Fossil Friday: Kayentasuchus

chibi_Kayentasuchus
Size_Kayentasuchus_flat

Species: Kayentasuchus walkeri (Kah-yen-tah-soo-kus wah-keh-rye)

What it means: Kayenta crocodile

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: Small animals, fish, or the occasional large insect. 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: I’m surrounded by big and scary dinosaurs like Dilophosaurus, Coelophysis, and Kayentavenator, so I stay out of their way. Giant Sarahsaurus (an early sauropod) and little Scutellosaurus (small armored dinosaur) are local plant eaters. Frogs, turtles, and fellow crocodile cousins stay by the river, but I don’t hang out there much. I may be related to crocs, but I like dry land better. I’ll often see a long-tailed pterosaur flying overhead for insects like beetles, dragonflies, an ancient cousin of the moth, and something called a snakefly.

Fun Facts:

  • I might look a skinny crocodile, but I’m not a crocodile at all! I’m a crocodile-ish relative called a Sphenosuchian (Ss-fee-no-soo-key-an).
  • My name comes from the place they found me, the Kayenta Formation + suchus (latin for crocodile). Suchus is a common word in the names of prehistoric crocs and croc-ish things, and comes from the word Soukhos, the ancient Greek form of the name Sobek, the Ancient Egyptian god that has the head of a crocodile. My species name, walkeri, is in memory of Alick Walker, a well known paleontologist.
LifeSize_Kayentasuchus_flat
Go ahead and put your hand up against the screen, it should be life size!

Fossil Finds: A nearly complete but fragmentary skeleton, including an incomplete skull with articulated jaw hinge (mandibular rami), articulated torso, articulated right leg, and a few other postcranial bones. Articulated means the bones fit where they should be, instead of scattered everywhere. Postcranial bones are all the bones behind the head.

Resources:

James M. Clark, Hans-Dieter Sues, Two new basal crocodylomorph archosaurs from the Lower Jurassic and the monophyly of the Sphenosuchia, Zoological Journal of the Linnean Society, Volume 136, Issue 1, September 2002, Pages 77–95, https://doi.org/10.1046/j.1096-3642.2002.00026.x

Fossil Friday: Dilophosaurus

chibi_dilo

 

Species: Dilophosaurus wetherilli (dih-lohf-oh-saw-rus weh-the-rill-eye)

What it means: Two-crested lizard

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.

Size_dilo_flat

dry floodplains_flat
During the dry season only the toughest cycads stay green

wet floodplains
During the wet season ferns and horsetails come to life

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) and Scelidosaurus (armored dinosaur) are some tough neighbors. We don’t talk much. But if I’m lucky, little Scutellosaurus (small armored dinosaur) might join me for lunch. Coelophysis (smaller meat-eater) scurry around everywhere and are 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.