Anomocephaloidea is a

clade A clade (), also known as a monophyletic group or natural group, is a group of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree. Rather than the English term, ...

(evolutionary grouping) of

anomodont Anomodontia is an extinct group of non-mammalian therapsids from the Permian and Triassic periods. By far the most speciose group are the dicynodonts, a clade of beaked, tusked herbivores.Chinsamy-Turan, A. (2011) ''Forerunners of Mammals: Ra ...

therapsid Therapsida is a major group of eupelycosaurian synapsids that includes mammals, their ancestors and relatives. Many of the traits today seen as unique to mammals had their origin within early therapsids, including limbs that were oriented more ...

s that existed in

Gondwana Gondwana () was a large landmass, often referred to as a supercontinent, that formed during the late Neoproterozoic (about 550 million years ago) and began to break up during the Jurassic period (about 180 million years ago). The final stages ...

during the

Middle Permian The Guadalupian is the second and middle series/epoch of the Permian. The Guadalupian was preceded by the Cisuralian and followed by the Lopingian. It is named after the Guadalupe Mountains of New Mexico and Texas, and dates between 272.95 ± 0. ...

and includes two species, ''

Anomocephalus africanus ''Anomocephalus'' is an extinct genus of primitive anomodonts and belongs to the clade Anomocephaloidea. The name is said to be derived from the Greek word ''anomos'' meaning lawless and ''cephalos'' meaning head. The proper word for head in Gr ...

'' from South Africa and ''

Tiarajudens eccentricus ''Tiarajudens'' (" Tiaraju tooth") is an extinct genus of saber-toothed herbivorous anomodonts which lived during the Middle Permian period (Capitanian stage) in what is now Rio Grande do Sul, Brazil. It is known from the holotype UFRGS P ...

'' from Brazil, both of which are characterized by large body size and teeth that fit tightly together or occlude. Anomocephaloidea is among the most basal groups of anomodonts, the other being

Venyukovioidea Venyukovioidea is an infraorder of anomodont therapsids related to dicynodonts from the Permian of Russia. They have also known as Venjukovioidea, as well as by the similar names Venyukoviamorpha or Venjukoviamorpha in literature. This in part ow ...

, which differs in being a

Laurasia Laurasia () was the more northern of two large landmasses that formed part of the Pangaea supercontinent from around ( Mya), the other being Gondwana. It separated from Gondwana (beginning in the late Triassic period) during the breakup of Pan ...

n clade of mostly small-bodied species. Anomocephaloidea was named in 2011 with the discovery of ''Tiarajudens''; ''Anomocephalus'' had been known since 1999, but was unique among anomodonts until ''Tiarajudens'' was described. Both ''Anomocephalus'' and ''Tiarajudens'' were

herbivore A herbivore is an animal anatomically and physiologically adapted to eating plant material, for example foliage or marine algae, for the main component of its diet. As a result of their plant diet, herbivorous animals typically have mouthpart ...

s, although the latter possessed a pair of saber-like

canine teeth In mammalian oral anatomy, the canine teeth, also called cuspids, dog teeth, or (in the context of the upper jaw) fangs, eye teeth, vampire teeth, or vampire fangs, are the relatively long, pointed teeth. They can appear more flattened howeve ...

that may have been used in display or combat with other individuals of the same species. Although Anomocephaloidea was short-lived and had a limited geographic distribution, it was part of a larger

evolutionary radiation An evolutionary radiation is an increase in taxonomic diversity that is caused by elevated rates of speciation, that may or may not be associated with an increase in morphological disparity. Radiations may affect one clade or many, and be rapid ...

of anomodonts in the Middle Permian characterized by the evolution of a diverse array of new morphological characteristics and ecological roles, and that would later lead to the rise of

Dicynodontia Dicynodontia is an extinct clade of anomodonts, an extinct type of non-mammalian therapsid. Dicynodonts were herbivorous animals with a pair of tusks, hence their name, which means 'two dog tooth'. Members of the group possessed a horny, typicall ...

, the largest clade within Anomodontia and one of the most successful groups of

tetrapod Tetrapods (; ) are four-limbed vertebrate animals constituting the superclass Tetrapoda (). It includes extant and extinct amphibians, sauropsids ( reptiles, including dinosaurs and therefore birds) and synapsids (pelycosaurs, extinct theraps ...

s in the Permian. Below is a

cladogram A cladogram (from Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an evolutionary tree because it does not show how ancestors are related to d ...

from Cisneros ''et al.'' (2011) showing the phylogenetic position of Anomocephaloidea:

References

{{Taxonbar, from=Q18609917 Anomodonts Permian synapsids Guadalupian first appearances Guadalupian extinctions