Caseosaurus is a genus

Genus

In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 of dinosaur

Dinosaur

Dinosaurs are a diverse group of animals of the clade and superorder Dinosauria. They were the dominant terrestrial vertebrates for over 160 million years, from the late Triassic period until the end of the Cretaceous , when the Cretaceous–Paleogene extinction event led to the extinction of...

 from the Late Triassic

Triassic

The Triassic is a geologic period and system that extends from about 250 to 200 Mya . As the first period of the Mesozoic Era, the Triassic follows the Permian and is followed by the Jurassic. Both the start and end of the Triassic are marked by major extinction events...

 of North America

North America

North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...

. The type species

Type species

In biological nomenclature, a type species is both a concept and a practical system which is used in the classification and nomenclature of animals and plants. The value of a "type species" lies in the fact that it makes clear what is meant by a particular genus name. A type species is the species...

, Caseosaurus crosbyensis, was formally described by Hunt, Lucas

Spencer G. Lucas

Spencer George Lucas is an American paleontologist and stratigrapher, and curator of paleontology at the New Mexico Museum of Natural History and Science. His main areas of study are late Paleozoic, Mesozoic and early Cenozoic vertebrate fossils, stratigraphy, and continental deposits,...

, Heckert, Sullivan and Lockley in 1998. It was found in the Dockum Formation of Texas

Texas

Texas is the second largest U.S. state by both area and population, and the largest state by area in the contiguous United States.The name, based on the Caddo word "Tejas" meaning "friends" or "allies", was applied by the Spanish to the Caddo themselves and to the region of their settlement in...

, in strata dating to the Late Triassic

Triassic

The Triassic is a geologic period and system that extends from about 250 to 200 Mya . As the first period of the Mesozoic Era, the Triassic follows the Permian and is followed by the Jurassic. Both the start and end of the Triassic are marked by major extinction events...

. It may, in fact, be the same dinosaur as Chindesaurus

Chindesaurus

Chindesaurus is a genus of saurischian dinosaur named after Chinde Point , near where the genoholotype specimen was discovered in the Chinle Formation of Petrified Forest National Park, Arizona, by Bryan Small in 1985...

, another early dinosaur from the same period and geological region. It has tentatively been classified as a relative of Herrerasaurus

Herrerasaurus

Herrerasaurus was one of the earliest dinosaurs. All known specimens of this carnivore have been discovered in rocks of late Ladinian age in northwestern Argentina...

.

External links

• Texas Dinosaurs from Texas A&M University
• Dinosauromorpha (includes Caseosaurus)