Friday mystery object #443 answer

Last week I gave you this cute little fuzzball to have a go at identifying:

Everyone spotted that this is one of the New World porcupines (AKA the Erethizontidae), but there are 18 species to choose from. Some have quite short hairs between their quills, giving a spiky appearance, but this specimen has definite floof. The tail is quite short and the body is small – as several people noticed in the comments.

With a relatively small number of species, and with a few distinctive features to look for, you might expect that scanning through images of the various different species could help get an identification. It turns out that this method worked a bit too well, since this very specimen happens to be used for the image used to depict the species on Wikipedia – as spotted by Allen Hazen.

This mystery object is a Brown Hairy Dwarf Porcupine Coendou vestitus, Thomas, 1899. The reason our specimen has been used to depict the species is probably because there are very few other images of this animal dead or alive – which suggests that it’s probably rather rare (apparently nobody recorded seeing one for over 75 years).

This specimen has a few question marks for me – in particular the collection locality, which is listed as Chiriqui, Central America. This doesn’t sound right, considering the species is considered endemic to the Eastern Cordillera in the Colombian Andes – over 1,000km away. It’s probably down to a data mix up, but if not, it raises some interesting questions.

Friday mystery object #429 answer

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

It turned out to be easier than I suspected, because an image of this specimen just so happens to be used on the Wikipedia page for the species. This was a bit of a give-away for anyone who even got close to the type of animal this is. So let’s figure out what general type of animal we are dealing with.

First of all, it’s fairly clearly a rodent when you look at those incisors. I suppose incisors like that could be found in one of the lagomorphs (rabbits, hares and pikas) but they all have much larger ears in relation to their bodies (even the relatively shorter eared pikas have much bigger ears than the mystery specimen).

There are a lot of rodents, but this one is quite large, which helps narrow things down. The majority of large rodents are either semiaquatic (like Capybara, Beaver and Coypu – and it’s not one of them) or spiky (a variety of unrelated porcupines from the Old and New Worlds). Then there are the maras, agoutis, and pacas (plus relatives), but they all tend to have almost absent tails and quite long legs compared to the mystery object.

There is another group that has some moderately large members though – the hutias. There are 10 species living on various Caribbean Islands, with a relatively wide variety of adaptations thanks to island effects. In particular their tails vary from being almost absent to being quite long, thick and prehensile. Checking tails should pretty much seal the identification. Of course, it’s much easier to spot when there’s a photo of the same specimen, on it’s quite distinctive base, with a label:

Image by Illustratedjc, 2015

So well done to everyone who figured this out that this is the Bahamian Hutia Geocapromys ingrahami (J.A. Allen, 1891), especially if you didn’t spot the Wikipedia entry!