Selmasaurus is an extinct genus of marine lizard belonging to the mosasaur family. It is classified as part of the Plioplatecarpinae subfamily alongside genera like Angolasaurus and Platecarpus. Two species are known, S. russelli and S. johnsoni; both are exclusively known from Santonian deposits in the United States.
Ctenospondylus is an extinct genus of sphenacodontid synapsid
Secodontosaurus is an extinct genus of "pelycosaur" synapsids that lived from between about 285 to 272 million years ago during the Early Permian. Like the well known Dimetrodon, Secodontosaurus is a carnivorous member of the Eupelycosauria family Sphenacodontidae and has a similar tall dorsal sail. However, its skull is long, low, and narrow, with slender jaws that have teeth that are very similar in size and shape—unlike the shorter, deep skull of Dimetrodon, which has large, prominent canine-like teeth in front and smaller slicing teeth further back in its jaws. Its unusual long, narrow jaws suggest that Secodontosaurus may have been specialized for catching fish or for hunting prey that lived or hid in burrows or crevices. Although no complete skeletons are currently known, Secodontosaurus likely ranged from about 2 to 2.7 metres (7–9 ft) in length, weighing up to 110 kilograms (250 lb).
Mycterosaurus is an extinct genus of amniotes belonging to the family Varanopidae. It is classified in the varanopid subfamily Mycterosaurinae. Mycterosaurus is the most primitive member of its family, existing from 290.1 to 272.5 MYA, known to Texas and Oklahoma. It lacks some features that its advanced relatives have.
Varanops is an extinct genus of Early Permian varanopid known from Texas and Oklahoma of the United States. It was first named by Samuel Wendell Williston in 1911 as a second species of Varanosaurus, Varanosaurus brevirostris. In 1914, Samuel W. Williston reassigned it to its own genus and the type species is Varanops brevirostris.
Casea is a genus of herbivorous caseid synapsids that lived during the late Lower Permian (Kungurian) in what is now Texas, United States. The genus is only represented by its type species, Casea broilii, named by Samuel Wendell Williston in 1910. The species is represented by a skull associated with a skeleton, a second skull, a partial skull with a better preserved dentition than that of the preceding skulls, and several incomplete postcranial skeletons. Three other Casea species were later erected, but these are considered today to be invalid or belonging to different genera. Casea was a small animal with a length of about 1.20 m and a weight of around 20 kg.
Gerobatrachus is an extinct genus of amphibamid temnospondyl that lived in the Early Permian, approximately 290 million years ago (Ma), in the area that is now Baylor County, Texas. When it was first described in 2008, Gerobatrachus was announced to be the closest relative of Batrachia, the group that includes modern frogs and salamanders. It possesses a mixture of characteristics from both groups, including a large frog-like head and a salamander-like tail. These features have led to it being dubbed a frogamander by the press. Some more recent studies place Gerobatrachus as the closest relative of Lissamphibia, the group that contains all modern amphibians including frogs, salamanders, and caecilians, or place modern amphibians far from Gerobatrachus within a group called Lepospondyli.
Acroplous is an extinct genus of dvinosaurian Temnospondyli within the family Eobrachyopidae.
Carrolla is an extinct genus of brachystelechid 'microsaur' that lived in the Lower Permian in North America. It was named in 1986 by American paleontologists Wann Langston and Everett Olson. The type species, Carrolla craddocki, is the only known species.
Pariotichus is an extinct genus of gymnarthrid microsaurs from the early Permian of Texas.
Trimerorhachis is an extinct genus of dvinosaurian temnospondyl within the family Trimerorhachidae. It is known from the Early Permian of the southwestern United States, with most fossil specimens having been found in the Texas Red Beds. The type species of Trimerorhachis, T. insignis, was named by American paleontologist Edward Drinker Cope in 1878. Cope named a second species from Texas, T. mesops, in 1896. The species T. rogersi and T. greggi are also from Texas, and the species T. sandovalensis is from New Mexico.
Tersomius is an extinct genus of dissorophoid temnospondyl within the family Micropholidae. It is known from the early Permian of North America.
Pasawioops is an extinct genus of early Permian dissorophoid temnospondyl within the clade Amphibamiformes.
Huskerpeton is an extinct genus of recumbirostran from the Early Permian period. They belong to the order Microsauria, which was established in 1863 by Dawson, and was quickly expanded to include many different small taxa. They lived in what is now Nebraska and Kansas. The holotype of Huskerpeton was uncovered at the Eskridge formation in Nebraska, which is part of how it got its name.
Scapanops is an extinct genus of dissorophid temnospondyl amphibian known from the Early Permian Nocona Formation of north-central Texas, United States. It contains only the type species Scapanops neglecta, which was named by Rainer R. Schoch and Hans-Dieter Sues in 2013. Scapanops differs from other dissorophids in having a very small skull table, which means that its eye sockets are unusually close to the back of the skull. The eye sockets are also very large and spaced far apart. Scapanops was probably small-bodied with a proportionally large head and short trunk and tail. Like other dissorophids, it probably spent most of its life on land.
Reiszerpeton is an extinct genus of dissorophid temnospondyl known from the Early Permian Archer City Formation of Texas. It is known solely from the holotype, MCZ 1911, a complete skull. This specimen was originally referred to the amphibamiform Tersomius texensis. A reappraisal of the holotype of T. texensis and a number of other referred specimens by Maddin et al. (2013) noted a number of differences from both T. texensis and amphibamiforms more broadly that suggested affinities with the Dissorophidae. This was confirmed by a phylogenetic analysis, which placed it as the sister taxon to the Eucacopinae. Reiszerpeton is known only from the type species, R. renascentis, which was named for Canadian paleontologist Robert Reisz. The species name refers to the recognition of Reisz as a "renaissance paleontologist." It is differentiated from other dissorophids by its small size, small and more numerous maxillary teeth, smooth cranial ornamentation, and greater distance between the orbit and the otic notch.
The Arroyo Formation, sometimes termed the Lower Clear Fork Formation, is a geologic formation in Texas. It preserves fossils dating back to the Kungurian stage of the Permian period. It is the lower-most portion of the Clear Fork Group, part of a series of fossiliferous Permian strata in the south-central United States known as the red beds.
Amphibamiformes is an unranked clade with Dissorophoidea created by Schoch (2018). It encompasses all of the taxa traditionally considered to be "amphibamids", branchiosaurids, and hypothetically lissamphibians under the traditional temnospondyl hypothesis of lissamphibian origins. These taxa are typically small-bodied dissorophoids and form the sister group to Olsoniformes, which comprises dissorophids and trematopids.
Rastosuchus is an extinct genus of stereospondyl temnospondyl within the family Rhinesuchidae. It contains one species, Rastosuchus hammeri, found in the Permian Rio do Rasto Formation of Brazil.
Phorcys is an extinct genus of gorgonopsian that lived during the Middle Permian period (Guadalupian) of what is now South Africa. It is known from two specimens, both portions from the back of the skull, that were described and named in 2022 as a new genus and species P. dubei by Christian Kammerer and Bruce Rubidge. The generic name is from Phorcys of Greek mythology, the father of the Gorgons from which the gorgonopsians are named after, and refers to its status as one of the oldest representatives of the group in the fossil record. Phorcys was recovered from the lowest strata of the Tapinocephalus Assemblage Zone (AZ) of the Beaufort Group, making it one of the oldest known gorgonopsians in the fossil record—second only to fragmentary remains of an indeterminate gorgonopsian from the older underlying Eodicynodon Assemblage Zone.
