Podocnemididae is a family of pleurodire (side-necked) turtles, once widely distributed. Most of its 20 genera and 30 species are now extinct. Seven of its eight surviving species are native to South America: the genus Peltocephalus, with only one species ; and the genus Podocnemis, with six living species of South American side-necked river turtles. There is also one genus native to Madagascar: Erymnochelys, the Madagascan big-headed turtle, whose single species E. madagascariensis.
The Arrau turtle, also known as the South American river turtle, giant South American turtle, giant Amazon River turtle, Arrau sideneck turtle, Amazon River turtle or simply the Arrau, is the largest of the side-neck turtles (Pleurodira) and the largest freshwater turtle in Latin America. The species primarily feeds on plant material and typically nests in large groups on beaches. Due to hunting of adults, collecting of their eggs, pollution, habitat loss, and dams, the Arrau turtle is seriously threatened.
Podocnemis is a genus of aquatic turtles, commonly known as South American river turtles, in the family Podocnemididae. The genus consists of six extant species occurring in tropical South America. Three additional species are known only from fossils.
The Pleurodira are one of the two living suborders of turtles, the other being the Cryptodira. The division between these two suborders represents a very deep evolutionary divide between two very different types of turtles. The physical differences between them, although anatomical and largely internal, are nonetheless significant, and the zoogeographic implications of them are substantial. The Pleurodira are known more commonly as the side-necked turtles and the name Pleurodira quite literally translates to side neck, whereas the Cryptodira are known as hidden-necked turtles. The Pleurodira turtles are currently restricted to freshwater habitats in the Southern Hemisphere, largely to Australia, South America, and Africa. Within the Pleurodira, three living families are represented: Chelidae, also known as the Austro-South American side-necked turtles, the Pelomedusidae, also known as the African mud terrapins, and the Podocnemididae, also known as the American side-neck river turtles. However, they were cosmopolitan clade during the Cretaceous and most of the Cenozoic, and even occurred in marine environments around the world.
Hydromedusa is a turtle genus in the family Chelidae, commonly known as the South American snake-necked turtles. They are quite closely related to the South American side-necked swamp turtles (Acanthochelys) and the snake-necked turtles of the Australian-Melanesian region (Chelodina), but less closely to the spine-necked river turtles of South America (Podocnemididae) which belong to a more modern lineage of Pleurodira.
Bothremydidae is an extinct family of side-necked turtles (Pleurodira) known from the Cretaceous and Cenozoic. They are closely related to Podocnemididae, and are amongst the most widely distributed pleurodire groups, with their fossils having been found in Africa, India, the Middle East, Europe, North America and South America. Bothremydids were aquatic turtles with a high morphological diversity, indicative of generalist, molluscivorous, piscivorous and possibly herbivorous grazing diets, with some probably capable of suction feeding. Unlike modern pleurodires, which are exclusively freshwater, bothremydids inhabited freshwater, marine and coastal environments. Their marine habits allowed bothremydids to disperse across oceanic barriers into Europe and North America during the early Late Cretaceous (Cenomanian). The youngest records of the group are indeterminate remains from Saudi Arabia and Oman, dating to the Miocene.
Caririemys is an extinct genus of side-necked turtles, belonging to the Pelomedusoides of the family Euraxemydidae. The type species is C. violetae. A single fossil of an individual was found in the Santana Formation in Brazil, an 80-million-year-old Late Cretaceous deposit that has so far preserved other fossil reptiles such as dinosaurs and crocodilians.
Cearachelys is an extinct genus of pleurodiran turtle which existed some 110 million years ago. The genus is monotypic, with only type species Cearachelys placidoi known.
The Bauru Group is a geological group of the Bauru Sub-basin, Paraná Basin in Minas Gerais, São Paulo, General Salgado, Itapecuru-Mirim, Mato Grosso, Brazil whose strata date back to the Late Cretaceous. Dinosaur remains are among the fossils that have been recovered from the formation.
Eugene S. Gaffney is an American paleontologist and leading authority on the morphology and evolutionary history of turtles.
Brontochelys is an extinct genus of podocnemidid from the Miocene of Pakistan. The only species known, B. gaffneyi was classified before in the genus Shweboemys, which is known from the Pliocene of Burma. Brontochelys is represented only by its type specimen BMNH R.8570, a nearly complete skull, which exact locality is unknown but probably comes from the Lower Miocene sediments in the Bugti Hills, in Baluchistan, Pakistan. This skull is different from its relatives like Shweboemys, Lemurchelys and Stereogenys by its large, forward-faced orbits, a large frontal bone that composes most of the dorsal orbit margin and a palatal curved. The name of Brontochelys is formed by the Greek words bronte, "thunder" and chelys, "turtle", in reference to the large size of the skull.
Araripemydidae is a family of freshwater aquatic turtles belonging to the order Pleurodira, known from the Early Cretaceous of South America and Africa. The family contains two recognised monotypic genera, Araripemys and Taquetochelys, from the Santana Group of Brazil and the Elrhaz Formation of Niger, respectively, which date to the Aptian-Albian stages of the Early Cretaceous. They are consider to be the most basal lineage within the Pelomedusoides. They are thought to have been specialised suction feeders. Laganemys was named in 2013 but was later determined to be synonymous with Taquetochelys.
Bauruemys is an extinct genus of turtles in the family Podocnemididae.
Thanos is a genus of carnivorous brachyrostran abelisaurid dinosaur that lived in Brazil during the Santonian stage of the late Cretaceous Period. It contains only a single species known as T. simonattoi.
Rosasia is an extinct genus of bothremydid pleurodiran turtle that was discovered in the Argilas de Aveiro Formation of Portugal. The genus consists of a single species, R. soutoi, named after Alberto Souto.
Arenila is an extinct genus of bothremydid pleurodiran turtle that was discovered in the Western Desert of Egypt. The genus consists solely of type species A. krebsi.
Azabbaremys is an extinct genus of bothremydid pleurodiran turtle that was discovered in the Teberemt Formation of Mali. It was described in 2001, based on a skull that had been recovered in an expedition in 1981. The genus consists solely of the type species Azabbaremys moragjonesi. The genus name is derived from Azabbar, a monster in Tamasheq folk stories. The species is named for Morag Jones, a research student who participated in the discovery of the specimen and died in the expedition. Azabbaremys is most closely related to another Paleocene side-necked turtle, Acleistochelys.
Eotaphrosphys is an extinct genus of bothremydid pleurodiran turtle that was discovered in the Mont Aime Formation, France. Originally assigned to the genus "Tretosternum", it consists exclusively of type species E. ambiguum.
Caninemys is an extinct genus of large freshwater side-necked turtle, belonging to the family Podocnemididae. Its fossils have been found in Brazil and Colombia, in rocks dating back from the middle to late Miocene.
Ibirania is a genus of dwarf saltasaurine titanosaur dinosaur from the Late Cretaceous São José do Rio Preto Formation of south-east Brazil. The type species is Ibirania parva. It is one of the smallest sauropods known to date, comparable in size to the titanosaur Magyarosaurus.
