Like all land animals, the therapsids were seriously affected by the Permian–Triassic extinction event, with the very successful gorgonopsians dying out altogether and the remaining groups, dicynodonts, therocephalians and cynodonts of a few species, each surviving into the Triassic. The dicynodonts, now represented by a single family of large stocky herbivores, the Kannemeyeridae, and the medium-sized cynodonts (including both carnivorous and herbivorous forms), flourished worldwide, throughout the Early and Middle Triassic. They died out across much of Pangea at the end of the Carnian (Late Triassic), although they continued for some time longer in the wet equatorial band and the south. Some exceptions were the still further derived eucynodonts. At least three groups of them survived. They all appeared in the Late Triassic epoch.
The therocephalians, relatives of the cynodonts, managed to survive the Permian-Triassic extinction and continued to diversify through the Early Triassic period. Approaching the end of the epoch, however, the therocephalians were declining to extinction and eventually became extinct, possibly due to climatic changes and competition from cynodonts and other animals struggling to survive.
Dicynodonts are thought to have become extinct before the end of the Triassic, but there is evidence that they survived the extinction. Their fossils have been found in Gondwana. Other animals that were common in the Triassic also took refuge here, such as the Temnospondyls. This is an example of Lazarus taxon.
Mammals, the only living therapsids, evolved in the Early Jurassic epoch. They radiated from a group of mammaliaformes that is related to the symmetrodonts. The mammaliaformes themselves evolved from probainognathians, a lineage of the eucynodont suborder.
The naris and palate of Lycaenodon Longiceps (Therapsida: Biarmosuchia), with comments on their early evolution in the therapsida
Sep 01, 2003; ABSTRACT-The anatomy of the external naris and anterior palate is described in detail for Lycaenodon longiceps, a morphologically...
Body Size and Growth Patterns in the Therocephalian Moschorhinus Kitchingi (Therapsida: Eutheriodontia) before and after the End-Permian Extinction in South Africa
Apr 01, 2013; Abstract.-The continuous fossil record of therocephalian therapsids (Eutheriodontia) across the PermoTriassic boundary and their...