Caseidae

Cotylorhynchus is an extinct genus of herbivorous caseid synapsids that lived during the late Lower Permian (Kungurian) and possibly the early Middle Permian (Roadian) in what is now the states of Texas and Oklahoma. The large number of specimens found make it the best-known caseid.

Caseidae are an extinct family of basal synapsids that lived from the Late Carboniferous to Middle Permian between about 300 and 265 million years ago. Fossils of these animals come from the south-central part of the United States (Texas, Oklahoma, and Kansas), from various parts of Europe (European Russia, France, Germany, Sardinia, and Poland), and possibly from South Africa if the genus Eunotosaurus is indeed a caseid as some authors proposed in 2021. Caseids show great taxonomic and morphological diversity. The most basal taxa were small insectivorous and omnivorous forms that lived mainly

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 (the holotype FMNH UC 656), a second skull (FMNH UC 698), a partial skull with a better preserved dentition than that of the preceding skulls (FMNH UC 1011), and several incomplete postcranial skeletons. Three other Casea species were later erected, but these are considered today to be

Ennatosaurus is an extinct genus of caseid synapsid that lived during the Middle Permian (late Roadian - early Wordian) in northern European Russia. The genus is only represented by its type species, Ennatosaurus tecton, which was named in 1956 by Ivan Antonovich Efremov. The species is known from at least six skulls associated with their lower jaws (two of them preserved with the hyoid apparatus), as well as from the postcranial bones of several juvenile individuals. Ennatosaurus has the typical caseid skull with a short snout tilted forward and very large external nares. However, it differs

Caseoides is an extinct genus of large caseid synapsids that lived in the Kungurian Age (late Early Permian epoch). It was about long, and like many other caseids, it was herbivorous and aquatic. It weighed between . Its fossils were found in San Angelo Formation, Texas. Caseoides was very similar to Casea, but was slightly larger in size. Caseoides was a heavily built creature, as are most of the Caseids (except Caseopsis). In the development of its proportionally thick, stout limbs it represents the culmination of the Casea lineage. Its relatives became smaller during the Roadian Age. Only p

Angelosaurus is an extinct genus of herbivorous caseid synapsids that lived during the late Lower Permian (Kungurian) and early Middle Permian (Roadian) in what is now Texas and Oklahoma. Like other herbivorous caseids, it had a small head, large barrel-shaped body, long tail, and massive limbs. Angelosaurus differs from other caseids by the extreme massiveness of its bones, particularly those of the limbs, which show a strong development of ridges, processes, and rugosities for the attachment of muscles and tendons. Relative to its body size, the limbs of Angelosaurus were shorter and wider t

Oromycter is an extinct genus of caseid synapsids from the Early Permian of Oklahoma. The sole and type species, Oromycter dolesorum, was named in 2005 by Robert R. Reisz.

Datheosaurus ("Dathe's lizard") is an extinct genus of caseasaur. It was at least in length. It lived during the Latest Carboniferous to Early Permian in Poland. It was named for Ernst Dathe (1845–1917), the German geologist who first announced the fossil find.

Caseopsis is an extinct genus of large pelycosaurs that was about long. Caseopsis lived in the late Early Permian epoch (Kungurian Age), before the pelycosaurs were replaced by the more advanced therapsids (in the next age). It was a lightly built, agile creature. It may have been possible for this species to outpace and escape large predators such as Dimetrodon.

Trichasaurus is an extinct genus of caseid synapsids.

Alierasaurus is an extinct genus of caseid synapsid that lived during the early Middle Permian (Roadian) in what is now Sardinia. It is represented by a single species, the type species Alierasaurus ronchii. Known from a very large partial skeleton found within the Cala del Vino Formation, Alierasaurus is one of the largest known caseids. It closely resembles Cotylorhynchus, another giant caseid from the San Angelo Formation in Texas. The dimensions of the preserved foot elements and caudal vertebrae suggest an estimated total length of about for Alierasaurus. In fact, the only anatomical feat

Arisierpeton is an extinct genus of synapsids from the Early Permian Garber Formation (Sumner Group) of Richards Spur, Oklahoma. It contains a single species, Arisierpeton simplex.

Lalieudorhynchus is an extinct genus of caseid synapsids that lived during the Guadalupian (= Middle Permian) in what is now Southern France. The genus is only known by its type species, Lalieudorhynchus gandi, which was named in 2022 by Ralf Werneburg, Frederik Spindler, Jocelyn Falconnet, Jean-Sébastien Steyer, Monique Vianey-Liaud, and Joerg W. Schneider. Lalieudorhynchus is represented by a partial postcranial skeleton discovered in the Lodève basin in the central part of the Hérault department in the Occitanie region. It belongs to an individual measuring approximately in length. The degr

Callibrachion is an extinct genus of caseid synapsids that lived in east-central France during the Lower Permian (Asselian). The holotype and only known specimen (MNHN.F.AUT490) is represented by an almost complete postcranial skeleton associated with skull fragments discovered at the end of the 19th century in the Permian Autun basin in Saône-et-Loire department, in the Bourgogne-Franche-Comté region. It belongs to an immature individual measuring less than 1.50 m in length. Callibrachion was long considered a junior synonym of the genus Haptodus and classified among the sphenacodontid pelyco

Euromycter is an extinct genus of caseid synapsids that lived in what is now Southern France during the Early Permian (late Artinskian) about 285 million years ago. The holotype and only known specimen of Euromycter (MNHN.F.MCL-2) includes the complete skull with lower jaws and hyoid apparatus, six cervical vertebrae with proatlas, anterior part of interclavicle, partial right clavicle, right posterior coracoid, distal head of right humerus, left and right radius, left and right ulna, and complete left manus. It was collected by D. Sigogneau-Russell and D. Russell in 1970 at the top of the M1

Eocasea is an extinct genus of caseid synapsids from the Late Pennsylvanian of Kansas. It is known from a single type species, Eocasea martini.

Ruthenosaurus is an extinct genus of caseid synapsids that lived in what is now Southern France during the Early Permian (late Artinskian) about 285 million years ago. It is known from the holotype MNHN.F.MCL-1 an articulated partial postcranial skeleton. It was collected by D. Sigogneau-Russell and D. Russell in 1970 in the upper part of the M2 Member, Grès Rouge Group, in the Rodez Basin, near the village of Valady (département of Aveyron), in Occitanie Region. It was first named by Robert R. Reisz, Hillary C. Maddin, Jörg Fröbisch and Jocelyn Falconnet in 2011, and the type species is Ruthe

Martensius is an extinct genus of caseid synapsid from the Early Permian of Germany. The type species is '''Martensius bromackerensis.'''