Diadectidae

Diadectes (meaning crosswise-biter) is an extinct genus of large reptiliomorphs that lived during the early Permian period (Artinskian-Kungurian stages of the Cisuralian epoch, between 290 and 272 million years ago). Diadectes was one of the first herbivorous tetrapods, and also one of the first fully terrestrial vertebrates to attain large size.

Diadectidae is an extinct family of early tetrapods that lived in what is now North America and Europe during the Late Carboniferous and Early Permian, and in Asia during the Late Permian. They were the first herbivorous tetrapods, and also the first fully terrestrial animals to attain large sizes. Footprints indicate that diadectids walked with an erect posture.

Orobates is an extinct genus of diadectid reptiliomorphs that lived during the Early Permian. Its fossilised remains were found in Germany. A combination of primitive and derived traits (i.e. autapomorphic and plesiomorphic) distinguish it from all other well-known members of Diadectidae, a family of herbivorous reptiliomorphs. It weighed about 4 kg and appears to have been part of an upland fauna, browsing on high fibre plants. thumb|left|Restoration

Diasparactus is an extinct genus of diadectid reptiliomorphs, a group quite closely related to the amniotes, and paralleling some of their features. Like all advanced diadectids, Diasparactus was a herbivore, though not as large as its more well known relative Diadectes.

Desmatodon is an extinct genus of diadectid reptiliomorph. With fossils found from the Kasimovian (Missourian) stage of the Late Carboniferous of Pennsylvania, Colorado, and New Mexico in the United States, Desmatodon is the oldest known diadectid, the group of the first known herbivorous tetrapods. Later members obtained larger sizes, with Desmatodon being somewhat smaller, though its actual size is unknown due to the fragmentary nature of the fossils. Two species are currently recognized: the type species D. hollandi and the species D. hesperis.

Phanerosaurus is an extinct genus of diadectid reptiliomorph from the Early Permian of Germany. Fossils are known from the Leukersdorf Formation near Zwickau. German paleontologist Christian Erich Hermann von Meyer named the type species P. naumanni in 1860 on the basis of several sacral and presacral vertebrae. A second species, P. pugnax, was named in 1882 but placed in its own genus Stephanospondylus in 1905.