the team, led by palaeontologist Laszlo Makadi from the Hungarian Natural History Museum, report in today’s issue of PLoS One. The researchers have now collected over 100 Pannoniasaurus bones, from individuals large and small, young and old, from the Csehbánya Formation, and the site has never produced a single marine or brackish faunal or floral specimen.

Discovered in August 2010, the mosasaur Platecarpus was a marine lizard, like most other mosasaurs so far discovered. Credit: Illustration by Stephanie Abramowciz, NHM Dinosaur Institute

According to the researchers, Pannoniasaurus lived between 85.8–83.5 million years ago during the Late Cretaceous period, and it thrived in a freshwater river system of an island landmass in the western Tethyan Archipelago – a series of island chains that sat between the African and Eurasian landmasses in what once was the Tethys Ocean.

Comparing  its vertebrae and other bones to those of known marine mososaurs, the team suggested that Pannoniasaurus could have grown up to six metres long, making it the largest known aquatic predator of this palaeonenvironment. It appears to have been super-specialised for its freshwater environment, with a flattened skull like a crocodile for ambushing prey on both land and in shallow water, and while there is little evidence for what its limbs would have looked like, the researchers suggest that it could have had limbs like a terrestrial lizard. They say Pannoniasaurus probably adapted to its environment like modern freshwater river dolphins adapted to life in the Amazon, Ganges, Yangtze and La Plata River.

The smallest vertebra found likely belonged to a Pannoniasaurus that was just 70 cm long, which, according to the researchers, means it’s likely that this area, and Ajka nearby, was a place were many individuals of varying sizes and ages lived all year round, rather than migrating from marine environments for seasonal food or breeding activity.  But they concede that definitive evidence is lacking. “Whether or not Pannoniasaurus was restricted to freshwater environments, or perhaps instead was a seasonal, opportunistic migrant and consumer in these habitats, remains uncertain,” they write in their report. “[However,] sedimentological, taphonomical (fossilising conditions), morphological and geochemical evidences suggest the former.”

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Hellbender Credit: Christian Sperka

Together with its cousins, the Japanese and Chinese Giant Salamanders, the hellbender is one of the largest amphibians in the world, and part of the only group of animals that can breathe mostly through folds of excess skin between their front and back legs. They’re a strange creature worth investing in, especially now that their numbers are declining to the point where certain populations are dying out altogether, so researchers have developed new assisted reproductive technologies to help keep these slimy salamanders around.

Hellbenders are endemic to North America and are split into two subspecies, the eastern hellbender (Cryptobranchus alleganiensis alleganiensis), which is found throughout the eastern states, and the Ozark hellbender (C. a. bishopi), which is restricted to the Ozark Mountains of northern Arkansas and southern Missouri. Both males and females grow to around the same size, stretching 24 – 40cm (9.4 – 16in) and weighing in at a rather hefty 1.5 – 2.5kg (3.3 – 5.5 lb). While many sources will tell you that we don’t really know where their common name ‘hellbender’ came from, its first use can be found in the 1812 book, A memoir concerning an animal of the class of reptilia, or amphibia, which is known, in the United-States, by the names of Alligator and Hell-bender, by American naturalist Benjamin Smith Barton. And let’s just say he was a man of his time…

“I must not omit to mention a very singular name by which this animal is known in some parts of the United States. By the negroes in the western parts of Virginia, on the waters of Holsten where it is common, the reptile is often called Hell-Bender, by reason of its slow, twisted motions when moving in the waters, which the slaves compare to the torturous pangs of the damned in hell. It is beneath the dignity of natural history to notice such vulgar names, when they serve to throw any light upon the habits or economy of an animal? And does not the moralist perceive, that there is something melancholy and distressing in the condition and reflections of those who impose such names?”

Barton, who was the first to describe the species, decided that the Native American name for the creature, ‘Tweeg’, was more fitting, but despite his best efforts, it did not stick nearly as effectively as hellbender has. Other nicknames it has acquired along the way are devil dog, ground puppy and snot otter.

An Ozark hellbender, a subspecies found in the rivers of the Ozark Plateau in Missouri and Arkansas. Credit: USFWS; Jill Utrup

Over the past couple of decades, the eastern hellbender has been experiencing drastic declines throughout its range, and researchers aren’t quite sure why. It could be the degradation of water sources that feed into their streams, new diseases or new pollutants being introduced to their streams, or a combination of all three, and its causing what’s known as a lack of recruitment, which means young hellbenders are not growing up in declining populations, leaving fewer and older individuals for breeding each year. Plus dams and polluted rivers have already relegated them to the few healthy streams that are left, which has resulted in many isolated populations that could develop genetic defects because of inevitable inbreeding.

“Our hellbenders (Ozark and eastern), and the Japanese and Chinese Giant Salamanders are the only three species in the family Cryptobranchidae … and this family contains the largest amphibians in the world. All three species are imperiled and may disappear unless conservation programs are developed for them,” says Dale McGinnity, the ectotherm curator at the Nashville Zoo, and part of the team that has recently launched the first captive breeding program for eastern hellbenders.

