Fossil Friday: Kayentavenator

Species: Kayentavenator Elysiae (Kah-yen-tah-veh-nay-ter Eh-lee-see-eye)

What it means: Kayenta hunter

Other species: none

Where I live: Arizona in the U.S.A.- The Kayenta formation

When to find me: The Early Jurassic period, about 196 million years ago.

My favorite food: Meat! I’m a carnivore.

My neighborhood: The Kayenta formation used to be a tropical floodplain, a bit like African savannah today- but no grass or flowers. Ferns cover the open plains, dotted with islands of spiky cycad groves. Rivers crisscross the land with lush tree ferns, ginkgo trees, and conifers. Every year during the wet season the plains turn into a flooded marsh, but the hottest months bring no rain, and the rivers shrink until the plains are almost as dry as the great desert that lies to the north.

A few of my neighbors: Sarahsaurus (an early sauropod) is a tough neighbor. We don’t talk much. But if I’m lucky, little Scutellosaurus (small armored dinosaur) might join me for lunch. Dilophosaurus is the biggest carnivore around, but Coelophysis (smaller meat-eater) is happy to take a few leftovers or join me on a quick chase after frogs, turtles, or a crocodile cousin or two. They like to stay close to the rivers. A long-tailed pterosaur patrols the skies for insects like beetles, dragonflies, an ancient cousin of the moth, and something called a snakefly.

Fun Facts: 

  • Paleontologists don’t really know how big I could grow, because the only fossils found are of a juvenile, with a lot of growing left to do!
  • There’s been a bit of discussion back and forth about what family I should be in. I was first described as a Tetanuran, which is a group that includes dinosaurs like Tyrannosaurus rex, Allosaurus, Ornithomimus, and even birds, just to name a few. Others suggested I was related to the local Coelophysis k. or possibly a young Dilophosaurus, but the Dilophosaurus idea was quickly ruled out since other fossils of young Dilophosaurus have been found, and mine don’t look exactly like them. All in all there are not very many bones to go on, and it can be difficult to figure out where the puzzle pieces go when they are broken and squashed with time!
  • A lot of dinosaurs are named after the place they’re found, like me! Kayenta + venator (latin for hunter). Hunter of the Kayenta Formation.

Fossil Finds:

Only one partial, juvenile skeleton with part of the pelvis, some vertebrae, and pieces of hind legs.


Gay, Robert. 2010. “Kayentavenator elysiae“, a new tetanuran from the early Jurassic of Arizona” In: Notes on Early Mesozoic Theropods. Lulu Press. p. 27-43. ISBN 978-0-557-46616-0

Mortimer, Mickey. “Kayentavenator is not a tetanurine.” The Theropod Database Blog, Blogger, 30 September 2010,

Mortimer, Mickey. “Is Kayentavenator a young ‘Megapnosaurus’ kayentakatae?” The Theropod Database Blog, Blogger, 1 October 2010,

These two websites were a huge help in knowing where to start when finding research material and basic information.

“Kayentavenator.” Prehistoric wildlife

“Kayentavenator.” Wikipedia,