Guadalupian extinctions

Dinocephalians (terrible heads) are a clade of large-bodied early therapsids that flourished in the Early and Middle Permian between 279.5 and 260 million years ago (Ma), but became extinct during the Capitanian mass extinction event. Dinocephalians included herbivorous, carnivorous, and omnivorous forms. Many species had thickened skulls with many knobs and bony projections. Dinocephalians were the first non-mammalian therapsids to be scientifically described and their fossils are known from Russia, China, Brazil, South Africa, Zimbabwe, and Tanzania.

Sphenacodontidae (Greek: "wedge point tooth family") is an extinct family of sphenacodontoid synapsids. Small to large, advanced, carnivorous, Late Pennsylvanian to middle Permian "pelycosaurs". The most recent one, Dimetrodon angelensis, is from the latest Kungurian or, more likely, early Roadian San Angelo Formation. However, given the notorious incompleteness of the fossil record, a recent study concluded that the Sphenacodontidae may have become extinct as recently as the early Capitanian. Primitive forms were generally small (60 cm to 1 meter), but during the later part of the early

Caseasauria is one of the two main clades of early synapsids, the other being the Eupelycosauria. Caseasaurs are currently known only from the Late Carboniferous and the Permian, and include two superficially different families, the small insectivorous or carnivorous Eothyrididae, and the large, herbivorous Caseidae. These two groups share a number of specialised features associated with the morphology of the snout and external naris.

Varanopidae is an extinct family of amniotes known from the Late Carboniferous to Middle Permian that resembled monitor lizards (with the name of the group deriving from the monitor lizard genus Varanus) and may have filled a similar niche. Typically, they are considered to be relatively basal synapsids (and thus more closely related to mammals than to reptiles), although some studies from the late 2010s recovered them being taxonomically closer to diapsid reptiles; recent studies from the early 2020s support their traditional placement as synapsids on the basis of high degree of bone labyrint

Tapinocephalidae was an advanced family of tapinocephalians. It is defined as the clade containing Ulemosaurus, Tapinocaninus, and the Tapinocephalinae. They are known from both Russia and South Africa. In all probability, the Tapinocephalidae had a worldwide (Pangean) distribution. They flourished briefly during the Wordian and Capitanian ages, radiating into several lineages, existing simultaneously, and differing mainly in details of the skull and, to an even lesser degree, the skeleton. It is not clear how such similar animals could each find their own ecological niche, but such was obviou

Estemmenosuchidae is an extinct family of large, very early herbivorous therapsids that flourished during the Guadalupian period. They are distinguished by horn-like structures, probably for display or agonistic behavior. Apart from the best known genus, Estemmenosuchus, the group is poorly known. To date, their fossils are known only from the Perm region of Russia (a region referred to by Russian paleontologists as the Cis-Urals).

Anteosauridae is an extinct family of large carnivorous dinocephalian therapsids that are known from the Middle Permian of Asia, Africa, and South America.These animals were by far the largest predators of the Permian period, with skulls reaching 80 cm in length in adult individuals, far larger than the biggest gorgonopsian.

The Tapinocephalia are one of the major groups of dinocephalian therapsids and the major herbivorous group. Tapinocephalia has been found to consist of three clades: Styracocephalidae, Titanosuchidae, and the very successful Tapinocephalidae. Notable tapinocephalians include Moschops, Tapinocephalus, and Titanosuchus.

Titanosuchidae is an extinct family of dinocephalians known only from the middle Permian Tapinocephalus Assemblage Zone of South Africa.

Anteosaurs are a group of large, primitive carnivorous dinocephalian therapsids with large canines and incisors and short limbs, that are known from the Middle Permian of South Africa, Russia, China, and Brazil. Some grew very large, with skulls long, and were the largest predators of their time. They died out at the end of the Middle Permian, possibly as a result of the extinction of the herbivorous Tapinocephalia on which they may have fed.

Proetidae is a family of proetid trilobites. The first species appeared in the Upper Ordovician, and the last genera survived until the Middle Permian. However, if the closely related family Phillipsiidae is actually a subfamily of Proetidae, then the proetids of Proetidae survive until the end of the Permian, where the last perish during the Permian–Triassic extinction event.

mass extinction that occurred 273 million years ago in the early Guadalupian of the Permian period

Eotitanosuchidae is an extinct family of biarmosuchian therapsids. The Eotitanosuchidae were large predatory therapsids of the Wordian epoch. It was once considered to belong to a separate infraorder of therapsids called Eotitanosuchia.

Syodontinae is a group of dinocephalian therapsids. It is one of two subfamilies in the family Anteosauridae, the other being Anteosaurinae. They are known from the Middle Permian Period of what is now Russia and South Africa. One of the best known syodontines is Syodon from Russia. The South African form Australosyodon, is one of the earliest known Gondwanan anteosaurs.

Anomocephaloidea is a clade of basal anomodont therapsids related to the dicynodonts known from what is now South Africa and Brazil during the Middle Permian. It includes only two species, Anomocephalus africanus (the clade's namesake) from the Karoo Basin of South Africa and Tiarajudens eccentricus from the Paraná Basin of Brazil. Anomocephaloidea was named in 2011 with the discovery of Tiarajudens, although Anomocephalus itself has been known since 1999.