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.

Resources:

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, https://theropoddatabase.blogspot.com/2010/09/kayentavenator-is-not-tetanurine.html

Mortimer, Mickey. “Is Kayentavenator a young ‘Megapnosaurus’ kayentakatae?” The Theropod Database Blog, Blogger, 1 October 2010, https://theropoddatabase.blogspot.com/2010/10/is-kayentavenator-young-megapnosaurus.html

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

“Kayentavenator.” Prehistoric wildlifehttp://www.prehistoric-wildlife.com/species/k/kayentavenator.html

“Kayentavenator.” Wikipedia, https://en.wikipedia.org/wiki/Kayentavenator

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.

Critter of the Month?

Oops! Looks like our featured critter has flown the coop! I’m terribly sorry for the delay, but Pete’s on it and will bring him back as soon as possible. 🙂

While you wait, I found a few lovely old drawings and paintings of our feathered friend. And by old, I mean a part of history. In 1941 Manfred Reichel, a Swiss paleontologist, published an article on Archaeopteryx. I love how natural and lifelike his drawings are, unlike the chimeric feathered-lizard monstrosities most people have drawn for ages.

reichel_fig09.gif.scaled1000reichel_fig8

 

Manfred Reichel took some inspiration from reading The Origin of Birds, written by Gerhard Hellmann and published in 1926. Below is one of Hellmann’s beautiful paintings.

1924 Archaeopteryx courting

 

Come back soon! Hopefully it won’t take more than a day or two to catch our feisty dancer. 😀