Friday mystery object #398 answer

Happy 2021 – I hope you had a great celebration!

Last year I gave you this mystery skeleton for you to have a go at identifying:

That erect stance and those super-short and chonky wing bones are a dead giveaway that this is one of those charismatic flightless waiter birds (and before you ask, yes the “i” is intentional).

There are around 20(ish) species of penguins or pengwings if you’re Benedict Cumberbatch.

Although the various species look superficially similar, with their black and white base colour scheme and tubby yet streamlined shape, they do have some distinguishing characteristics. Unfortunately, the most obvious relate to plumage and that’s missing here.

Size can help with narrowing it down – and this particular specimen is small. Admitedly it’s hard to tell that without a scale bar, but the large species have relatively small skulls in proportion to their body size, so they can be ruled out.

Bill length and shape can also provide some good indications even from non-skeletal birds and you can of course check out my favourite online resource (SkullSite.com) to see skulls of most of the main penguin genera, if not all the species (yet!). In the comments, James Bryant and Wouter van Gestel (creator of the aforementioned SkullSite) recognised that this is a Little, Blue or Fairy Penguin Eudyptula minor (J.R.Forster, 1781).

Little Penguin in the Melbourne Zoo. Image by fir0002, 2009.

This is the smallest species of penguin, it has breeding colonies in Australia and New Zealand and the population on Phillip Island has become a bit of a tourist attraction. They feed on small fish, like anchovies and pilchards or small invertebrates including squid and jellyfish.

There will be more mystery objects to come for 2021 – let’s hope this year works out better for everyone than 2020…

Friday mystery object #397 answer

I’m going to start this week’s blog mystery object with an apology – it’s going to be a short one, as I’m in the final throes of taking down our Fin whale, which means I’m exhausted after several long weeks of hard graft. Check out the #DeadZooDiary hashtag on Twitter if you want to get an idea of what’s involved.

Last week I gave you this somewhat smaller skeleton from the Dead Zoo to have a go at identifying:

It wasn’t too difficult to narrow it down to one of a few species, thanks to the very distinctive knee region.

There are only a small number of birds that have adopted this extreme elongation of the cnemial crest on their tibiotarsus and patela. These are all specialist foot-propelled swimmers that need that long lever to help power their diving strokes. This is a feature limited to just the grebes and the loons/divers.

Most people figured out that this is the skeleton of one of the loons. The skull provides some clues, but unfortunately the angle of the photo doesn’t make it easy to figure out which of the five species it is.

The scale does rule out the larger of the species (Gavia immer or G. pacifica), but there are three other possibilities. For me the postorbital region suggests that this is the Arctic Loon Gavia arctica (Linnaeus, 1758), which fortunately matches the label.

I hope you enjoyed this weird kneed bird – congratulations to Goatlips and everyone else who figured it out!

Friday mystery object #396 answer

Last week I gave you this bumpy little critter to identify:

I think everyone recognised the mystery object as some kind of Nudibranchia or sea slug. The general type of sea slug is identifiable by that ring of gill filaments known as a branchial plume that you can see at the top of the specimen. This is characteristic of the suborder Euctenidiacea, also known as the dorids.

I called it bumpy, but if you look closely you’ll see that the bumps are pinched at the base and actually look rather warty. There’s a clue in that – and several of you spotted it.

There were a number of wart-related nudibranch suggestions that were close, but jennifermacaire was spot on with her comment:
Doris has warts?

This is indeed a Warty Dorid or Doris verrucosa Linnaeus, 1758.

Warty dorid, image by AndyT

This specimen isn’t quite as faded as everyone expected – they’re usually a fairly muted orange, yellow or a greenish colour, not too different to the mystery object. This probably serves as camouflage against the background of the Warty Dorid’s favourite food, the Crumb-of-bread Sponge, which also varies in colour from bright yellow to darker shades depending on the depth of the water in which they live.

More mystery objects next week!

Friday mystery object #395 answer

Last week I gave you this specimen from the Dead Zoo to have a go at identifying:

There were some great suggestions, some alluding to the tusk-like shape and structure, but the first person with a correct identification was Tony Irwin with an anagram of “Kuphus“. If you’re not familiar with the Giant Shipworm Kuphus polythalamius (Linnaeus, 1758), it’s a genus of boring mollusc that has proved to be rather interesting.

It’s in the shipworm family, but until recently it was only known to science from large, empty tubes like this one that washed up on a few beaches in the Philippines. That all changed 2016 when some live specimens were found and researchers were able to take a closer look at the biology of these surprising animals.