Hellbenders are a difficult species to breed in captivity, and getting a hold on wild individuals to bring back to the lab is no walk in the park either. “Catching hellbenders is tough work because they live under large stones in rivers and streams,” says McGinnity. “We have to get several big guys with log peaveys (a log-moving tool) to tilt the rocks up, so that one of us can snorkel underneath to see if hellbenders are present.” However, determining if hellbenders are still present in given stream will be easier in the future.

Funding from a collaborative SWG grant (State Wildlife Grant) through the Tennessee Wildlife Resources Agency supported statewide surveys, disease testing, gene banking and genetic analysis for Tennessee hellbenders. The grant also funded the development of a new technique called eDNA (environmental DNA) for determining if hellbenders are still present in a stream from minute amounts of DNA taken from a 1 litre sample of stream water. The grant funded McGinnity’s work at the Zoo and in the field Brian Miller from Middle Tennessee State University, who has done the most research on hellbenders in Tennessee over the last 25 years documenting declining populations, and Michael Freake from Lee University in Tennessee who did the eDNA and genetic work.

It’s taken a team at St Louis Zoo in Missouri many years to be the first to successfully breed Ozark hellbenders in captivity, which they did last year for the first time, by keeping them in large artificial stream systems. “The natural breeding at St Louis is great, and will produce many animals for release in the future, but the genetic variability of these offspring is somewhat limited,” says McGinnity.

Working instead with the eastern hellbender subspecies, McGinnity’s team at Nashville Zoo are developing new reproductive technologies to breed them in a laboratory setting, which, when perfected, will hopefully produce large numbers of genetically diverse offspring for reintroduction into the wild.

Hellbender egg with live embryo. Females can lay around 300 eggs at a time. Credit: Pete&NoeWoods on Flickr

The Nashville Zoo’s project launched about five years ago, with three male hellbenders and one female from a healthy wild population. It became an international collaboration, including Australian cryobiologist Robert Browne from the Zoological Society of Antwerp, who is an expert in amphibian reproductive technologies, and together they came up with painless techniques for collecting and cryopreserving sperm from captive and wild hellbenders to build up a large, cryopreserved gene bank.

Over the past couple of years, the team has also been using a new hormone injection called Amphiplex – recently developed for assisted reproduction in frogs – to stimulate egg and milt (seminal fluid) production in the captive hellbenders. “At the Zoo, we had been doing a long-term ultrasound study on the reproductive organs of our hellbenders over the seasons. By using ultrasound to determine the exact right time to inject the Amphiplex, based on the development of the testes and follicles, we have been able to reliably collect both eggs from the female and strip milt from all the males over the last two years,” says McGinnity. “We then place the sperm on the eggs and test different variables to see which might work.” Last month they announced that they were finally able to produce two healthy hellbender babies using freshly collected sperm.

One of the young hellbenders bred by Nashville Zoo. Credit: Amiee Stubbs

“We need to further develop fertilisation protocols and early egg incubation techniques to produce large numbers of offspring, but we feel confident that we will be able to do this in the near future,” says McGinnity. “We are not fully there yet, but our hopes for the project will be to produce genetically appropriate stock for reintroduction, and slow down the loss of genetic diversity in declining populations through gene banking.”

Head to Zooborns.com for more stories about new animal breeding programs, and you can hear more about the project here:

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Photo of wild New Guinea singing dog, cropped to focus on dog. Copyright: Tom Hewitt

This is one of the only photographs ever taken of a wild New Guinea singing dog, an exceptionally shy and rare animal from the highlands of New Guinea. The photograph was taken in August this year by Tom Hewitt, Director of Adventure Alternative Borneo, during a trek in the remote Star Mountains of Western New Guinea.

The second largest island on Earth containing at least 8% of the world’s known terrestrial and aquatic species, New Guinea is divided into the independent Papua New Guinea and the Indonesian-controlled West Papua. The island’s native dogs are almost impossible to find in the wild, and several recent expeditions to find individuals for captive breeding have turned up nothing, including one in the mid-90s where the team spent an entire month searching in the Eastern province highlands of Papua New Guinea. And according to Hewitt, who has been working in South-east Asia for the past ten years, the native dogs now prefer West Papua anyway, which makes locating them even harder because it is less populated, and the Singers are hidden from the locals in its vast, thickly forested areas.

The only other photograph we have of a wild New Guinea singing dog (Canis dingo hallstromi) was taken by Australian mammalogist and palaeontologist Tim Flannery in 1989 and published in his book The Mammals Of New Guinea. This, and Hewitt’s recent shot, are crucial evidence that wild populations remain in existence.

Earlier this year, Hewitt was on a private expedition with a client who wanted to climb the second highest freestanding mountain between the Himalayas and the Andes – Gunung Mandala, the highest peak of New Guinea’s Star Mountains range. At approximately 4,750m high in a little-explored region of West Papua, this is not an easy task, and according to Hewitt, it’s been ten years since a successful climb to the peak has been confirmed. Plus just making it to the Star Mountains region, where wild New Guinea singing dogs live, is a significant challenge on its own.

“To understand why it is so rarely explored, you need to know the strange variables that have collided for this part of the world and made it so remote,” says Hewitt. “It is in the middle of the second biggest island in the world that has little or no road networks, and the island itself is very isolated, as it has been forever from even the most intrepid of explorers. A trek in Papua is really a dive into the unknown and without a reliable guide, all sorts of problems can arise. Fortunately I have a guide [whom] I have worked with before on a number of occasions.”

