Friday mystery object #234 answer

Last Friday I gave you this mystery skull to identify, which I discovered in a box of unidentified bits and bobs:

mystery234

It was pretty obvious that it was the skull of a big cat of some kind, with most of you suggesting a Jaguar or Cheetah (either of which would make me very happy as we have the skull of neither in the Horniman collection). Unfortunately it appears to belong to neither.

As I’ve mentioned  before, cats are quite difficult to differentiate from each other as they haven’t been diverging for all that long and their widespread distributions can mean that populations within a particular species can be quite variable in morphology. Leopards are a good example of this, with a (once continuous) range from Korea to South Africa.

Global distribution of the leopard (Panthera pardus) by Tommyknocker

Global distribution of the leopard (Panthera pardus) by Tommyknocker

As it turns out, this specimen is most likely from a Leopard Panthera pardus (Linnaeus, 1758), since it’s from an adult animal (as is clear from the well formed sagittal crest) but is on the small side for a Lion or Tiger and too big for a Cougar or Cheetah. It also lacks the broad post orbital region seen in the Cheetah and Snow Leopard, and it lacks the concave profile of both the Snow Leopard and Jaguar. All of these identification pointers can be found in this handy pdf by Margaret “Cookie” Sims.

Just to show you what I mean about the variability within a species, here’s a second skull from the same box, that also matches the Leopard identification.

Leopards

I expect the big difference in size is largely down to sexual dimorphism, but as you can see the overall proportions are quite different as well. This may be a difference between widely separated populations, or it could just be individual variation – either way it goes to show that cats are hard to identify.

Friday mystery object #225 answer

Last Friday I gave you this felid skull to identify:

mystery225

As with the other cats over the last few weeks, it’s been difficult to find really clear diagnostic features.

The size helps narrow down the possibilities and the lack of divided auditory bullae rules out some of the species of Lynx, as does the presence of the small first premolar.

However, beyond that there isn’t much to really differentiate this cat from other species, apart from general features of relative proportion (height vs width vs length) and perhaps the angle of the rear part of the sagittal crest (which will probably vary between individuals).

Nonetheless, henstridgesj managed to correctly identify this as an Ocelot Leopardus pardalis (Linnaeus, 1758), one of the largest of the small cats in South America.

Ocelot, 2003 from US Fish & Wildlife Service, Image Archive

My challenge is going to be find a way to pull together the variety of cat skulls we’ve had for the last few weeks, to help make cat skulls a little easier to identify in the future – if that’s even possible. No pressure…

Friday mystery object #224 answer

Last Friday I gave you this felid skull to have a go at identifying:

mystery224

The size was larger than the previous cat skulls I’ve shown you, which helped reduce the possibilities a bit – after all, there are more smaller cats than bigger ones.

As it turns out, Sam Misan and henstridgesj both managed to work out that this is the skull of a Serval Leptailurus serval (Schreber, 1776).

A Serval cat at Serengeti National Park, Tanzania, by Bob, 2007

A Serval cat at Serengeti National Park, Tanzania, by Bob, 2007

These long-legged cats have a relatively small head, but huge ears – and the large external auditory meatus (ear hole) with a very pronounced ridge above for attachment of the muscles of the pinna (the fleshy part of the ear) helps reflect that.

The long legs and the big ears are key to the Serval’s hunting technique in the long grasses of the African savannah, where they listen for the movement of rodents which they dramatically leap on. Probably easier to appreciate this method by seeing it:

Friday mystery object #224

For the last few weeks I’ve been using cat skulls as mystery objects, because they are really hard to tell apart and I was hoping that some useful distinguishing features might get spotted when you try to identify them.

I certainly feel like I’ve learned something, but I’m pleased to say that there aren’t too many more skulls to go, because it’s really difficult. This next one should hopefully be a bit easier than some of the recent cats:

mystery224

Any idea what fine felid this skull comes from?

As usual I would really appreciate your thoughts in the comments section below – let’s see if we can crack this!

Friday mystery object #222 answer

Last Friday I gave you this fabulous feline skull to have a go at identifying:

mystery222

No one got quite the right species, but several people (Crispin, manwhohunts, Maxine and Alex Klein) managed to narrow it down to the correct genus.

The flat frontals give the forehead a slope rather than the usual curve we’ve seen in previous cats of this size, making the cranium appear very domed in contrast. The post orbital processes are quite short and gracile (slender). The jaw is quite short while maxilla bone above the canines appears pinched in and the nasals are steep and protruding somewhat.  These are features that appear in the genus Leopardus – the South and Central American small spotted cats.

How to distinguish between different species of Leopadus is more of a problem. Daniel Jones picked up on the incredibly robust bone margin of the foramen magnum (the hole the spinal chord goes into), which may be distinctive, but so far I’ve not seen the underside of other small Leopardus species skulls, so I can’t be sure.

All I know is that this is the skull of an Oncilla Leopardus tigrinus (Schreber, 1775), a small and mainly ground-hunting South American forest cat. I’ve said it before and I’ll say it again, cats are so difficult to identify!