|
Podocnemididae
Podocnemididae is a family of pleurodire (side-necked) turtles, once widely distributed. Most of its 41 genera and 57 species are now extinct. Seven of its eight surviving species are native to South America: the genus '' Peltocephalus'', with two species, only one of which is extant (''P. dumerilianus'', the Big-headed Amazon River turtle); and the genus ''Podocnemis'', with six living species of South American side-necked river turtles and four extinct. There is also one genus native to Madagascar: '' Erymnochelys'', the Madagascan big-headed turtle, whose single species ''E. madagascariensis''. Like other pleurodire turtles, podocs have a "side-necked" defensive posture, turning the head sideways to hide it under the shell. Another characteristic of pleurodires is that the pelvis is fused to the shell which prevents pelvic motion, making it difficult to walk on land. Podocnemididae turtles live in aquatic environments and have shells streamlined to aid in swimming. The family ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Big-headed Amazon River Turtle
The Big-headed Amazon River turtle (''Peltocephalus dumerilianus''),"''Peltocephalus dumerilianus'' " The Reptile Database. also known as the big-headed sideneck, is a species of turtle in the Family (biology), family Podocnemididae. Taxonomy 
An additional, much larger species of ''Peltocephalus'' is known, the extinct ''Peltocephalus maturin''.
''Peltocephalus'' is the most basal podocnemidid genus, splitting off in the Cretaceous around 86 million years ago.< ...
[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Madagascan Big-headed Turtle
The Madagascan big-headed turtle (''Erymnochelys madagascariensis'') is a turtle native to the waters of permanent slow moving rivers and lakes in western Madagascar. These turtles are critically endangered and have been evaluated to be the most endangered turtle in the world by a 2018 review. Due to its ancient origins and threatened status, it is ranked as #1 on the EDGE of Existence programme's list of priority reptiles. Taxonomy It is a highly evolutionary distinctive species, the only member of the ancient family Podocnemidae found outside of South America. It diverged from its closest living relative, ''Podocnemis'', during the Late Cretaceous, about 78 million years ago. Fossils of podocnemid turtles that are suggested to be closely related to ''Erymnochelys'' belonging to the same tribe Erymnochelyini, are known from the Cenozoic of Africa and Europe, with the youngest remains of turtles belonging to Erymnochelyini in mainland Africa dating to the Pliocene. Descriptio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stupendemys
''Stupendemys'' is an extinct genus of freshwater side-necked turtle, belonging to the family Podocnemididae. It is the largest freshwater turtle known to have existed, with a carapace over 2 meters long. Its fossils have been found in northern South America, in rocks dating from the Middle Miocene to the very start of the Pliocene, about 13 to 5 million years ago. Male specimens are known to have possessed bony horns growing from the front edges of the shell and the discovery of the fossil of a young adult shows that the carapace of these turtles flattens with age. A fossil skull described in 2021 indicates that ''Stupendemys'' was a generalist feeder. History and naming ''Stupendemys'' was first named in 1976 by Roger C. Wood based on specimen MCNC-244, the medial portion of a large sized carapace with associated left femur, scapulacoracoid and a cervical vertebra. Wood also described several other specimens he referred to ''Stupendemys'', which includes MCZ(P)-4376. This sp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peltocephalus Maturin
''Peltocephalus maturin'' is an extinct species of podocnemidid river turtle closely related to the big-headed Amazon River turtle (''Peltocephalus dumerilianus'') that lived during the Late Pleistocene and Early Holocene in what is now Brazil. ''P. maturin'' is known from a singular lower jaw of enormous size, with estimates suggesting its carapace may have reached lengths of around . This would make it one of the largest freshwater turtles in history, comparable in size to the Paleocene podocnemidid '' Carbonemys'' and only exceeded by the Miocene podocnemidid ''Stupendemys''. Like its closest relative, it was likely an omnivore, the narrow cutting surface of its lower jaw unsuited for strict herbivory or durophagy. History and naming ''Peltocephalus maturin'' was described in 2024 on the basis of specimen MERO.PV.H 007, a partial lower jaw discovered by gold miners within the Taquaras Quarry of Rondônia, Brazil. Since the Rio Madeira Formation is the only geological unit expo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pelomedusidae
:''Alternatively, "Pelomedusidae" may refer to the Pelomedusoidea. See below for details.'' Pelomedusidae is a family of freshwater turtles endemic to sub-Saharan Africa, including Madagascar, São Tomé, and the Seychelles (although this population may have been introduced by humans). They range in size from in carapace length, and are generally roundish in shape. They are unable to fully withdraw their heads into their shells, instead drawing them to the side and folding them beneath the upper edge of their shells, hence are called African side-necked turtles. The family contains two living genera, '' Pelomedusa'' and '' Pelusios''. They are distinguished from their closest relatives by a hinge in the front section of the plastron.Obst, Fritz Jürgen (1998): elomedusinae ''In:'' Cogger, H.G., & Zweifel, R.G. (eds.): ''Encyclopedia of Reptiles and Amphibians'': 112-113. San Diego: Academic Press. . Pelomedusids spends most of their time in the mud at the bottom of rivers or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Turtle
Turtles are reptiles of the order (biology), order Testudines, characterized by a special turtle shell, shell developed mainly from their ribs. Modern turtles are divided into two major groups, the Pleurodira (side necked turtles) and Cryptodira (hidden necked turtles), which differ in the way the head retracts. There are 360 living and recently extinct species of turtles, including land-dwelling tortoises and freshwater terrapins. They are found on most continents, some islands and, in the case of sea turtles, much of the ocean. Like other Amniote, amniotes (reptiles, birds, and mammals) they breathe air and do not lay eggs underwater, although many species live in or around water. Turtle shells are made mostly of bone; the upper part is the domed Turtle shell#Carapace, carapace, while the underside is the flatter plastron or belly-plate. Its outer surface is covered in scale (anatomy), scales made of keratin, the material of hair, horns, and claws. The carapace bones deve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pleurodira
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 rive ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Podocnemis
''Podocnemis'' is a genus of aquatic turtles, commonly known as South American river turtles, in the Family (biology), family Podocnemididae. The genus consists of six Extant taxon, extant species occurring in tropical South America.''Podocnemis'' The Reptile Database. www.reptile-database.org. Four additional species are known only from fossils. These turtles have pig-like noses but are not closely related to the pig-nosed turtle. Species These six species are extant. *''Podocnemis erythrocephala'' – red-headed Amazon River turtle *''Podocnemis expansa'' – Arrau turtle *''Podocnemis lewyana'' – Magdalena River turtle *''Podocnemis sextuberculata'' – six-tubercled Amazon River turtle *''Podocnemis unifilis'' – yellow-spotted rive ...[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Podocnemis Skulls, Ventral And Side View, From The Osteology Of The Reptiles, Page 43
''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.''Podocnemis'' The Reptile Database. www.reptile-database.org. Four additional species are known only from fossils. These have pig-like noses but are not closely related to the . Species These six species are extant. *''Podocnemis erythrocephala'' – |
