This week I have a fantastic guest mystery object from Jill Sales the Museum of Life Sciences at Kings College London for you to have a go at identifying:
The skull is 98mm long and 58mm across at its widest point.
These great photos were taken by Steve Ryder, who has been working on getting an identification on this specimen. I think Steve’s thoughts on the species are right, but it’s not an easy one, so no need for cryptic clues – this is a real test of your skills, so show us what you’ve got!
Zygoma 
Baby Simba
Who’s going to try an weasel out of this one?
Carnivora, I’d imagine, to begin with.
Looks like somebody popped him in the snoot.
This is tricky since it is an immature animal. Maybe an American Badger, possibly Enhydris lutra,sea otter ,but shape of upper molars are a little off,so really need a comparative immature skull to see how much the molars change. I’m leaning toward badger.
An American Badger is the only study skull I have at home, and… I’m not sure.
—The skull I have is about 140 mm long and 80 mm across, so this one is a LOT smaller. If this is purely a result of its “immature” status, it must have been … juvenile, not sub-adult.
—Supporting the idea that it IS immature: the two little holes in the palate near the boundary between the premaxilla and the ??palatine?? are present in my Badger skull. But Paolo’s picture shows a very clear boundary suture between the two bones: in my adult specimen this boundary is invisible. (Similar remark about suture on the skull roof in Paolo’s second photo.) So a fair bit of fusion of skull bones took place between the stages represented by Paolo’s picture and my specimen.
—The rearmost cheek tooth in the denture Paolo presents looks (approximately) right to be the last lower pre-molar (so the number of premolars is right for a badger()). But there are obvious sockets behind it, so this is a specimen old enough to have gotten its adult teeth before it died.
—On the other hand, the profile (in side view) of this p4 doesn’t look QUITE right. The one in Paolo’s picture is definitely “triconodont: a highest central cusp, a somewhat lower mesial cusp, and significantly lower distal one. In the corresponding tooth in my Badger skull, the front cusp is by far the highest: behind it there is a much lower one, and behind that what I would call a small talonid.
—Mine has a (low, but distinct, and clearly visible from above) sagittal crest, meeting at the back with a crest (is this called a “nuchal” crest?) forming a rim on the upper margin of the back of the skull: these rear crests run down and curve outward (in rear view), so that their lower corners form (in top view) the rear corners of the skull. The skull in Paolo’s picture doesn’t have either of these crests. But I don’t know whether absence of these crests is a female thing, or an immature thing, or … a definitely non-badger thing.
—In the upper jaws, Paolo’s picture shows P2,P3,P4 and M1 (), but there seems to be a small hole behind M1: root of a small missing M2??? My Badger skull doesn’t have room behind the M1 for even a tiny M2. (Presence of an M2 would, I think, mean that Paolo’s is not a Mustelid, and also — contrary to Wouter’s “Baby Simba” suggestion — not a Felid.)
—But at least I think Palfreyman is right: it’s some sort of Carnivoran.
(*) I say that with some trepidation, having misidentified a premolar as a molar on the previous mystery object…
Otters seem to have less prominent sagittal, etc, crests than other mustelids, so if it IS a mustelid I’d (right now) bet on some sort of otter. The skull seems to be about the right size for a European river otter (but one photo I found seems to show a much larger ant orbital foramen than in Paolo’s picture).
But not Enhydra: Sea Otters eat molluscs, and their cheek teeth are huge, blunt cusped, hammers.
I agree with Allen on so many things , but this is a really young animal. The last molar in the mandible hasn’t erupted yet and I think the incisors could be milk teeth. That P4 is one of the things that made me question Immature Enhydra. That and the shape of the upper molars. Yes, Enhydra molars are massive crushers ,but if this was a baby, would need to see a comparative skull . I think the really straight back of the skull is more badger than sea otter. I stick with mustelid. If I can get into a museum, I can put this to rest…at least if it is from N. America.
I’m pretty sure I know what it is not, but tenuous for what it could possibly be. I’m pretty sure it is not a mustelid; they have either a huge molar or a dumbbell-shaped one behind the carnassial. The upper carnassial and adjacent molar (which seems to be permanent teeth) are pretty distinctive. The only mammal I can find with similar teeth in my limited publications and internet search is the white-tailed mongoose, Ichneumia albicauda.
