Ctenochelys
Encyclopedia
Ctenochelys is an extinct genus
of Cryptodira
, which existed during the Cretaceous
period, and lived in shallow waters. Its fossils have been found in the Ripley Formation
in central Alabama
, USA. It was first named by C.H. Sternberg in 1904, and contains four species, C. stenopora, C. acris, C. procax, and C. tenuitesta.
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 Cryptodira
Cryptodira
Cryptodira is the taxonomic suborder of Testudines that includes most living tortoises and turtles. Cryptodira differ from Pleurodira in that they lower their necks and pull the heads straight back into the shells; instead of folding their necks sideways along the body under the shells' margins...
, which existed during the Cretaceous
Cretaceous
The Cretaceous , derived from the Latin "creta" , usually abbreviated K for its German translation Kreide , is a geologic period and system from circa to million years ago. In the geologic timescale, the Cretaceous follows the Jurassic period and is followed by the Paleogene period of the...
period, and lived in shallow waters. Its fossils have been found in the Ripley Formation
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 quite consistent throughout the layer. It consists mainly of glauconitic sandstone. It was formed by sediments deposited during the...
in central Alabama
Alabama
Alabama is a state located in the southeastern region of the United States. It is bordered by Tennessee to the north, Georgia to the east, Florida and the Gulf of Mexico to the south, and Mississippi to the west. Alabama ranks 30th in total land area and ranks second in the size of its inland...
, USA. It was first named by C.H. Sternberg in 1904, and contains four species, C. stenopora, C. acris, C. procax, and C. tenuitesta.
Species
- Ctenochelys stenoporis is the type speciesType speciesIn 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...
. It was originally thought to be a species of ToxochelysToxochelysToxochelys is an extinct genus of sea turtle from the Cretaceous period. It is the most commonly found fossilized turtle species in the Smoky Hill Chalk, in western Kansas. Toxochelys was about 2 m in length...
; T. bauri, until Sternberg declared it a separate genus. The two genera are similar in carapaceCarapaceA carapace is a dorsal 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 tortoises, the underside is called the plastron.-Crustaceans:In crustaceans, the...
s. - Ctenochelys acris was first named by Zangerl in 1953.