The Chelydridae is a family of turtles that has seven extinct and two extant genera. The extant genera are the snapping turtles, Chelydra and Macrochelys. Both are endemic to the Western Hemisphere. The extinct genera are Acherontemys, Chelydrops, Chelydropsis, Emarginachelys, Macrocephalochelys, Planiplastron, and Protochelydra.
Dissorophidae is an extinct family of medium-sized, temnospondyl amphibians that flourished during the late Carboniferous and early Permian periods. The clade is known almost exclusively from North America.
Araeoscelidia or Araeoscelida is a clade of extinct diapsid reptiles superficially resembling lizards, extending from the Late Carboniferous to the Early Permian. The group contains the genera Araeoscelis, Petrolacosaurus, the possibly aquatic Spinoaequalis, and less well-known genera such as Kadaliosaurus and Zarcasaurus. This clade is usually considered to be the sister group to all later diapsids.
Megacerops is an extinct genus of the prehistoric odd-toed ungulate family Brontotheriidae, an extinct group of rhinoceros-like browsers related to horses. It was endemic to North America during the Late Eocene epoch, existing for approximately 4.1 million years.
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.
Emarginachelys cretacea is a turtle belonging to the group Cryptodira, known from well preserved fossils from the Maastrichtian stage of the Late Cretaceous of Montana. Its exact phylogenetic position within Cryptodira is uncertain; different authors considered it to be either the earliest described chelydrid or a fossil relative of kinosternoids.
Planiplastron is an extinct genus of snapping turtle. It was first described by Chkhikvadze in 1971. It was assigned to the family Chelydridae by R. L. Carroll in 1988.
Testudinata is the group of all tetrapods with a true turtle shell. It includes both modern turtles (Testudines) and many of their extinct, shelled relatives (stem-turtles), though excluding Odontochelys and Eorhynchochelys, which are placed in the more inclusive Pantestudines.
Procolophonoidea is an extinct superfamily of procolophonian parareptiles. Members were characteristically small, stocky, and lizard-like in appearance. Fossils have been found worldwide from many continents including Antarctica. The first members appeared during the Late Permian in the Karoo Basin of South Africa.
Kurmademys is an extinct genus of side-necked turtle which existed in India during the late Cretaceous period. It was first named in 2001, by Eugene S. Gaffney, Sankar Chatterjee, and Dhiraj K. Rudra, and contains the species Kurmademys kallamedensis. The species name is derived from the Kallamedu Formation of southern India, where the type specimen of the genus was discovered. It was assigned to the family Bothremydidae.
Cedrobaena is an extinct genus of turtle which existed in the Tiffanian Cedar Point Quarry, Wyoming and in the latest Maastrichtian Hell Creek Formation, United States. It was first named by Tyler R. Lyson and Walter G. Joyce in 2009 and the type species is Cedrobaena putorius.
Eugene S. Gaffney is an American paleontologist and leading authority on the morphology and evolutionary history of turtles.
Baenidae is an extinct family of paracryptodiran turtles known from the Early Cretaceous to Eocene of North America. While during the Early Cretaceous they are found across North America, during the Late Cretaceous they are only found in Laramidia, having disappeared from Appalachia. The majority of lineages survived the K-Pg Extinction, but the family was extinct by the latest Eocene. The name of the type genus, Baena, appears to be of Native American origin. They are primarily found in freshwater deposits, and are considered to be aquatic, with a largely generalist habit.
Anna Katherine "Kay" Behrensmeyer is an American taphonomist and paleoecologist. She is a pioneer in the study of the fossil records of terrestrial ecosystems and engages in geological and paleontological field research into the ecological context of human evolution in East Africa. She is Curator of Vertebrate Paleontology in the Department of Paleobiology at the Smithsonian Institution's National Museum of Natural History (NMNH). At the museum, she is co-director of the Evolution of Terrestrial Ecosystems program and an associate of the Human Origins Program.
The New Egypt Formation is a Late Cretaceous (Maastrichtian) geologic formation of the Monmouth Group in New Jersey, United States.
The Chandler Bridge Formation is a geologic formation in South Carolina. It preserves fossils dating back to the Chattian of the Paleogene period, corresponding to the Arikareean in the NALMA classification. The formation overlies the Ashley Formation and is overlain by the Edisto Formation.
The Washakie Formation is a geologic formation in northern Colorado and southern Wyoming. It preserves many mammal, bird, reptile and other fossils dating back to the Lutetian stage of the Eocene within the Paleogene period. The sediments fall in the Bridgerian and Uintan stages of the NALMA classification.
Americhelydia is a clade of turtles that consists of sea turtles, snapping turtles, the Central American river turtle and mud turtles, supported by several lines of molecular work. Prior to these studies some morphological and developmental work have considered sea turtles to be basal members of Cryptodira and kinosternids related to the trionychians in the clade Trionychoidea. Americhelydia and Testudinoidea, both clades within Durocryptodira, split a part during the early Cretaceous.
The Globidensini or Globidentatini are a tribe of mosasaurine mosasaurs, a diverse group of Late Cretaceous marine squamates. Members of the tribe, known as "globidensins" or "globidensine mosasaurs", have been recovered from North America, Europe, Africa and Asia. The tribe contains the genera Globidens, Carinodens, Igdamanosaurus, Harranasaurus and Xenodens. Features of the maxilla and digits make the placement of Carinodens and Xenodens in the tribe uncertain; some researchers have suggested that they may be more appropriately placed in the Mosasaurini.
Araiochelys is an extinct genus of bothremydid pleurodiran turtle that was discovered in the Ouled Abdoun Basin, Morocco. The genus consists solely of type species A. hirayamai.