Unlike other shipworm, it turns out that Kuphus doesn’t eat wood. Instead it burrows into sediment and has a symbiotic relationship with bacteria that live in its gills, which metabolise hydrogen sulphide. This is quite a big deal, since it seems to provide an example of one set of symbionts (those able to digest cellulose in other shipworms) being replaced by a very different set capable of metabolising inorganic chemicals.

This change in relationship allows Kuphus to utilise in a different habitat type and may provide a clue as to how some of the organisms present along mid-ocean ridges have managed to adapt to a habitat far away from sunlight and largely removed from normal organic inputs.

It’s odd to consider that this specimen has been in the Dead Zoo since 1879, but we never knew just how interesting the species is until so recently. I wonder what other revelations we’ll come across as we carry on with our decant?

Friday mystery object #394 answer

Last week I gave you this mystery object to have a go at identifying:

Clearly it’s some kind of sea-star, but there are a LOT of different species .

Remarkably, that doesn’t seem to have posed a problem. The five stumpy arms narrowed it down to one of the cushionstars or biscuitstars and it seems that was more than enough for some of you.

Salliereynolds flagged one of the diagnostic features and dropped a hint to the species name:
“Six lumps to a side? From down under?”

But Goatlips took the mystery object to a whole new level with a biscuit recreation:

This specimen is a Southern Biscuit Star Tosia australis Gray, 1840. Probably not as tasty as an actual biscuit, but certainly very biscuity in appearance.

A short answer today I’m afraid, but it’s been a difficult week and there’s a lot to do in the Dead Zoo this Friday!

Friday mystery object #393 answer

Last week I gave you this specimen from the Dead Zoo to have a go at identifying:

It was a bit mean of me to not include a scale, but several of you managed to work it out regardless.

The overall group is fairly easy to spot, since it has 10 legs, the front pair bearing claws (or chela if you want to get technical) and the main body area is rounded. So it’s a crab.

In addition, the long legs and small body give it an overall shape reminiscent of a spider, so it’s a good bet that it’s some kind of spider crab.

Now, there are quite a lot of types of spider crab out there, but that sub-triangular body shape and those long legs help narrow down the possibilities further. In fact, it does share some similarities to the gigantic Japanese Spider Crab.

Japanese Spider Crab specimen at American Museum of Natural History. Image from Popular Science Monthly, June 1920

Unlike the Japanese Spider Crab (which was suggested), this doesn’t have extremely elongated chela. So not one of them. It’s also way too small, although my lack of a scale bar doesn’t make that obvious – sorry! However, the mystery object is in the same family (the Inachidae).

Once you start looking at the genera in the Inachidae there’s only one that matches the mystery object’s proportions, and that’s the Macropodia. Once you get that far, it becomes a case of discounting possibilities based on much more detailed features.

The Marine Species Identification Portal is a fantastic resource for checking this finer level identification. Going through the various species descriptions in there helps spot the key features for distinction between species.

In this case, the mystery object is particularly similar to M. tenuirostris and M. rostrata and it’s mainly the shape of the carapace around the ‘shoulders’ where the chela attach to the body that help confirm this to be the Long-legged Spider Crab Macropodia rostrata (Linnaeus, 1761).

So it was a good effort for everyone who managed to get this to family level, I congratulate those who worked this out to the genus and I doff my hat to anyone who managed to identify it to species. So jennifermacaire, my hat is doffed!

Friday mystery object #391 answer

Last week I gave you this skull from the Dead Zoo to have a go at identifying:

I think it’s quite a distinctive skull, so I didn’t provide a scale and I asked for cryptic clues to avoid spoiling the challenge.

The overall skull shape is fairly standard for an Artiodactyl, but while this specimen has no incisors in the upper jaw, there are fairly obviously empty alveoli that show where the teeth used to be. That means it’s not a member of the Ruminantia (the deer, antelope, cattle, giraffes and weird deery-antelopey type critters like chevrotains) since they all lack upper incisors.

That leaves the pigs, hippos and camels – and it’s clearly not one of the pigs or hippos.

The camel family is a bit odd. There are three wild species, but then an additional four entirely domesticated species. The proportions of this skull are a bit long for a Llama, Guanaco, Alpaca or Vicuña. That leaves the Dromedary, Wild Bactrian or Domesticated Bactrian camel as possibilities.

Dromedary skulls tend to have a horizontal nasal region then a steep rise to the braincase immediately behind the orbits, but this specimen has a more gentle slope running from the nose to the top of the braincase, so it’s Bactrian.