Original photograph showing New Guinea singing dog in the distance. Copyright: Tom Hewitt

The trek to wild Singer territory begins either with a ten-day hike to the starting point village in West Papua, or a $5,500 U.S. return charter airflight. Then to get to the Star Mountains, you have to spend another ten days trekking over a 3,800m pass, which involves endless up and downs on narrow hunting trails with steep drop-offs while negotiating countless slippery logs. “West Papua … has a reputation for being dangerous and expensive – the former is not true but the latter is, but either way there are many other places in the region to visit that are more popular and accessible,” says Hewitt.

Considered one of the wettest places on Earth, the thick, mossy cloud forests and extensive swamps that make up this region are permanently damp and cold. Singers – so-called because of their unique vocalisations that are like “a wolf howl with overtones of whale song” – live mostly in these cloud forests or higher up, at elevations between 1.3km and 3km. The only other wild Canis species, including wolves, jackals and coyotes, that lives naturally at such a high altitude is the critically endangered Ethiopian wolf.

On their return trek, Hewitt and his group camped for four days within a gaping valley with 4km-high limestone peaks. Inside were many native animals and birds, including possums, tree kangaroos and cuscus, plus ancient cycad species and highland flowers and grasses. “The client and I had gone around some big boulders in the valley on the ‘trail’ and the guide and cook had stopped, which was unusual for them. The guide exclaimed ‘dog’ and he had to repeat it three times and point before we understood,” recalls Hewitt. “[the dog] was not scared, but seemed [as] genuinely curious [of us] as we were of it, and it certainly felt like a rare meeting for both sides. The guides and cook were also surprised.”

At the time, Hewitt had no idea what he was photographing, nor how special it was. When he got home, he contacted Tom Wendt, founder of New Guinea Singing Dog International (NGSDI) to let him know about the sighting. “I have had several folks contact me … in the past claiming to have seen or photographed a Papua New Guinea highland wild dog, but in every prior instance there was either no photograph to support the claim, or the photos taken were of a hybridised New Guinea singing dog at lower elevations,” says Wendt. “The only place a pure New Guinea singing dog could possibly be found would be in the remote highlands where the natives rarely visit, and due to the lack of humans present, a domestic dog would not thrive. This is exactly where Tom and his team were when the dog was sighted and photographed.”

Captive New Guinea singing dog 'singing'. Credit: whatadqr on Flickr

The average male Singer measures around 42 cm (17 inches) at the shoulder and they weigh around 11kg (25 pounds), and the females are slightly smaller. They have a very similar look to the Australian dingo (Canis lupus dingo), but are about one-third smaller, with shorter legs, broader skulls and high check bones. Janice Koler-Matznick from the New Guinea Singing Dog Conservation Society in the U.S., one of the world’s foremost experts on the animal, describes the dog’s unusual flexibility in an in-press book excerpt: “One of the first things people notice about Singers is their physical grace and agility. They have very elastic joints and spine, and therefore move fluidly: more like a cat than a dog. They are adapted to being climbers and jumpers, not long distance trotters or runners.”

Singers have short, double coats coloured either golden red or black and tan, and they have white markings under the chin, paws and the tip of the tail, and sometimes on their face, chest and neck.

According to Hewitt and Wendt, the West Papuan locals rarely see wild Singers, and have not attempted to domesticate them, especially since these canny dogs go out of their way to avoid human contact. “If a New Guinea singing dog were to travel out of the mountains to civilisation, there is a much better chance it would be killed and eaten than become a native’s hunting dog,” says Wendt.

Little is known about the origin of the Singer, but it’s thought that, like their closest relative, the Australian dingo, they were transported by people travelling between islands more than 4,000 years ago. A theory by Susan Bulmer, a New Zealand-based archaeozoologist who has worked extensively in New Guinea, suggests that an ancestral dog could have arrived in New Guinea as early as 10-20,000 years ago, when all kinds of animals were being brought back to the island. Once the land bridge connecting Australia and New Guinea had been flooded over, the two populations became distinct breeds – the Australian and New Guinea dingoes.

A captive New Guinea singing dog, looking very similar to the Australian dingo. Credit: San Diego Shooter on Flickr

Genetic studies have placed the New Guinea singing dogs into a group of dogs with ancient origins, including the basenji, Afghan hound, Samoyed, saluki, Canaan dog, dingo, chow chow, Chinese Shar Pei, Akita, Alaskan malamute, Siberian husky and American Eskimo dog. It was first described in 1957 by Australian mammalogist and zoologist Ellis Le Geyt Troughton, based on a pair at Sydney’s Taronga Zoo. This pair, from the Southern Highlands District of Papua New Guinea, was the first to be transported out of the country, and Troughton classified the dog as a new species, Canis hallstromi.

