Temnospondyli or temnospondyls is a diverse ancient order of small to giant tetrapods—often considered primitive amphibians—that flourished worldwide during the Carboniferous, Permian and Triassic periods, with fossils being found on every continent. A few species continued into the Jurassic and Early Cretaceous periods, but all had gone extinct by the Late Cretaceous. During about 210 million years of evolutionary history, they adapted to a wide range of habitats, including freshwater, terrestrial, and even coastal marine environments. Their life history is well understood, with fossils known from the larval stage, metamorphosis and maturity. Most temnospondyls were semiaquatic, although some were almost fully terrestrial, returning to the water only to breed. These temnospondyls were some of the first vertebrates fully adapted to life on land. Although temnospondyls are amphibians, many had characteristics such as scales and armour-like bony plates that distinguish them from the modern soft-bodied lissamphibians.
Trematosauroidea are an important group of Triassic temnospondyl amphibians. They flourished briefly during the Early Triassic, occurring worldwide before declining at the start of the Middle Triassic, although the group continued until the Late Triassic. They were medium-sized temnospondyls with wedge-shaped tails, narrow skulls, and, in advanced forms, elongated snouts. The latter feature was probably an adaptation for feeding on fish. The largest and most specialized family, the Trematosauridae, are the only batrachomorphs to have adapted to a marine lifestyle with the exception of the modern crab-eating frog.
Mastodonsaurus is an extinct genus of temnospondyl from the Middle Triassic of Europe. It belongs to a Triassic group of temnospondyls called Capitosauria, characterized by their large body size and presumably aquatic lifestyles. Mastodonsaurus remains one of the largest amphibians known, and may have exceeded 6 meters in length.
The Stereospondyli are a group of extinct temnospondyl amphibians that existed primarily during the Mesozoic period. They are known from all seven continents and were common components of many Triassic ecosystems, likely filling a similar ecological niche to modern crocodilians prior to the diversification of pseudosuchian archosaurs.
Parotosuchus is an extinct genus of capitosaurian temnospondyls within the family Mastodonsauridae. Fossils are known from the Early Triassic of Europe, Africa, Australia, and Antarctica. It was about 2 metres (6.6 ft) long and likely lived in aquatic environments such as lakes and rivers. Parotosuchus was covered in a scaly skin, unlike the smooth skin of modern-day amphibians, and probably moved with an eel-like motion in the water.
Eryosuchus is an extinct genus of capitosauroid temnospondyl from the Middle Triassic of northern Russia. It was a very large predator: the largest specimen known could reach up to 3.5 m (11.5 ft) in length, with a skull over 1 m long.
Cyclotosaurus is an extinct genus of temnospondyl within the family Mastodonsauridae. It was of great size for an amphibian, had an elongated skull up to 56 cm (22 in).
Eocyclotosaurus is an extinct genus of mastodonsauroid temnospondyl from the Middle Triassic (Anisian). The name Eocyclotosaurus means "dawn round-eared lizard". It is characterized as a capitosauroid with a long and slender snout, closed otic fenestra, and small orbits. It measured over one metre and had a 22 cm skull.
Benthosuchus is an extinct genus of temnospondyl amphibian from the Early Triassic of Russia. It was primarily aquatic, living in rivers and lakes. Multiple species are known, with the largest reaching about 2.5 meters in length.
Lydekkerinidae is a family of stereospondyl temnospondyls that lived in the Early Triassic period. During this time period, lydekkerinids were widely distributed, with putative remains reported from Russia, Greenland, India, South Africa, Madagascar, Australia, and Antarctica. In contrast to most other stereospondyls, lydekkerinids were relatively small-bodied. The type genus is Lydekkerina, the namesake of the family and the best-known lydekkerinid.
Mastodonsauridae is a family of capitosauroid temnospondyls. Fossils belonging to this family have been found in North America, Greenland, Europe, Asia, and Australia. The family Capitosauridae is synonymous with Mastodonsauridae.
Lydekkerina is an extinct genus of stereospondyl temnospondyl. It is the type genus of the family Lydekkerinidae. Fossils have been collected from Early Triassic deposits in South Africa and Australia. The type species is L. huxleyi, first described in 1889. While most other stereospondyls were semiaquatic, Lydekkerina was exclusively terrestrial.
Laccosaurus is an extinct monotypic genus of rhinesuchid temnospondyl, the type species being Laccosaurus watsoni.
Odenwaldia is an extinct genus of mastodonsauroid temnospondyl within the family Heylerosauridae.
Plagiosuchus is an extinct genus of plagiosaurid temnospondyl. It is known from several collections from the Middle Triassic of Germany.
Capitosauria is an extinct group of large temnospondyl amphibians with simplified stereospondyl vertebrae. Mainly living as piscivores in lakes and rivers, the Capitosauria and its sister taxon Trematosauria were the only major labyrinthodonts that existed during the Mesozoic in ecological niches broadly similar to those of modern crocodiles, and some grew to very large sizes. At 6 meters in length, the Mid-Triassic Mastodonsaurus giganteus is not only thought to have been the largest capitosaur, but possibly also the largest amphibian to have lived. The latest known remains are from the Rhaetian of Germany and are referred to Cyclotosaurus.
The Amphibamidae are an ancient family of dissorophoid temnospondyls known from Late Carboniferous-Early Permian strata in the United States.
Vladlenosaurus is an extinct genus of capitosaurian temnospondyl from Russia. It lived during the late Vetlugian. Based on the type of deposits it was found in, Vladlenosaurus probably inhabited lacustrine, or lake, habitats. The type species is V. alexeyevi, named in 2000.
Edingerella is an extinct genus of temnospondyl amphibian from the Early Triassic of Madagascar. It is a basal capitosaur closely related to Watsonisuchus.
The Erfurt Formation, also known as the Lower Keuper, is a stratigraphic formation of the Keuper group and the Germanic Trias supergroup. It was deposited during the Ladinian stage of the Triassic period. It lies above the Upper Muschelkalk and below the Middle Keuper.
