Portal:Reptiles

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The Reptiles Portal

American alligator (Alligator mississippiensis) at the Oasis visitor center in Big Cypress National Preserve, Florida
American alligator (Alligator mississippiensis) at the Oasis visitor center in Big Cypress National Preserve, Florida
Reptiles 2021 collage.jpg
Reptilians by saurian clade listed in top-to-bottom order: six lepidosaurs and six archelosaurs
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birds. Living reptiles comprise turtles, crocodilians, squamates (lizards and snakes) and rhynchocephalians (tuatara). As of March 2022, the Reptile Database includes about 11,700 species. In the traditional Linnaean classification system, birds are considered a separate class to reptiles. However, crocodilians are more closely related to birds than they are to other living reptiles, and so modern cladistic classification systems include birds within Reptilia, redefining the term as a clade. Other cladistic definitions abandon the term reptile altogether in favor of the clade Sauropsida, which refers to all amniotes more closely related to modern reptiles than to mammals. The study of the traditional reptile orders, customarily in combination with the study of modern amphibians, is called herpetology
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The earliest known proto-reptiles originated around 312 million years ago during the

dinosaurs alongside many species of crocodyliforms, and squamates (e.g., mosasaurs). Modern non-bird reptiles inhabit all the continents except Antarctica
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Reptiles are tetrapod

oviparous, although several species of squamates are viviparous, as were some extinct aquatic clades  – the fetus develops within the mother, using a (non-mammalian) placenta rather than contained in an eggshell. As amniotes, reptile eggs are surrounded by membranes for protection and transport, which adapt them to reproduction on dry land. Many of the viviparous species feed their fetuses through various forms of placenta analogous to those of mammals, with some providing initial care for their hatchlings. Extant reptiles range in size from a tiny gecko, Sphaerodactylus ariasae, which can grow up to 17 mm (0.7 in) to the saltwater crocodile, Crocodylus porosus, which can reach over 6 m (19.7 ft) in length and weigh over 1,000 kg (2,200 lb). (Full article...
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Reptile types