Captive New Guinea singing dog pup. Credit: San Diego Shooter on Flickr

Since then, the taxonomic status of the New Guinea singing dog has been the subject of much controversy, and it has been reclassified several times over, some scientists suggesting it originated as a feral modern domestic dog (Canis familiaris), others suggesting it is a hybrid between the domestic dog and the Australian dingo. Over the past 50 years, it has been described as a species, a subspecies and a breed, but regardless, Koler-Matznick describes it as “an evolutionarily significant unit”. If further research does see it reclassified as a species or subspecies, says Hewitt, that could see conservation efforts ramped up, particularly in New Guinea. At the moment, conservation efforts are concentrated in the U.S., where several zoos are breeding captive Singers.

“With the proper efforts, I would say the future could be good,” says Hewitt of the fate of the wild Singer population. “The highlands are vast and open and little populated. Previously nomadic tribes are now settled and growing more food in the village, so I presume hunting is less than it was, [which is] good news for the dogs and the dogs’ wild food. But it may be different in Papua New Guinea, and indeed both sides are so badly governed, that anything is possible in the longer term, especially as the mountains are very rich in vast amounts of valuable untapped minerals. Money talks, and if a price can be put on the value of these animals, then something can be done, I would hope.”

Here’s a video of a very vocal female Singer at the San Diego Zoo:

Thanks to Mongabay.com for the tip. Read more about the trip at Tom Hewitt’s blog.

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Etheostoma stigmaeum. A new examination of the species has revealed the existence of five new darter species. Copyright: Joseph R. Tomelleri, used with permission

Getting a second term is pretty good, but getting your own fish is arguably pretty good too because Obamafish. Say it out loud, it’s great.

Five new species of colourful, freshwater fish called darters have been discovered in river drainages in eastern North America and named after four Presidents and a Vice. Darters are the smallest members of the perch family, and are named after their ability to zip around, under and into rocks and sediment on the beds of clean, fast-moving waterways.

Almost 200 darter species have so far been discovered, most of which live in the rivers and creeks of northern Alabama and eastern Tennessee. They are one of the most diverse groups of native North American fishes, and range from having healthy population numbers, such as the rainbow darter (Etheostoma caerelum) of Ohio, to being extremely rare, with some species sustained by a single waterway. Fewer than 50 diamond darters (Crystallaria cincotta) have been caught in the past 30 years, and their tiny, vulnerable population has been restricted to Elk River of West Virginia, while the Maryland darter (Etheostoma sellare), found in a particular creek in Harford County, Maryland, has been named one of the world’s rarest fish.

While conducting what would become the first comprehensive examination of breeding colour variation among populations of the common speckled darter (Etheostoma stigmaeum), a wide-ranging species that runs through Tennessee and Arkansas to Georgia and Louisiana, Steve Layman from Geosyntec Consultants in Georgia and Rick Mayden from the Department of Biology at Saint Louis University discovered that some of these populations were so different, they were actually separate species.

“We collected live breeding males (in the spring), photographed them, and took detailed colour notes throughout the range of E. stigmaeum and the other species in the subgenus (Doration),” says Layman. “What we found was those populations in the highland drainages of Tennessee, Kentucky and the Ozarks were quite different in colouration from the populations of E. stigmaeum from Gulf coastal drainages and the lower Mississippi River basin.”

Darter males are known for their brilliant colouring, especially during breeding season, which helps scientists to identify them. Some are jade green with yellow stripes, others are patterned all over with blues, reds, yellows and hints of purple. The speckled darter is particularly striking, with small, orange spots sprinkled over a light turquoise body, with thick turquoise stripes running vertically down the length of its body. Its first dorsal fin, which is the large fin that sits just higher than the middle of its back, is decorated with two turquoise bands flanking a large, bright orange band.

Layman and Mayden compared the colour of E. stigmaeum’s face and the distribution of orange spots on the soft dorsal fin, which sits behind the first dorsal fin, to fish in the various populations they studied to distinguish them as new species. The anal fin, which sits at the lower end of its underside, and the caudal fin (tail), revealed further disparities. Morphological features also came into play, as scale rows, fin rays and sensory pores were counted and the presence or absence of tiny teeth on the upper jaw called palatine teeth were noted.

Etheostoma obama, a new species described by Mayden and Layman. Copyright: Joseph R. Tomelleri

The first of the new species to be described by the researchers in a paper to be published by the Bulletin of the Alabama Museum of Natural History is the spangled darter (Etheostoma obama), the males of which are resplendent in bright orange and iridescent blue spots, stripes and checks. Endemic to the Duck and Buffalo Rivers of the Tennessee River drainage, the males can grow up to 48 mm long, while the largest females reach just under 43 mm. Twenty-nine percent of the specimens observed had palatine teeth.

“We chose President Obama for his environmental leadership, particularly in the areas of clean energy and environmental protection, and because he is one of our first leaders to approach conservation and environmental protection from a more global vision,” says Layman regarding how he and Mayden chose its name.

Etheostoma gore. Copyright: Joseph R. Tomelleri

This is the Cumberland darter (Etheostoma gore), found in the Cumberland River drainage below the Cumberland Falls in Kentucky. While it looks very similar to the spangled darter in its male breeding colours, the Cumberland darter is smaller – the largest males stretching just 42 mm and the largest females 41 mm. Plus its spot counts were more inconsistent, and its fins featured more dark grey and white colouring. Genetic analysis also suggests that no gene flow is occurring between it and the spangled darter.