Unfortunately the Wild Bactrian camel is critically endangered and poorly represented in collections, so it’s hard to find enough comparative material to differentiate the wild and domestic Bactrians.

Well done to everyone who figured out that this is one of the double-humped ships of the desert. There were some great clues in the answers!

Friday mystery object #390 answer

Last week I gave you this specimen from the Dead Zoo to have a go at identifying:

It came from a cabinet of cave bones, but Nigel Monaghan (Keeper of the Dead Zoo) wasn’t convinced that this specimen was actually found in a cave.

Partly that’s because it’s a fairly fragile specimen with poorly fused sutures – these don’t usually stay connected in cave deposits, but also because it’s from a species that you wouldn’t expect to find in the kind of caves that the rest of these collections came from. So what is the species?

I don’t think this is a very difficult one since I’ve done very similar specimens before (regular visitors should have had an advantage), so I was looking for cryptic or entertaining answers – and I was not disappointed. Tony Irwin got a great clue in, with a pun that reflected the genus:

I think we need to focus (did I spell that right?) on the shape.

It is of course the skull of a seal in the genus Phoca – and the blunt shape of the anterior portion of the auditory bulla suggests to me that it’s a Harbour Seal Phoca vitulina Linnaeus, 1758 rather than the very similar Spotted Seal, which has a slightly more accute angle on the anterior auditory bulla.

So well done to everyone who figured it out! Now we just need to figure out how it either got into a cave or (possibly more likely) got put into the wrong cabinet.

Friday mystery object #389 answer

Last week I have this mystery object from the Dead Zoo:

I made it a bit harder than necessary by not including a scale, but then that’s part of the fun – and I think a scale might have made it all a bit too easy.

There were a lot of suggestions about what it might be, mostly referencing some kind of seat / saddle or a patella. It’s probably just about big enough to sit on, although I’m not sure it would be comfortable.

But quite a few of you did figure out what bone it is and more or less what kind of animal. It’s the manubrium (part of the sternum) of a young Humpback Whale Megaptera novaeangliae Borowski, 1781.

Here’s the specimen with our Conservator Silvia for scale next to the manubrium (it’s a little hidden by the bar supporting the mandible here). Silvia’s been busy cleaning the whale, ready for it to be dismantled in the next few weeks.

All the activity around this whale work has been keeping me busy, so I apologise for tardy replies to questions and slightly sparse answers. If you want to see what we’ve been up to, check out the #DeadZooDiary!

Friday mystery object #386 answer

Last week I gave you this taxidermy bird to have a go at identifying:

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It’s fairly obviously a duck of some sort, but there are almost 150 species in the duck family Anatidae, so that’s not really enough information.

Of course, the ornithologists were up to the challenge of working out which type of duck this was, with Wouter van Gestel dropping hints at a Steamer Duck. If you’re not familiar with Steamer Ducks, they are in the genus Tachyeres, there are only four species and they all live at the southern end of South America.

Of the four species, only one (the smallest) can fly. The others are very large, heavy and flightless. They sometimes use their small wings as a power assist in fast swimming, using a style reminiscent of an steamer ship’s paddles – hence the name.

The small wings on this specimen, as pointed out by Allen Hazen, suggest that this is one of the three flightless species, ruling out the Flying Steamer Duck T. patachonicus as a possible contender.

The three remaining species are all very similar and although some images online suggest that only one species has an orange bill, they all have quite a bright yellow-orange bill following their moult that becomes duller over time. Of course, when dealing with taxidermy you can’t fully trust things like leg or bill colour as they can rapidly fade after death and they are usually painted to give an impression of the natural colour – sometimes with a bit of artistic license.

This particular specimen is identified as Tachyeres cinereus, which is not a valid species, so I was hoping there would be someone with a useful morphological hint to help distinguish between species, but most ways of distinguishing rely on comparisons of bill length, mass and size.

However, this specimen does have a collection locality – the Falklands. There are two species of Steamer Duck that occur on the Falklands and fortunately one of them is the species that flies and has already been ruled out, so it seems likely that this is a Falkland Steamer Duck Tachyeres brachypterus (Latham, 1790).

Pair of Falkland Steamer-ducks. Image by In Vitrio, 2018

So well done to everyone who said it was a Steamer Duck – I think that’s about the best identification possible from the information provided!

On an unrelated note – over the next few weeks my mystery object answers may be a bit on the brief side. Projects at the Dead Zoo are underway that are taking up a lot of my time, so I may struggle to find time for detailed answers. If you’re interested in what I’ll be doing you’ll be able to check out the #DeadZooDiary hashtag on Twitter and Instagram, which we’ll be adding things to starting next week. Exciting things are underway!

