Leptocleidus was a genus of plesiosaur which lived in the oceans during the early Cretaceous Period about 135 to 125 million years ago. It measured just 10 feet long, which is quite small for a plesiosaur. Three species of Leptocleidus… Read More ›
reptile
Cretaceous Stegosaurs in North America? Maybe
Stegosaurus stenops. © Jason R. Abdale (August 1, 2020) Stegosaurus is one of the most famous dinosaurs in the world. With its large back plates and spiked tail, it’s commonly seen in every child’s dinosaur book and is one of… Read More ›
The Cedar Mountain Allosaur
The Cedar Mountain Formation is a geological formation located in the western United States, mostly within the state of Utah, with rocks dating to the early and middle parts of the Cretaceous Period. The Cedar Mountain Formation is most well-known… Read More ›
List of articles about the Hell Creek Formation
Since I started this blog in the Summer of 2013, I have written several articles and I have posted several examples of my artwork associated with the Hell Creek Formation. This geological formation, dated to the very end of the… Read More ›
Nedcolbertia: A North American elaphrosaur?
IntroductionNedcolbertia (named in honor of the American paleontologist Dr. Edward “Ned” Colbert, 1905-2001) was a mysterious and intriguing creature which inhabited western North America during the early Cretaceous Period about 140-130 million years ago. When it was officially named and… Read More ›
Arthropterygius
Arthropterygius, “jointed fin”, was a genus of ichthyosaur which lived in the Arctic Ocean during the Jurassic/Cretaceous transition period about 150 to 140 million years ago. Fossils of it have been found in Canada, Scandinavia, and Russia, and bones which… Read More ›
The Cedar Mountain Hypsilophodont Dinosaur
The Cedar Mountain Formation of the western United States, which is dated to the early Cretaceous Period, has produced fossils of numerous dinosaur species. Several of these are still not officially classified, and this post concerns one of them. In… Read More ›
An Ornithocheirid Pterosaur
An ornithocheirid pterosaur. © Jason R. Abdale (February 13, 2022). The “ornithocheirids” were a group of pterosaurs which dominated the skies during the early and middle parts of the Cretaceous Period from about 140 to 90 million years ago. They… Read More ›
The Sail-Backed Dinosaur from the Cedar Mountain Formation
Greetings. A few days ago, I learned of a remarkable discovery. In east-central Utah within the rock layers of the Cedar Mountain Formation, dated to the early Cretaceous Period about 135 million years ago (the same time and place where… Read More ›
Gracilisuchus
Gracilisuchus, meaning “the slender crocodile”, was a 2-foot-long reptile which lived in South America during the middle of the Triassic Period. Its remains were discovered in northwestern Argentina within the rocks of the Chañares Formation, which are dated to about… Read More ›
DINOSAURS AND BARBARIANS 