The reconstructed skull of Utahraptor, on display in Brigham Young University’s Museum of Paleontology. Photo by Jaren Wilkey of Brigham Young University (January 26, 2018). Creative Commons Attribution-Share Alike 4.0 International license.https://commons.wikimedia.org/wiki/File:BYU_Utahraptor_skull.jpg. The Cedar Mountain Formation is a North American geological formation which… Read More ›
fish
Leedsichthys
Leedsichthys was a very large prehistoric saltwater fish which lived during the middle and late Jurassic Period, circa 165-150 million years ago. It was named in 1889 in honor of Alfred N. Leeds who found the first specimen. Leedsichthys belonged… Read More ›
Diplurus
Diplurus was a 3 foot long freshwater coelacanth fish which lived in the northeastern United States during the late Triassic and early Jurassic Periods, approximately 220-190 million years ago. It is divided into three species: D. longicaudatus, D. newarki, and… Read More ›
Lissodus
Lissodus was a prehistoric shark which lived from the early Triassic to the middle Cretaceous Period, about 250 to 110 million years ago, give or take. Named in 1835, it was a member of a group of sharks called the… Read More ›
Polyacrodus
NOTE: This article was originally published on May 4, 2022. On December 30, 2025, it was updated and re-uploaded. Polyacrodus was a genus of prehistoric shark, composed of several species, with fossils found in North America, South America, Europe, Asia, and… 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 ›
Lepisosteus occidentalis – the Western Gar
Introduction The Hell Creek Formation of the western United States is understandably known for its dinosaur fossils, including Tyrannosaurus and Triceratops. However, in terms of sheer physical numbers, there are other species found here which surpass them by far. One… Read More ›
Semionotus
Semionotus was a genus of prehistoric fish which lived throughout the world during much of the Mesozoic Era. It was named by the famous Swiss ichthyologist and paleontologist Louis Agassiz in 1843 (type species: Semionotus bergeri). Semionotus first appeared during… Read More ›
The Big Muddy: The Mowry Sea of the Early Cretaceous Period
Today the broad expanse of the Great Plains, which forms the central part of North America, is a vast area of farms, prairies, and deserts. Here, immense herds of buffalo once roamed and wild mustangs galloped. However, the land did… Read More ›
List of Articles about the Morrison Formation
The Morrison Formation of western North America is my favorite geological / paleontological formation to study. Within these rock layers, which are dated to the late Jurassic Period from approximately 157 to 147 million years ago, are found the fossils… Read More ›