Friday mystery object #384 answer

Last week I gave you this unusual looking skull to have a go at identifying:

mystery384

That low and elongated shape, combined with the large number of teeth and absence of a zygomatic arch – all within the context of the relatively large (but still quite small) size – all combine to narrow this down to just a few possible options.

There are a bunch of critters in what used to be called the “Insectivora“, back in the dim and distant days of my undergraduate studies. This wastebasket for things that look like they should be chasing acorns in a cartoon was rightly broken up into more meaningful cladistic groups during the great molecular taxonomic revolution in the dying days of the last century.

ice_age_png31

Scrat, a fictional sabre-toothed squirrel that looks like every third member of the old ‘Insectivora’

To be fair, there’s a reason why the “Insectivora” lasted as long as it did and why it took molecular research to finally tease the various groups apart. They don’t have many strong distinguishing anatomical features that are seperate them into clear higher level groupings. Sure, they look a bit different at the family level, but any higher than that and they smoosh into bunch of small toothy critters, many with no cheekbones to speak of.

However, some do have a zygomatic arch, such as the talpid moles and desmans, so it’s not one of them:

mystery330b-e1526623553591

Skull of European mole Talpa europaea Linnaeus, 1758

It also lacks the large orbits of something like a Sengi or Elephant Shrew:

Skull of a North African Sengi Elephantulus rozeti (Duvernoy, 1833).

It also lacks the well-developed sagittal and nuchal crest you’d associate with the Malagasy tenrecs:

Skull of a Tail-less Tenrec Tenrec ecaudatus Lacépède, 1799.

It also lacks the backwards projecting nuchal crest of a solenodon and it’s just too big for one of the true shrews – the largest of which is the Asian House Shrew with a skull length of around 38mm.

So this specimen isn’t as hard to recognise as it could be. The very flat top to the skull with the nostrils up high is a bit of a clue – something often (although not always) associated with aquatic animals. On closer inspection there are two likely suspects – the Web-footed Tenrec or one of the Otter Shrews (which are neither otters nor shrews).

The area around the occipital is a dead give-away here. The Malagasy Web-footed Tenrec Limnogale mergulus (Major, 1896) has an occipital region that’s hard to see in a side view, because the parietals extend down quite low, whereas the Otter Shrews have much higher parietal margin that exposes the occipital region – just like we see in the mystery object.

Finally, the size is give-away. As many of you recognised and hinted at (occasionally with some dodgy puns – I’m looking at you Tony), this is a Giant Otter Shrew Potomogale velox (Du Chaillu, 1860). These semiaquatic relatives of the tenrecs are unusual in how they swim, lacking webbed feet and relying on a laterally flattened tail to swim using a fish-like undulation. So well done to Jane, Tony Irwin, katedmonson, Allen Hazen, Rémi and everyone else who managed to work out this weird mystery.

Friday mystery object #383 answer

Last week I gave you this slightly mean mystery object from the Dead Zoo to have a go at identifying:

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I say it’s mean because it’s just a small fragment from the tip of the lower jaw. It does have some pretty distinctive teeth in it, so it’s probably not the most difficult mystery object I’ve shared, but it’s also from a species in a group of animals that are quite poorly known.

That said, Chris Jarvis was the first to comment and got it right immediately. However, there was a lot of subsequent discussion about how to be sure, given the poor representation of comparative specimens available and the similarities between this species and others in the family. That family is the Ziphiidae, which are the the Beaked Whales.

These cetaceans are rarely seen due to their deep water habits, sometimes diving to depths of nearly 3km (although more usually around 1km) to feed mainly on deepwater squid that they detect using echolocation. Most of what’s known about them comes from strandings – which is where this mystery specimen comes from.

The males tend to be smaller than the females, but the males of most of the 21 Beaked Whale species have tusk-like teeth that they probably use to fight over females, although the behaviour hasn’t been recorded, only deduced from scars and the behaviour of other animals with similar sexually dimorphic characters (there’s an interesting paper on the evolution of the tusks by Dalebout et al. 2008 is you’re interested [pdf]).

The teeth occur in different parts of the jaw and have a different shape depending on the species, so the fact these are located at the tip of the lower jaw means quite a lot of the species can be discounted. If you want to be able to do the narrowing down easily I recommend an old and somewhat unwieldy to navigate, but still very useful online resource – the Marine Species Identification Portal. If you can work out the navigation you can find small line drawings of the skulls of all species in lateral view.