“Vice President Gore’s environmental leadership throughout his public service, and after he left office, contributed significantly to our society pivoting from regional environmental protection to a more global perspective on human impacts to our environment (global climate change),” says Layman. “He also has a geographic tie to the new species from the Cumberland River – Nashville, where he is from, is located along the Cumberland River.”

Etheostoma jimmycarter. Copyright: Joseph R. Tomelleri

The bluegrass darter (Etheostoma jimmycarter), named after the ‘Bluegrass State’ in which it was found, sports an even duskier colouring through all but its caudal fin, with a more solidly turquoise cheek. It was found in the Green River drainage of Kentucky and Tennessee, and the species spreads widely to the upper Barren and upper Green Rivers and the Rough River. It’s a relatively large species, the largest males growing to 49 mm long, and the largest females 46 mm.

“President Carter preserved lands for wilderness protection, established a natural energy policy (signed into law the Department of Energy), and since leaving office has made tremendous contributions globally through his humanitarian work,” says Layman.

Etheostoma teddyroosevelt. Copyright: Joseph R. Tomelleri

Another small species in the bunch, the highland darter (Etheostoma teddyroosevelt) can grow up to 43 mm if male, and 41 mm if female. Its lower lip is distinctively grey, and 16% of the specimens observed had palatine teeth. It was named after its home in the ozark highlands in Arkansas.

“President Roosevelt will always be known for his legacy of preserving vast areas for national monuments, parks, forests, and refuges, setting a precedent that many other presidents would follow (not only these particular leaders),” says Layman.

Etheostoma clinton. Copyright: Joseph R. Tomelleri

And finally, here’s the beaded darter (Etheostoma clinton), whose males eschewed the more solemn grey and black trimmings of the former three species for a rich blue-green hue. The biggest this little fish can grow to is just over 34 mm, the males only ever so slightly larger than the females, and palatine teeth were found in 100% of the specimens observed. It is known only from the upper Caddo and upper Ouachita Rivers of Arkansas, and the researchers named it after the unique dark grey band that runs along its body through the line of turquoise blue blotches, suggesting a string of beads.

“President Clinton also preserved millions of acres of wilderness, enhanced environmental protection of national forests, and has a geographic tie to the new species from the Ouachita highlands in Arkansas,” says Layman. “We admire these American leaders for their vision, leadership, and commitment to conserving our natural resources and protecting the environment for future generations.”

According to Layman, a genetic survey of the different species indicated that each of them is travelling on a separate genetic pathway, and their geographic distributions and the patterns of species relationships can be used to test biogeographic theories explaining how the species ended up where they did.

“If different groups of fishes inhabiting the same rivers show congruent patterns of species relationships, then these patterns may suggest how historical changes in drainage patterns of rivers (dating to pre-Pleistocene glaciation) may have provided geographic isolation eventually leading to speciation,” he says. “Darters are especially informative in this regard, because many species are restricted to single river basins in separated highland regions (east and west of Mississippi River) having complex drainage histories that were never glaciated.”

While none of these newly identified species currently warrant protected status, there are many factors that could change their situation. According to Layman, the most common threats to these and other species of darters include habitat alteration and fragmentation from dams; sedimentation of clean stream bottoms from land-disturbing activities, agricultural runoff, and urbanisation; changes in hydrology associated with developed land uses; and water quality degradation from point and non-point sources. “There is currently no concern about the population numbers in the wild of these five new species,” he adds.

Hat-tip to the Tennessee Aquarium Conservation Institute blog.

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Imantodes chocoensis, a new species of blunt-headed vine snake. Credit: Omar Torres-Carvajal et al.

A new, weirdly proportioned species of snake called Imantodes chocoensis has been discovered in the tropical region of Chocó, which lies on the Pacific coast of northern Ecuador, Colombia and Panama.

It belongs to the Imantodes genera of snakes, of which there are only six other known species. Otherwise known as blunt-headed vine snakes, Imantodes have a very distinct look, with blunt-ended heads; big, sometimes almost googly, eyes; long, slender bodies and rather disproportionately thin necks. Some species, such as the blunt-headed tree snake (Imantodes lentiferus) from Brazil, look downright cartoony due to their very odd proportions.

Imantodes are delicate, nimble and nocturnal, and live in the trees of Mexico, Central and South America, using the weight of their lower bodies to fling their heads and upper bodies effortlessly from branch to branch. To hunt, they press the lower third of their bodies, which is where the internal organs are kept, against a branch for support to free their heads and the rest of their bodies for snatching up prey such as lizards and frogs. Only mildly venomous, these non-aggressive snakes inject their toxins using enlarged rear fangs positioned much further down the upper jaw than the more common frontal fangs of viper and cobra snakes.

Discovered by a group of zoologists led by Omar Torres-Carvajal from the Museo de Zoología QCAZ in Ecuador on 24 April 2007, I. chocoensis was described based on several live individuals and preserved specimens that have been sitting in a number of Ecuadorian and American natural history museums, unidentified since 1994. Also known as the the Chocoan blunt-headed vine snake, it was distinguished from its relatives through an analysis of its DNA, morphological features, and colour patterns.

