#doswelliids

[saritawolff]

#Archovember Day 9 - Doswellia kaltenbachi

Hailing from Late Triassic North America, Doswellia was an archosauriform relative of the crocodile-like Proterochampsids. Together with the proterochampsids, Doswelliids formed an ancient group outside of Archosauria and, unlike the Archosaurs, have no living representatives to this day.

From neck to tail, Doswellia was heavily armored in rows of bony scutes (which make it just SO fun to draw /sarcasm). Unlike crocodiles, which have a strong bite force but a much weaker ability to open their jaws, Doswellia had strong jaw muscles for both closing and opening their jaws in a scissor-like motion. It’s sharp teeth and upward-pointing eyes seem to suggest that Doswellia was at least a semi-aquatic predator. It may have hunted on land as well, partially burrowing itself with only its armoured back exposed for defense. Possible food sources include small reptiles, crustaceans, mollusks, or even large insects.

Doswellia kaltenbachi would have shared its environment with other Late Triassic North American animals, such as cynodonts, crocodyliformes, temnospondyl amphibians, Redfieldiid fish, and the freshwater shark Lissodus.

Bonus:

[saritawolff]

Archovember Day 21: Vancleavea campi

Vancleavea campi, an armored archosauriform from the Late Triassic of western North America, had a unique morphology that wildly differs from any other known basal archosauriform. It was a semi-aquatic or fully aquatic creature with a fanged, fish-like skull, short limbs, a long body, and five to six different types of osteoderms covering its body (which I’m not sure I depicted correctly; they’re very confusing.)

Most unique are the osteoderms on the tail. There is an enlogated plate on each vertebrae that together make up a paddle tail. This is very different from the tall neural spines seen on spinosaurus or other semi-aquatic archosauriforms.

The largest complete specimen found was around 3.9 feet long, though isolated pieces from other specimens suggest it could have grown larger. Vancleavea likely fed on fish, amphibians, and other aquatic prey. It is also speculated to have been an ambush predator, similar to modern day crocodilians.