Once you get that far it becomes easier to search for more detailed images of the couple of species it might be, which can yield some great 3D scans to help you work it out. Both Chris Jervis and katedmonson found examples and shared the links in the comments. Here’s a nice one from the NHM, London:

This species (the Cuvier’s Beaked Whale) clearly has bigger tusks than the mystery specimen, which you can see as a scan on the excellent Phenome10K resource*. The mystery object is the distal portion of the mandible of a male True’s Beaked Whale Mesoplodon mirus True, 1913. So well done to Chris Jervis for being the first to get in with the correct identification.

It may seem a bit odd to have just this small portion in the Museum, but as far as records go they represented a managable identifiable voucher for the stranding of the species in Killadoon, Co. Mayo, Ireland back in February 1983. These days we ask for even less material to keep track of strandings – just a small skin sample will do as long as it’s collected and recorded following the guidance of the Irish Whale and Dolphin Group’s (IWDG) Strandings Network.

These samples are stored in alcohol and form the Irish Cetacean Genetic Tissue Bank which is managed in partnership between IWDG and the Dead Zoo to provide genetic data for research into whales. It’s a fantastic resource, but I doubt that anyone could identify the species represented in the samples without access to a genetics lab. And that’s why I like bones best.

*A. Goswami. 2015. Phenome10K: a free online repository for 3-D scans of biological and palaeontological specimens. http://www.phenome10k.org.

Friday mystery object #380 answer

Last week I gave you this specimen from the “Unidentified” drawer in the collections of the Dead Zoo to try identifying:

mystery380

I don’t think anyone had much difficulty in identifying it, since it is quite a familiar and characteristic skull, but well done to everyone who worked out that this is a European Badger Meles meles (Linnaeus, 1758).

There are two other species in the same genus – the Asian Badger M. leucurus and Japanese Badger M. anakuma, so they also need consideration (skulls of all three species can be seen in this paper by Andrey Puzachenko). However, the Japanese Badger is a smaller and more delicately skulled animal and the Asian Badger can be distinguised by differences in the shape of the region around the bony bulbs that hold the ear bones (called the auditory bullae – in Asian Badgers they’re more obtuse and have a straighter lateral margin).

So apart from the distinction between two members of the same genus, this is a fairly straighforward specimen to identify, it makes me wonder why it wasn’t recognised in the collection? I think there are a couple of factors, which I’ll outline here.

The first is that the lower jaw (mandible) is missing. This is totally normal for almost any kind of animal skull you find, except these badgers, which have a well-developed bony process that locks the mandible into the long jaw articulation (known as the glenoid fossa).

Badger

Badger skull with mandible locked in place.

Glenoid

Detail of jaw articulation showing the main features. Red = mandibular articulation, Blue = inside of glenoid fossa, Green = glenoid process that helps lock the lower jaw in place.

This captive mandible is a dead give-away when you see it, but it does mean that when it’s missing it can be confusing.

A mature adult European Badger like this (as indicated by the well-developed sagittal crest) would also normally have extremely extensive wear on their molar teeth, due to the abrasive grit in the gut of their main diet of Earthworms.

Molars

Extensively worn upper molars of an adult European Badger

But the mystery specimen has remarkably little wear on those massive molars. This suggests that it probably had a different diet than is usual for a Badger from northern Europe – and no, not mashed potatoes. The same species in southern Europe has a different diet to their northern counterparts, dominated by insects and fruit, so I wonder if the specimen was collected during someone’s holiday to somewhere in the Mediterranean?

[UPDATE 28th April 2020. Several people have kindly shared images of their badger specimens and it seems that the level of wear in my specimen is not as common as I thought. In one discussion the issue of soil type was raised and I think that may play a big factor. This specimen came from Devon, in an area with sandy soil. Other specimens from areas with muddy or silty soils showed much less wear. This may be coincidence, but it would make sense that Earthworms with coarser soil in their gut would be more abrasive to eat and therefore cause more dental wear. That would be fairly straightforward to test using museum collections. If this hypothesis about wear is correct, then the mystery specimen could be from anywhere with soils that aren’t too sandy.]

I hope you found that useful, or at least a bit of a distraction from lockdown. Stay safe!

Friday mystery object #379 answer

Last week I gave you this rather nice, but somewhat tricky mystery object to have a go at identifying:

mystery379

As well as here on Zygoma, people were checking this out on Twitter, where it was shared under the #GuessTheSkull hashtag started by @Yara_Haridy. I strongly recommend checking it out if you’re on Twitter and also giving Yara a follow as she does some great stuff.