Imantodes chocoensis' head, showing the absence of a loreal scale. Credit: Omar Torres-Carvajal et al.

What makes this new species truly unique is the absence of what’s known as the loreal scale. The lore is the region in birds, reptiles and amphibians between the eyes and nostrils, so this is where the large loreal scale sits, flanked by the preocular scale closest to the eye, and the prenasal scale next to the nostril. Every snake in Colubridae family, which contains around 65% of all living snake species, has a loreal scale, but I. chocoensis just has one big preocular scale and two postoculars (the extra one is tiny).

Stretching no more than 107 cm long,  I. lentiferus is patterned with whitish cream, copper, dark brown and black hues. Its huge, bulging eyes take up 27% of the total length of its head. Sex is determined by the presence of hemipenes, which are the snake and lizard equivalent of the penis. This elusive organ is kept inverted inside the tail until required, and in I. lentiferus’ case, is relatively long (11.2mm) and covered in large, prominent spines and several rows of smaller ones to assist the males in anchoring themselves inside the females.

The spiny hemipenis of Imantodes chocoensis. Credit: Omar Torres-Carvajal et al.

Torres-Carvajal and his team’s analysis of I. chocoensis, published in the current issue of ZooKeys yesterday, revealed that it is so closely related to the blunt-headed tree snake (Imantodes lentiferus), they have been declared sister species. Torres-Carvajal suggests that the two could share an ancestor species whose population was split in two and forever divided with the rising of the Andes.

Here’s a video of Andrew Gray, Curator of Herpetology at Manchester Museum, handling a yellow blunt-headed snake, Imantodes inornatus, in Costa Rica:

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Illacme plenipes, the animal with the most legs in the world. Credit: Paul Marek et. al.

*Insert Angelina Oscars Leg joke here*, but the leggiest animal in the world is actually the millipede Illacme plenipes, and researchers have published the most comprehensive analysis of the species’ anatomy, including what it does with its record 750 legs.

Illacme plenipes means ‘in highest fulfillment of feet’, because the females of the species have the most legs of any animal in the world, including the other 9,999 known species of millipede. The species was first described in 1928 by O. F. Cook and H. F. Loomis from the U. S. Department of Agriculture, based on seven specimens found in Central California. No photograph, illustration or clear location description was provided in the original report, so I. plenipes was not seen again in the wild till almost 80 years later, when millipede expert Paul Marek from the University of Arizona and his brother set out to find one for themselves.

Using a number of mapping technologies including Google Maps, the pair managed to rediscover the extremely rare I. plenipes on 29 November 2005 under a large, moss-covered sandstone boulder in San Benito County, California. “To find this species in particular, one believed extinct over the past 80 years and this relict animal with 750 legs, was wonderful,” says Marek. “To tell you the truth, and this is the experience every time I find a species I’ve never seen before, it was an exhilarating experience. Even when reading about other entomological discoveries (whether it be the Lord Howe Island stick insect or bioluminescent cockroaches) it’s exciting to think about all the fantastic and diverse life forms that live with us on the planet.”

Marek announced the species’ rediscovery in a 2006 issue of Nature, and released the first-ever video footage and scanning electron micrograph images of the cream-coloured arthropod. He discovered three more I. plenipes millipedes in December 2005, January 2006 and December 2007, all under sandstone boulders, and has described every inch of the species in ZooKeys today.

Oak forest understory habitat of I. plenipes. Top, base of sandstone pinnacle, where specimens were found. Bottom, mossy oak forest—close-up of habitat where I. plenipes individuals were encountered. Credit: Paul Marek et. al

I. plenipes belongs to the pan-tropical order Siphonophorida, which spans Central and South America, South-East Asia and Australasia. It is the only representative of the family Siphonorhinidae in the Western Hemisphere and its habitat spans just 4.5 km in diameter in the northwestern foothills of the Gabilan Range in San Benito County, just south of San Francisco.

Marek and his team distinguished their specimens from other millipede species based on an anatomical analysis, taking particular interest in the genitals. “For this relict species in particular, and especially since there’s nothing like it in the Western Hemisphere, [distinguishing the species] is pretty straightforward. It’s so completely different, anatomically, from anything else in the area,” he says. “For questions about species that are more closely related to one another, millipede taxonomists use the anatomical differences in the genitalia under the lock-and-key hypothesis – in a crude way, ‘the idea that a lock from one species cannot be opened with a key from another’.”

I. plenipes has no eyes, and shuns the light to live in subterranean environments 10 to 15 cm beneath the soil. Not only does it have more legs than any other known organism, it has huge antennae relative to its body size – just 3 to 4 cm long and about 0.5 mm wide – and is covered in little hairs that secrete a viscous silk-like substance. The lower third of its gut, called the metenteron, spirals fully visible through its translucent exoskeleton, which can be built of up to 192 body segments, and unlike the beak-like mouthparts of other millipedes in its family, I. plenipes‘ mouthparts are rudimentary and fused to leave just a small opening for sucking up fluids. “A spiraled metenteron coupled with the extreme number of segments lengthens the digestive tract and hence the body. This lengthening might function to increase the absorptive surface area in order to extract maximum benefit from a water or nutrient-deficient diet,” the researchers suggest, but just what this diet consists of remains unclear.

