#silesaur

DINOVEMBER 1/13: Gondwanax paraisensis

Hello everyone! I'm doing Dinovember again this year, but a little differently. I'll only be doing 3 drawings a week (ish) in order to pace myself, as in past years going the full 30 hasn't worked for me. As per usual, I'll be following my own list which is sorted oldest-youngest, with the focus this year being on new discoveries.

Talking of new discoveries, Gondwanax was only described in September this year from a femur (and other potentially assignable scraps) found in Brazil's Santa Maria formation. Gondwanax was one of the oldest known dinosauromorphs at 240Ma-230Ma, rivalling animals like Nyasasaurus, the closely related Asilisaurus from Tanzania and furthering our knowledge of the origins of dinosauria.

Ischigualasto Formation Poster

A stylized depiction of a scene from Late Triassic Argentina, around 230 million years ago. Ischigualasto was home to a varied assortment of vertebrates, including therapsids, pseudosuchians and some of the very first dinosaurs.

252mya.com/triassicargentina

New Proto-Dinosaur Found in Colorado

A lanky reptile found in the Centennial State is a close cousin of early dinosaurs

What’s almost a dinosaur, but not quite? The answer, as paleontologists have come to understand, is “a silesaur!”, a non-dinosaurian dinosauromorph. I know that’s a bit of a mouthful. Let’s unpack that.

Silesaurs aren’t exactly famous in fossil circles yet. The iconic member of the group, Silesaurus, was named in 2003 and the group’s identity wasn’t fully recognized until 2010. As old as they are, dating back through the Middle and Late parts of the Triassic, they’re pretty new on the Mesozoic block. And they’re important to our understanding of how dinosaurs evolved. Silesaurs are not technically dinosaurs, but they’re close relatives that belong to the larger group which dinosaurs are nested in.

That’s why they’re called non-dinosaurian dinosauromorphs – in short, protodinos. And paleontologists Jeffrey Martz and Bryan Small have just named a new one from Colorado.

The new silesaur, known from parts of the skull and body, is named Kwanasaurus williamparkeri and lived more than 207 million years ago. Its name is a combination of Ute and Greek meaning “eagle lizard,” while the species name honors influential Triassic paleontologist Bill Parker. It’s the fourth silesaur known from North America, and the latest of 11 described so far...