As to this specimen, despite the difficulty, several of you managed to work it out down to species level – which I think deserves a round of applause, because this critter is not very well-known and there are few resources out there with examples of their skulls.

So, working through the options, despite having a whiff of possum about it, it can’t be a marsupial because it doesn’t have holes in the roof of the mouth (aka palatal vacuities), a shelf on the inside of the mandible or a tearduct on the outside of the orbit (aka external lacrimal duct) – all of which are marsupial traits as illustrated on this Tasmanian Devil skull below.

MarsupialFeatures

The teeth are those of a carnivore (or perhaps I should say Carnivore) and the auditory bulla is single chambered, so it’s one of the caniform carnivores, rather than one of the feliforms (that long snout suggests the same). This rules out the cats, hyaenas, mongooses and the weird Malagasy carnivores like the Fossa.

From that point on it gets more difficult. Some people thought it was a bit foxy, but the lack of a well-defined post orbital process rules out any of the dogs and it’s clearly not a bear, seal or sealion. That leaves the members of the Superfamily Musteloidea, which includes mustelids, racoons, the Red Panda, and the skunks.

Quite a lot of people got busy searching through possibilities in the largest of those groups – the mustelids. However, most of this family have fairly short, broad skulls. Only the ferret badger skulls come close to this specimen and even they aren’t as narrow. Similarly, the raccoons and Red Panda’s have fairly broad and short skulls.

So that leaves the skunks and relatives in the family Mephitidae. That makes life much easier, since there are only four genera in the family and three of those have wider skulls than this. So that leaves one genus that only contains two species – Mydaus or the Stink Badgers.

That’s where it gets really hard. A few folks on Twitter and Allen Hazen on the blog comments managed to get it to genus (Allen also worked out that it’s female), but I was especially impressed by the efforts of Rémi and katedmonson who went that step further and managed to get the identification to species. Here are the features:

katedmonson said:

…Comparing the two, M.j. has the slender snout, and a larger infraorbital foramen than the M.m. The big decider for me was the tympanic bulla. They seem to match the M.j. but not the smoother M.m. Also, females in the M.j. are known to lack a sagittal crest, so my best guess is female M. javanensis. About 4 years old. That had just eaten 6 earthworms and two beetles. And she had a limp on her left hind limb. (just kidding about the 6 earthworms, it was only 3)

I’m not sure about the earthworms, beetles or limp and I personally think the age would be a little younger – maybe 2.5 to 3 years since the earthworms have a large amount of grit in their gut and that significantly increases dental wear in animals that eat them. However, I think the rest is spot on – this is indeed the skull of a female Sunda Stink Badger Mydaus javanensis (Desmarest, 1820).

Mydaus javanensis

Mydaus javanensis specimen at Museum of Natural History in Vienna. By U.Name.Me, 2018

These odd looking animals have habits similar to the European Badger, foraging on the ground and in the surface of the soil for invertebrates and small prey, and sleeping in burrows during the day. However, while Badgers can be a bit whiffy, these guys have a full-on skunk-like noxious spray from their anal glands.

I hope you enjoyed that challenge, there will be another next Friday and if you want some extra mystery skulls, don’t forget to check out #GuessTheSkull onTwitter.

Have a great Easter!

Friday mystery object #376 answer

Last week I gave you this guest mystery object from the Museum of Life Sciences at King’s College London:I thought it would prove tricky, as the specimen is from a juvenile animal, which always complicates things.

However, it didn’t take long for you to work out what it was and, if I’m honest, you beat me to it, so well done on that and thanks for your contributions!

Clearly it’s a carnivore as it has well-developed carnassial teeth. However, immature animals with a mix of deciduous and permanent teeth can be confusing. It also doesn’t help when the skull shape is still forming.Fortunately, to help narrow it down there is the auditory bulla and that molar tooth just behind the carnassial. The shape of these features suggest that it’s a mustelid.

There was some discussion about badgers and otters, but Bob Church settled it by providing a very useful reference containing this image:

Figure from Long, Charles A. 1965 Comparison of Juvenile Skulls of the Mustelid Genera Taxidea and Meles, with Comments on the Subfamily Taxidiinae Pocock. American Midland Naturalist 74(1)225-232.

As you can see, this is an excellent match for the mystery specimen, both in dental morphology, auditory bulla shape and even scale, allowing us to make a confident identification of juvenile American Badger Taxidea taxus (Schreber, 1777).

