Microsauria is an extinct, possibly polyphyletic order of amphibians from the late Carboniferous and early Permian periods. It is the most diverse and species-rich group of lepospondyls. Recently, Microsauria has been considered paraphyletic, as several other non-microsaur lepospondyl groups such as Lysorophia seem to be nested in it. Microsauria is now commonly used as a collective term for the grade of lepospondyls that were originally classified as members of Microsauria.
Dendrerpeton is a genus of an extinct group of temnospondyl amphibians. Its fossils have been found primarily in the Joggins Formation of Eastern Canada and in Ireland. It lived during the Carboniferous and is said to be around 309–316 million years of age, corresponding to more specifically the Westphalian (stage) age. Of terrestrial temnospondyl amphibians evolution, it represents the first stage. Although multiple species have been proposed, the species unanimously recognized is D. acadianum. This species name comes from “Acadia” which is a historical name for the Nova Scotia region as a French colony. It refers to the location of the coal field at which the fossil was found.
Megalocephalus is an extinct genus of baphetid amphibian from the late Carboniferous of the British Isles and the United States (Ohio). It contains two species, M. pachycephalus and M. lineolatus.
The Allegheny Group, often termed the Allegheny Formation, is a Pennsylvanian-age geological unit in the Appalachian Plateau. It is a major coal-bearing unit in the eastern United States, extending through western and central Pennsylvania, western Maryland and West Virginia, and southeastern Ohio. Fossils of fishes such as Bandringa are known from the Kittaning Formation, which is part of the Allegheny Group.
Astreptorhachis is an extinct genus of Late Carboniferous dissorophoid temnospondyl within the family Dissorophidae. It is known only from one species, Astreptorhachis ohioensis, that was collected from Jefferson County, Ohio by the Ohio Geological Survey in 1953 and described by Peter Vaughn in 1971. The holotype and only known specimen consists of a few neural spines and is currently reposited in the Smithsonian Museum of Natural History. The genus name derives from the Greek words astreptos ("inflexible") and rhachis ("backbone"). The specimen was recognized as being similar to the dissorophid Platyhystrix rugosus from the southwestern United States in have greatly elongate neural spines. Astreptorhachis is differentiated from Platyhystrix by the fusion of successive neural spines and the extensively developed tubercles that cover the external surfaces. It is speculated that the elongation of the spines served to stiffen the backbone, being advantageous for terrestrial locomotion, but the purpose of the fusion of successive spines remained unclear in the absence of other material of this taxon.
Arizonerpeton is an extinct genus of nectridean lepospondyl. It contains a single species, Arizonerpeton wellsi. It lived in what is now the Swisshelm Mountains of modern-day Arizona, United States. This locality belongs to the Black Prince Limestone Formation, which is dated to the middle Pennsylvanian sub-period of the Carboniferous period.
Actiobates is an extinct genus of trematopid temnospondyl that lived during the Late Carboniferous. It is known from the Garnett Quarry in Kansas.
Colosteus is an extinct genus of colosteid tetrapod from the Late Carboniferous of Ohio. Its remains have been found at the Linton site in Saline Township, Ohio, where it is one of the most common tetrapods, and at the Five Points site in Mahoning County, Ohio. It was an elongate, aquatic form with a flattened and pointed head, greatly reduced limbs, two premaxillary tusks, and heavy scalation. It would have reached about 1 m (3.2 ft) in length.
Elfridia is a poorly known extinct genus of microsaur within the family Gymnarthridae.
Diceratosaurus is an extinct genus of nectridean lepospondyl within the family Keraterpetontidae. Fossils of Diceratosaurus were first described by Edward Drinker Cope in 1874. The species D. brevirostris is well known from Jefferson County, Ohio, with approximately 50 specimens having been collected from the Ohio Diamond Coal Mine. The mine was situated in the village of Linton, which became obscure soon after operations were completed and the mine closed in 1921.
Llistrofus is an extinct genus of early Permian microsaur within the family Hapsidopareiidae that is known from Oklahoma.
Odonterpeton is an extinct genus of "microsaur" from the Late Carboniferous of Ohio, containing the lone species Odonterpeton triangulare. It is known from a single partial skeleton preserving the skull, forelimbs, and the front part of the torso. The specimen was found in the abandoned Diamond Coal Mine of Linton, Ohio, a fossiliferous coal deposit dated to the late Moscovian stage, about 310 million years ago.
Platyrhinops is an extinct genus amphibamid temnospondyl from the Late Carboniferous of Ohio and the Czech Republic. It is known from many partial skeletons from the Linton site in Saline Township, Ohio and at least 6 partial specimens from the Nýřany site from the Nýřany Member of the Kladno Formation in the Czech Republic.
Pleuroptyx is an extinct genus of prehistoric amphibian known from the Late Carboniferous (Pennsylvanian) of Ohio. The type species is Pleuroptyx clavatus.
Schoenfelderpeton is an extinct genus of prehistoric amphibian. It is a sister taxon to Leptorophus tener.
Stegops is an extinct genus of euskelian temnospondyl from the Late Carboniferous of the eastern United States. Fossils are known from the Pennsylvanian coal deposits of Linton, Ohio. It was once classified in the eryopoid family Zatrachydidae because it and other zatrachydids have spikes extending from the margins of its skull, but it is now classified as a dissorophoid that independently evolved spikes. Stegops was first named by American paleontologist Edward Drinker Cope in 1885, with his description of the type species Stegops divaricata. Cope had also named a species of Sauropleura from Linton in 1875, which he called Sauropleura newberryi. This species was later synonymized with Stegops divaricata when the type specimen of S. newberryi was prepared and found to be a large specimen of Stegops.
Adamanterpeton is a genus of Edopoid Temnospondyl within the family Cochleosauridae. The type species A. ohioensis was named in 1998 and is currently the only known species within this genus. Adamanterpeton is rare in the Linton vertebrate assemblage, with other amphibians like Sauropleura, Ophiderpeton, and Colosteus being more common. Unlike other Linton vertebrates, Adamanterpeton may have been adapted to a terrestrial lifestyle.
Eusauropleura is an extinct genus of gephyrostegid reptiliomorph from the Pennsylvanian of Linton, Ohio. The type species and only species, Eusauropleura digitata, was first described by American paleontologist Edward Drinker Cope in 1868 as Sauropleura digitata. In 1930, paleontologist Alfred Romer placed the species in the new genus Eusauropleura. Romer considered S. digitata to be a reptile or a more primitive relative of reptiles, making it only distantly related to Sauropleura, which is a lepospondyl amphibian.
Andersonerpeton is an extinct genus of aïstopod from the Bashkirian of Nova Scotia, Canada. It is known from a single jaw, which shares an unusual combination of features from both other aistopods and from stem-tetrapod tetrapodomorph fish. As a result, Andersonerpeton is significant for supporting a new classification scheme which states that aistopods evolved much earlier than previously expected. The genus contains a single species, A. longidentatum, which was previously believed to have been a species of the microsaur Hylerpeton.
Macrerpeton is a genus of edopoid temnospondyl within the family Cochleosauridae. It contains a single species, Macrerpeton huxleyi. It was discovered in the fossil-rich Allegheny Formation of Linton, Ohio.