Illacme plenipes female with 170 segments and 662 legs. Magnified view of posterior segments with corkscrew-shaped metenteron visible through cuticle. Credit: Paul Mark et. al.

The females of the I. plenipes species can have up to 750 legs, whereas the males sport a maximum of 562. Millipedes in general use their many legs to burrow around obstacles in their environment, each pair of legs acting to push and propel their little bodies through in the earth. Marek and his team suspect that the I. plenipes millipede has an exceptional number of legs to move around its subterranean habitat, and also to help it cling tightly to the undersides of the sandstone boulders found exclusively in the area. Its sticky, silk-like secretions could also help to adhere them to the boulders, but as the secretions increased with handling, the researchers suggest they could also act as a defence mechanism.

Scanning electron micrograph image of Illacme plenipes' head and antennae showing the unusual covering of hairs. Credit: Paul Marek et. al.

The future of this very rare species is uncertain, due to its limited habitat and what appears to be low population numbers. “Exploitation as a result of over-collecting, [is] something that we were cognisant of and tried to avoid while gathering information about these millipedes, [and the] loss of this species’ habitat and extinction is a real possibility,” says Marek. “The idea with conservation is to preserve as much biological diversity as possible, and not only is this species so different than anything else in the area, the habitat that it lives in is filled with so many different and unique species – things that we know so little about. There are wonderful creatures in this area. Animals like trapdoor spiders, slugs, beetles, salamanders and scorpions. Plants like giant draping oak trees, ferns, mosses, and a number of different fungi and flowers. Many of these species are found here in this limited area, and no place else on earth.”

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Chondrocladia lyra, a new species of carnivorous harp sponge. Credit: MBARI

You may remember the Monterey Bay Aquarium Research Institute (MBARI) from such discoveries as the Yeti crab, the squid with elbows and my personal favourite, the pigbutt worm, and now they’re back with footage of a new species of carnivorous sponge.

Seventeen years ago, Jean Vacelet and Nicole Boury-Esnault from the Centre of Oceanology at France’s Aix-Marseille University provided the first real evidence that a sponge could be more than, well, a sponge. They had discovered a new species of deep-sea sponge living in the unusual setting of a shallow Mediterranean sea cave, the inside of which mimicked the conditions of its usual habitat more than a kilometre below the surface. This allowed the researchers an unprecedented view of the sponge’s eating habits, and they watched as it snared its prey of small fish and crustaceans instead of absorbing bacteria and organic particles through their bodies, like most other sponge species do – including ones living in the very same cave.

Vacelet and Boury-Esnault’s sponges were of the Asbestopluma genus and belonged to the Cladorhizidae family of carnivorous demosponges – the class that contains over 90% of the world’s sponges. Since reporting their discovery in a 1995 issue of Nature, 24 new species of cladorhizid sponges, including the incredible ping-pong tree sponge (see below), have also been discovered. Yet due to the difficulty of studying their behaviour at such incredible depths, researchers have had little opportunity to describe essential aspects of their lives, particularly how they reproduce.

Chondrocladia, or ping-pong, sponge. Credit: MBARI

Which is where MBARI’s remotely operated vehicles (ROVs) Tiburon and Doc Ricketts, come in. Using these deep-diving vessels, a team of researchers led by Senior Research Technician Lonny Lundsten discovered a species of harp sponge called Chondrocladia lyra off the coast of California, at depths of 3316–3399m.

As Mr_Skeleton pointed out on Reddit this week, this sponge doesn’t look like it could clean anything. But it can catch prey, envelop it in membrane and digest it whole, so it certainly has other priorities. Based on footage of several individuals and two large, fragmentary specimens brought up by the ROVs, Lundsten’s team described how the vertical branches and horizontal stolons that make up the sponge’s basic harp-like structure, called a vane, are covered in barbed hooks and spines. They found that a number of crustacean prey were passively ensnared on these branches thanks to the Velcro-like hooks and then aggressively enclosed in a cavity to be dismembered into small, digestible particles, which provided direct evidence of the species’ carnivorous appetites.

C. lyra can grow up to 37cm long – impressive for a sponge – and are anchored to the sea-floor by a structure called a rhizoid, which looks like a root system. They can have 1-6 vanes, each supporting a number of equidistant vertical branches, and each of these end in swollen terminal balls. According to the researchers, these terminal balls produce condensed packets of sperm called spermatophores, which are released into the surrounding water in the hopes of fertilising other harp sponges in the area. Each C lyra sponge also has an egg development area around the mid-point of the branches, and when the spermatophores make contact, these areas swell up as the eggs are fertilised and begin to mature.

The vertical branches of the harp sponge are tipped by swollen terminal balls containing packets of sperm. Credit: MBARI

The team suggests that the structure of the harp sponge is designed to ensure that they catch the most prey possible, and also maximise their chances of catching spermatophores from other harp sponges.

“Video footage taken as the ROVs approached specimens of C. lyra provided information about the biological diversity of the areas in which the sponges live,” the researchers added in their report in the current issue of Invertebrate Biology. “Among the coexisting invertebrates were unidentified sea anemones; the soft coral Anthomastus robustus, members of several species of sea pens; and the sea cucumber Paelopadites confundens, as well as another sea cucumber in the family Elipidiidae.”