So well done to Jeanie, katedmondson, Bob Church and Rémi, and my thanks to you all for your help in identifying this tricky specimen.

Friday mystery object #375 answer

Last week I gave you this unidentified skull from the collections of the Dead Zoo in Dublin to have a go at identifying:

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I wasn’t sure how difficult this would be – I know carnivore skulls can be a bit of a challenge, but this is a critter that’s come up as a mystery object a couple of times before. As such, I did expect a few of the regulars to recognise this, but it proved more difficult than I thought.

That said, nobody got it. Well, somebody got it, but that person was nobody with the simple statement:

I’m guessing coati 🤔

Of course, there’s more than one kind of coati, in fact there are four: the Ring-tailed, the White-nosed (or Coatimundi), the Eastern mountain and the Western mountain.

The mountain coatis are in the Genus Nasuella and they have a very narrow and gracile rostrum (that’s the muzzle area) – so this is not one of them. The other two are in the Genus Nasua and they are recognisable by their upward tilted nasal area and their upper canines which are very tusk-like – projecting forward and triangular. The mature adults of both species have a big sagittal crest, which this lacks, but that’s probably because it’s not a mature adult.

Differentiating between the two species can be tricky, but the region around the auditory bullae can be useful in this. The Animal Diversity Web has some very useful images that can help.

The slightly more inflated auditory bullae and the angle of the mastoid process (where the muscles that control the movements of the outer part of the ear attach to the skull) tells me that this is most likely to be the White-nosed coati Nasua narica (Linnaeus, 1766).

I hope that helps in case you need to identify another of these any time soon.

Friday mystery object #374 answer

Last week I gave you this ‘unidentified bone’ to have a go at identifying:

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I say bone, but as was pointed out on Twitter, perhaps the label reads something else…

‘Boner’ would of course be an accurate slip, because this is clearly a baculum (aka the penile bone, os penis, os priapi, or oosik in the case of pinnipeds). I don’t think the slip was deliberate though, since I removed a piece of information from the label for the sake of the challenge:

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I can only imagine that this baculum was found with some seal bones and was not recognised as being part of the skeleton and therefore removed. There’s no reference to where the rest of the seal bones are, which is bit of a problem if they are in the collection.

I’ve blogged about penile bones on several occasions, since as far back as in 2010.  Bacula are often quite distinctive, allowing species identifications based on their morphology. But this particular specimen has proven hard to find good specific comparative material or images (online or in publications) to do comparisons against.

However, from looking at the few seal bacula that do have illustrations in publications, and scouring the internet for articulated seal skeletons with bacula in place, I think it’s probably from male Grey Seal Halichoerus grypus (Fabricius, 1791). If so, this individual would have likely been aged 10 years or over.

This age suggestion is based on the length and robustness of the specimen, which in Grey Seals has been shown to correlate quite closely with age and maturity in the males (Hewer, 1964; Van Bree, 1972). This interesting bit of information aside, I unfortunately couldn’t find the clues that led palfreyman1414 to the Holmesian deduction:

…So, apart from the fact that they are right-handed, have been to Afghanistan, currently work as a haberdasher’s spool threader and have fallen on hard times, I got nothing.

But bacula are informative bones, so I’m sure there is a lot of additional information available from the specimen that I’ve not deduced.

All of you worked out what this bone(r) was, and several people recognised it as being from a seal of some kind, both in the blog comments and on Twitter. There was also a suggestion of Grey Seal from Conor Ryan:

I hope you had fun with this mystery boner! Oh wait, that sounds really wrong.

 

Friday mystery object #373 answer

Last week I gave you this pretty cool skull to have a go at identifying:

 

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As everyone recognised, it’s the skull of a snake. I think that’s clear from those extremely long quadrate bones (highlighted in purple in the top view), with which the lower jaw articulates to allow a huge gape for swallowing prey whole. However, there are a lot of snakes out there – around 3,600 species, which means there are lots of possibilities for the species that this particular skull belongs to.

The side view allows us to rule out quite a few possibilities, since it’s clear from the teeth that this isn’t one of the front-fanged snakes (vipers and elapids).

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Rattlesnake skull, with its big front fangs.

The light construction of the skull suggests it’s not one of the constricting snakes, which have much more robust skulls for dealing with the forces generated by the struggles of relatively large prey.

PICT0159

Python skull, with a robust construction for wrangling prey.

The teeth are quite small and although there are a couple of slightly longer ones in the tooth row, they hardly count as real fangs at a paltry 3mm long. So we’re probably dealing with one of the ‘non-venomous’ colubrid snakes (many of these are actually venomous, but lack the appropriate tools to deliver that venom through human skin).

