Saturday, November 23, 2013


Here's my rendition of the new Hell Creek velociraptorine dromaeosaur. It's known only from the maxilla and dentary, so I decided to only draw the business end of the animal (that, and I didn't really have the time for a full reconstruction). It's depicted staring at a hispine beetle, of which there is abundance evidence (Johnson et al 2000) from Hell Creek ichnofossils.

The animal has been known from teeth for many years, and was only recently finally given a name, Acheroraptor temertyorum, after the underworld Acheron of Greek mythology (Hell Creek reference and so on). Phylogenetic analysis recovers it as a velociraptorine, the most basal member of the group containing Velociraptor, Adasaurus and Tsaagan.

I had a bit of consternation on whether or not to depict the animal with lips: the original version lacked full lips, and I drew the upper teeth overlapping the dentary. Ultimately I decided to add lips and the result is the above image. The original can be seen to the right.

Evidence for lips on theropods is still debated, but it seems to be mounting over time. I've been wishy-washy about lips: my preferred state of depicting dromaeosaurs, at least, was with a sort of "in-betweenish" lip situation, where lips covered around half the vertical distance of the upper teeth, but the upper teeth still overlapped the dentary somewhat. Jaime Headden has a great post on the complexities of dinosaur lips and why some options aren't really satisfactory without more information.

Photoshop CS4, ~2-3 hours