Here’s some video footage of the new harp sponge:

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Illustration of the spade-toothed whale's general external morphology. Credit: Current Biology

We’ve got an actual photograph of it too, but it’s not pretty, so you might want to stop eating before you scroll down…

Considered the least known and rarest species of whale, and one of the world’s rarest living mammals, the spade-toothed whale (Mesoplodon traversii) has been seen for the first time after a mother and her male calf beached and died on a New Zealand beach.

Not only are beaked whales of the family Ziphiidae rare, their ability to dive down to exceptionally deep areas of the ocean in search of squid and other deep-sea fish means they are also very elusive. They can reportedly dive to more than 800m below the surface and dives can last up to 87 minutes. Superficially, beaked whale species look pretty similar, and for many of the 21 known species, we have frustratingly few records. So when a new beaked whale specimen is discovered, figuring out which species to assign it to can be quite a task.

Until now, we’ve only known about the spade-toothed beaked whale from a few bone samples, as no intact specimens have been discovered. This has made identifying the species extremely complicated. In 1872, a partially damaged mandible and set of teeth were picked up on Pitt Island, of the Chatham Island archipelago in New Zealand, and described by the director of the Colonial Museum of New Zealand at the time, James Hector, the following year. As no one had ever seen a spade-toothed whale before, Hector assigned the bones to the Scamperdown whale (Dolichodon layardii), which had been discovered eight years prior by British zoologist John Edward Gray. This species was the most commonly beached beaked whale around the New Zealand coast at the time.

Gray caught wind of this and examined the bones himself, and in 1874 assigned them to an entirely new species, which he called Dolichodon traversii. The correct genus was a point of contention for these whales, so Dolichodon traversii was later corrected to Mesoplodon traversii. In response to Hector’s analysis, and explaining the need to name a new species, Gray noted that, “‘Mesoplodon layardi (or as I should call it, Dolichodon layardi) has a much longer and attenuated lower jaw, and much more slender teeth than the Chatham Island specimen”, in Transactions of the New Zealand Institute (PDF).

When two spade-toothed whales washed up on a New Zealand shore, they were mistaken for the more common Gray's beaked whales (pictured here) because, superficially, the species are very similar. Credit: New Zealand Government

During the 1950s, a second beaked whale specimen was collected on New Zealand’s White Island and stored in the MacGregor Collection of the University of Auckland. After a flurry of analysis, both genetic and morphological, from 1999 to 2002, the skull bone specimen was assigned to a number of different species including Bahamonde’s beaked whale (Mesoplodon bahamondi). Bahamonde’s beaked whale was known from a damaged skull bone found in 1986 on Robinson Crusoe Island in Chile. Finally, in 2002, new research by a team led by Anton van Helden from the Museum of New Zealand Te Papa Tongarewa unified the Pitt Island, White Island and Robinson Crusoe Island specimens as belonging to the one species, and suggested that Bahamonde’s beaked whale was actually the same species as Mesoplodon traversii.

“Our results combine morphological and molecular evidence to unify three fragmentary and disparate museum-held beaked whale specimens resulting in the synonymy of M. bahamondi with M. traversii,” the team wrote in Marine Mammal Science (PDF). They gave M. traversii the common name, the spade-toothed whale, which refers to its extraordinary teeth that are shaped like “the oblong blade of a fensing knife (known as a ‘spade’) used by North American whalers in the 19th Century”. Thanks to the discovery, New Zealand gained the reputation of being the richest region in the world for beaked whale species diversity.

So after many years, the enigmatic spade-toothed beaked whale had three sets of specimens – two adult skull fragments, adult teeth and a mandible – assigned to it, but besides the basic skull morphology, no one knew much of anything about it.

The unfortunate adult female spade-toothed whale that was found dead and beached on Opape Beach in 2010. Credit: New Zealand Department of Conservation

In December 2010, an incredible discovery was made when two whales stranded themselves and died on Opape Beach in New Zealand. The adult female was 5.3m long and the young male was 3.5m long. Initially identified as the common Gray’s beaked whale (Mesoplodon grayi), a team of researchers led by Kirsten Thompson from the School of Biological Sciences at the University of Auckland sequenced two mitochondrial DNA regions and compared them to the existing three bone specimens to discover that these were never-before-seen spade-toothed whales.

The researchers also figured out what distinguished the spade-toothed whales physically from other species, having seen the species’ external flesh for the first time. They noted that the colouration of the rostrum, or ‘beak, is dark gray or black, rather than the white of the adult Gray’s beaked whale. It also has a dark eye-patch, white belly and dark flippers.

The team credited the discovery to New Zealand’s long-term and coordinated response to whale strandings, where they are reported regularly by the public to the Department of Conservation, whose researchers collect information and tissue samples from each one. The government has now accumulated some 20 years’ of tissue samples and records on a number of species.

We still have no idea how many of these whales exist in our oceans, but, the researchers conclude in Current Biology today, “We can now confirm that the spade-toothed whale is extant and for the first time we have a description of the world’s rarest and perhaps most enigmatic marine mammal.”

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