Of course, there are still well over a thousand possible species in the Colubridae – but this is where you have to start ruling out possibilities by comparing the specimen against species that are common and widespread, to begin the process of narrowing down the options.

Since this specimen is in the Museum in Ireland, Europe is a good place to start looking for likely candidates (Ireland itself being famously devoid of native snakes). There is a rather old (published in 1913), but still very useful reference called The Snakes of Europe, by G. A. Boulenger which has a section on identifying species based on their skulls.

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Fig. 6Skull of Tropidonotus natrix. (From British Museum Catalogue of Snakes). Illustration from The Snakes of Europe, by G. A. Boulenger, 1913

If you take a look through, it quickly becomes apparent that there is one species that matches the mystery object very closely – even to the position of the slightly larger teeth. It’s a species that has an interesting defense mechanism that jennifermacaire referred to:

…The closest skull I could find is from a snake that likes to roll over and play dead…

This is a fascinating behaviour seen in several snake species, but Jennifer is correct that it is seen in the species that this skull is from – the European Grass snake Natrix sp.

Of course, the story then gets more complicated again, since a couple of subspecies of Grass snake have been elevated to species in the last few years. The Iberian subspecies Natrix natrix astreptophora was recognised as N. astreptophora in 2016 and the subspecies N. n. helvetica found west of the Rhine (including in the UK) was updated to N. helvetica in 2017.

These studies were based on genetics and I’ve yet to see any way of differentiating between these species using skeletal features, so for now the best I can say about this specimen is that it’s Natrix sp. I hope you enjoyed that little slither into the world of snakes, which seems to have opened a bit of a can of worms…

 

 

Friday mystery object #372 answer

First of all, I’d like to wish you a very happy and healthy 2020!

Last year I gave you this festive-looking beetle to try your hand at identifying:

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It was a bit of a tricky one to get to species, since beetles are notorious for their huge diversity, plus they can vary in appearance quite significantly within a species.

James Bryant recognised this as a member of the Buprestidae, which is a family of wood-boring beetles that are commonly known as Jewel Beetles due to their metallic and iridescent colours. In fact, the wing cases (or elytra)  of some of the most colourful of these beetles have been used in traditional beetlewing jewellery in the parts of Asia where they are found.

Going beyond the family, the identification katedmonson provided through a great cryptic clue was spot-on (assuming I understood it properly). This particular specimen is an example of Chrysochroa rajah Gory, 1840, but in the collection it is still labelled under the synonym C. chinensis.

This species is one of those with a wide distribution, several subspecies and a variety of different colours and patterns, which can make it hard to identify based on just an image of the overall body (or habitus as it’s referred to by entomologists). Just to give you an idea of what I mean, here’s an example of the same species in the National Museum, Prague:

Chrysochroa rajah from southern China. Photo by Hectonichus 2010

Blue and green form of Chrysochroa rajah from southern China. Photo by Hectonichus 2010

So well done to katedmonson for getting this tricky identification. Look out for another mystery next week!

Friday mystery object #369 answer

Last week I gave you this weird, but rather nice object to have a go at identifying:

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Most people seemed to recognise it as the tympanic region (that’s the bony ear-related region) of a whale. But of course, I’m demanding when it comes to getting an identification and there are plenty of species of whale to rule out.

The size immediately narrowed down the possibilities – this is pretty small for a whale. But what really gives it away for the small number of people intimate with the cranial anatomy of whales (which goes beyond even my bone-nerdery), is the spongy bone attached to the tympanic bulla (that’s the bulb-shaped bit of bone that houses the inner ear).

This feature is proposed as a possible pressure receptor that’s found in the Pygmy Sperm Whale Kogia breviceps Blainville, 1838. Amazingly, Conor Ryan identified this on Twitter – his handle of @whale_nerd explains everything you need to know.

Kogia breviceps by George Brown Goode, 1887

Kogia breviceps by George Brown Goode, 1887

These toothed whales only grow to around 3.5m, which is pretty small for a whale. They share some features with their much larger Sperm Whale cousins, particularly in relation to adaptations for echolocation.

I was fortunate enough to meet Conor Ryan at the weekend at the Irish Whale and Dolphin Group conference. There were plenty of whale enthusiasts around and it was fantastic to get a chance to learn more about this incredible group of animals from a lovely bunch of passionate people.

While I was there, I also picked up some useful tips on differentiating between species of dolphin, so I may have to share those with you soon…