I don’t like the identification because of the age of the individual and some skull morphology, but that carnassial is pretty distinctive and I couldn’t find a better match.
My earlier identification really bugged me (I really wasn’t happy about the skull morphology and kept thinking about it while working) so I went back to it after my late evening gig was over. This time I photoshopped the original photos so I could see details better and it quickly stopped looking like Ichneumia and started looking like something I immediately recognized and should have caught sooner. It is much, much younger than I originally thought and I overthought it — thinking it was from some place across the pond.
Pretty sure it is a very young Taxidea taxis, the American badger. I don’t have a very young juvenile in my bone library (I don’t have any with deciduous teeth) but I’ve seen them in archaeological contexts. I can still be wrong, but I feel much better about this than my earlier idea.
i concur with the former idea, that it’s a mustelid, just has the gestalt.
I’m going to add some thoughts here, since I’m still not certain of the identification.
This is a pretty young individual – the sutures are all unfused, the adult dentition doesn’t appear to have erupted yet, and it already measures around 10cm long. One of the larger mustelids is the Wolverine and the skull of a mature adult I’ve had on the blog before measures in at only 13cm (see https://paolov.files.wordpress.com/2015/02/mystery245b.jpg)
I think there may be a bit of underestimation of the likely size of this animal as an adult as I think there’s a lot of growing still to happen.
If that’s the case, then we can expect there to be some elongation of the muzzle and general changes in the shape of the skull associated with ontology.
I found a reference that might be helpful.
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.
This is a VERY helpful reference!
How do you access this? It asks for an institution to gain access.
I’m fortunate that the National Museum of Ireland is signed up to Jstor. Worth checking with local libraries in case they have a subscription.
Whatever this baby is, it’s fascinating to see the many skull plates, and it seems that the incisors are on a completely different plate to the canines. This may be kindergarten stuff to most of the players here, but my experience with really young skulls is nil. Thanks!
PS I think from this that even a wolverine is not quite large enough and this baby is going to get bigger than 13 cm.
I have a comment here from katedmonson – for some reason my comments aren’t working for her, so I hope others aren’t having the same problem!:
“I agree with many points with Jeanie and Allen.
I don’t think it is slender enough for a mongoose, although I do think it’s in the mustelid group.
Also, the angular process on the lower jaw is different from a mongoose. Look at the size of the infraorbital foramen – too large and triangular for a mongoose. But is the right size for a river otter or a badger.
The nares are large like a river otter’s, but the external auditory meatus is very small in river otters, and this mystery skull has larger ones.
Badger skulls have a crest along the back – unless… they are under a year old. I believe this one is that young because of the emerging adult teeth. Also the tympanic bulla seem to match for a badger. I was thinking a European badger Meles meles, but the squamosal side of the jugal in Meles meles doesn’t have the sharp point our mystery skull does. This goes back to the North American Badger, Taxidea taxis. That’s what I have so far.”
The tympanic bulla led me to mustelids. The overall shape of the skull in dorsal view looks like to one of the skunks, but the teeth morphology has nothing to do with them. The teeth look more like a gennet or a civet. I think that this specimen still have deciduous teeth, so that the shape of the dP4 could be misleading. But the M1 should be the permanent tooth. Its shape is a simple trianular one, nothing to do with badgers. And I could not find such a M1 in the reference skulls I had access to.
Alright, I was completely wrong in the dental formula. The upper carnassial is not the dP4 but the dP3. The dP4 is molariform but has nothing to do with the actual shape of the M1 … (thank you Bob Church for the bibliographic reference).
Definitely Taxidea taxus
Alright, I was completely wrong in the dental formula. The carnassial is not dP4 but dP3. dP4 has the shape of a molar but nothing to do with the actual shape of the permanent M1 (thank you Bob Church for the article).
Definitely Taxidae taxus
I’m still holding out for Taxidea taxis (and I am trying to see if I can post yet…)
And learning how to spell… duh Taxidea taxus
Also – here is a fun site you can actually view the skull in 360 degree – although it’s not a huge database, it can be helpful for general morphology.
http://skullbase.info/search.php
This was fun! A real look at good minds at work. And some great resources. Thanks a lot, gang and Paolo.