Enigmatic Triassic Hellasaur Thursday - part the fifth or so… Outcopping again

I was in fact hoping to blog about the enigmaticist hellasaur of them all, but I took an unexpected trip to the Berkeley MVZ yesterday and spent all day squinting at squamate skulls and now there is this recently deceased meter+ long water monitor thawing in the fume hood and I have this huge seastar/snail ecology dataset to analyze and we had this freak freeze that killed half of our tomato plants and…well I could go on, but I’ll spare you.

Never fear however! I’ve picked a only marginally less enigmatic hellasaur to introduce you to, one which has the decided advantage of being rather poorly known and very lightly published about.

Vancleavea osteoderm from Parker and Irmis (2005).

Vancleavea campi is largely known from isolated bony plates (osteoderms) like that shown in the picture above. A handful of partial skeletons are known, but they have yet to be fully described. Hopefully this will change soon and we’ll finally have an answer to the burning question of whether this creature was a kickass archosauriform or merely a lame old archosauromorph.

Here’s what we know about Vancleavea at present:

1. About 220 million years ago or so, it was skulking around the floodplains of Southwest Laurentia that have since become the famous Chinle Formation–stomping grounds of the infamous non-hellasaur Coelophysis and, more recently, Georgia O’Keefe.
2. Judging from the bony-plates and skeleton it probably looked kinda crocodiley, and judging from the teeth and skeleton it may have led a similar lifestyle (i.e. a semiaquatic predator).

And now to follow the grand Enigmatic Triassic Hellasaur tradition here are some pictures ganked from the Hairy Museum of Natural History showing an artist’s rather Hensenesque reconstruction of Vancleavea.

Vancleavea reconstruction by Phil Bircheff - Photo Matt Celeskey.

See you next week, I have a monitor to skin…

refs-

Parker, William G. and Randall B. Irmis 2005 “Advances in Late Triassic Paleontology based on new material from Petrified Forest National Park, Arizona” in Vertebrate Paleontology in Arizona New Mexico Museum of Natural History and Science Bulletin No. 29. Heckert, AB, and Lucas, SG, eds. [pdf]