''Ctenochelys'' is an

extinct Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

of marine turtle (

Cryptodira The Cryptodira ('' el, hidden neck'') are a suborder of Testudines that includes most living tortoises and turtles. Cryptodira differ from Pleurodira (side-necked turtles) in that they lower their necks and pull the heads straight back into the ...

Pancheloniidae Pancheloniidae is a clade of sea turtles It is defined as all turtles more closely related to cheloniid sea turtles than to dermochelyid ("leatherback") sea turtles.Joyce W.G, Parham J.F, Gauthier J.A. Developing a protocol for the conversion of ...

), which existed during the

Cretaceous The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of th ...

period, and lived in the shallow waters of the

Western Interior Seaway The Western Interior Seaway (also called the Cretaceous Seaway, the Niobraran Sea, the North American Inland Sea, and the Western Interior Sea) was a large inland sea that split the continent of North America into two landmasses. The ancient sea, ...

. Its fossils have been found in the

Ripley Formation The Ripley Formation is a geological formation in North America found in the U.S. states of Alabama, Georgia, Mississippi, Missouri, and Tennessee. The lithology is consistent throughout the layer. It consists mainly of glauconitic sandstone. It ...

and

Mooreville Chalk The Mooreville Chalk is a geological formation in North America, within the U.S. states of Alabama and Mississippi, which were part of the subcontinent of Appalachia. The strata date back to the early Santonian to the early Campanian stage of ...

of central

Alabama (We dare defend our rights) , anthem = "Alabama (state song), Alabama" , image_map = Alabama in United States.svg , seat = Montgomery, Alabama, Montgomery , LargestCity = Huntsville, Alabama, Huntsville , LargestCounty = Baldwin County, Al ...

, United States. It was first named by C.H. Sternberg in 1904, and contains two species, ''C. stenoporus'' and ''C. acris''.

Species

*''Ctenochelys stenoporus'' is the

type species In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specimen ...

. It was originally thought to be a species of ''

Toxochelys ''Toxochelys'' () is an extinct genus of marine turtle from the Late Cretaceous period. It is the most commonly found fossilized turtle species in the Smoky Hill Chalk, in western Kansas. Description ''Toxochelys'' was about 2 m (6 ft ...

''; ''T. bauri'', until Sternberg declared it a separate genus. The two genera are similar in

carapace A carapace is a Dorsum (biology), dorsal (upper) section of the exoskeleton or shell in a number of animal groups, including arthropods, such as crustaceans and arachnids, as well as vertebrates, such as turtles and tortoises. In turtles and tor ...

s. *''Ctenochelys acris'' was first named by Zangerl in 1953 and is now thought to be one of the earliest ancestors of modern

cheloniid Cheloniidae is a family of typically large marine turtles that are characterised by their common traits such as, having a flat streamlined wide and rounded shell and almost paddle-like flippers for their forelimbs. They are the only sea turtles t ...

References

External links

Paleobiology DatabaseSt. Catherine's Island Sea Turtle Conservation Program: Life History: Geologic History of Sea Turtleswww.paleofile.com - Alphabetical list, Section C
Late Cretaceous turtles of North America Cryptodira Prehistoric turtle genera Extinct turtles {{paleo-turtle-stub