Editing Therapsida (section)

==Classification==
{{cladogram|caption=The Hopson and Barghausen paradigm for therapsid relationships|clades=
{{clade
|label1='''Therapsida'''
|1 = {{clade
 |1 = [[Biarmosuchia]]
 |2 = {{clade
  |1 = [[Dinocephalia]]
  |2 = {{clade
   |1 = [[Anomodontia]]
   |2 = {{clade
    |1 = [[Gorgonopsia]]
    |2 = {{clade
     |1 = [[Therocephalia]]
     |2 = [[Cynodontia]]
     }}
    }}
   }}
  }}
 }}
}}

}}
Six major groups of therapsids are generally recognized: Biarmosuchia, Dinocephalia, Anomodontia, Gorgonopsia, Therocephalia and Cynodontia. A clade uniting therocephalians and cynodonts, called [[Eutheriodontia]], is well supported, but relationships among the other four clades are controversial.<ref name=AngielczykKammerer2018/> The most widely accepted hypothesis of therapsid relationships, the Hopson and Barghausen paradigm, was first proposed in 1986. Under this hypothesis, biarmosuchians are the earliest-diverging major therapsid group, with the other five groups forming the Eutherapsida, and within Eutherapsida, gorgonopsians are the sister taxon of eutheriodonts, together forming the [[Theriodontia]]. Hopson and Barghausen did not initially come to a conclusion about how dinocephalians, anomodonts and theriodonts were related to each other, but subsequent studies suggested that anomodonts and theriodonts should be classified together as the Neotherapsida. However, there remains debate over these relationships; in particular, some studies have suggested that anomodonts, not gorgonopsians, are the sister taxon of Eutheriodontia, other studies have found dinocephalians and anomodonts to form a clade, and both the phylogenetic position and monophyly of Biarmosuchia remain controversial.

In addition to the six major groups, there are several other lineages and species of uncertain classification. ''[[Raranimus]]'' from the early Middle Permian of China is likely to be the earliest-diverging known therapsid.<ref>{{Cite journal |last1=Duhamel |first1=A. |last2=Benoit |first2=J. |last3=Rubidge |first3=B. S. |last4=Liu |first4=J. |name-list-style=amp |date=August 2021 |title=A re-assessment of the oldest therapsid Raranimus confirms its status as a basal member of the clade and fills Olson's gap |url=https://link.springer.com/10.1007/s00114-021-01736-y |journal=The Science of Nature |language=en |volume=108 |issue=4 |pages=26 |bibcode=2021SciNa.108...26D |doi=10.1007/s00114-021-01736-y |issn=0028-1042 |pmid=34115204 |s2cid=235403632|url-access=subscription }}</ref> ''[[Tetraceratops]]'' from the Early Permian of the United States has been hypothesized to be an even earlier-diverging therapsid,<ref name="Laurin1996"/><ref name="Amson2011"/> but more recent study has suggested it is more likely to be a non-therapsid sphenacodontian.<ref name="Spindler2020"/>
{{Further|topic=the dubious genus of non-mammalian therapsid|Cynodraco}}

===Biarmosuchia===
{{Main|Biarmosuchia}}
[[Image:Biarmosuchus BW.jpg|thumb|200px|''[[Biarmosuchus]]'', a [[biarmosuchia]]n]]

Biarmosuchia is the most recently recognized therapsid clade, first recognized as a distinct lineage by Hopson and Barghausen in 1986 and formally named by Sigogneau-Russell in 1989. Most biarmosuchians were previously classified as gorgonopsians. Biarmosuchia includes the distinctive [[Burnetiamorpha]], but support for the monophyly of Biarmosuchia is relatively low. Many biarmosuchians are known for extensive cranial ornamentation.

===Dinocephalia===
{{Main|Dinocephalia}}
[[Image:Titanophoneus_3.jpg|right|thumb|200px|Two genera of [[dinocephalia]]ns : ''[[Titanophoneus]]'' (an [[anteosaur]]) devouring a ''[[Ulemosaurus]]'' (a [[tapinocephalia]]n)]]
Dinocephalia comprises two distinctive groups, the [[Anteosauria]] and [[Tapinocephalia]].

Historically, carnivorous dinocephalians, including both anteosaurs and titanosuchids, were called titanosuchians and classified as members of Theriodontia, while the herbivorous Tapinocephalidae were classified as members of Anomodontia.

===Anomodontia===
{{Main|Anomodontia}}
[[Image:Lystr georg1DB.jpg|right|thumb|''[[Lystrosaurus]]'', a [[dicynodont]] anomodont]]
Anomodontia includes the dicynodonts, a clade of tusked, beaked herbivores, and the most diverse and long-lived clade of non-cynodont therapsids. Other members of Anomodontia include ''[[Suminia]],'' which is thought to have been a climbing form.

===Gorgonopsia===
{{Main|Gorgonopsia}}
[[Image:Inostrancevia BW.jpg|right|thumb|200px|''[[Inostrancevia]]'', a [[gorgonopsia]]n]]

Gorgonopsia is an abundant but morphologically homogeneous group of [[saber-toothed predator]]s.

===Therocephalia===
{{Main|Therocephalia}}
[[Image:Moschorhinus_DB.jpg|right|thumb|200px|''[[Moschorhinus]]'', a [[therocephalia]]n]]
It has been suggested that Therocephalia might not be monophyletic, with some species more closely related to cynodonts than others.<ref name=Abdala2008/> However, most studies regard Therocephalia as monophyletic.

===Cynodontia===
{{Main|Cynodontia}}
[[Image:Trucidocynodon_riograndensis.jpg|right|thumb|200px|''[[Trucidocynodon]]'', a non-[[mammal]]ian [[cynodont]]]]
Cynodonts are the most diverse and longest-lived of the therapsid groups, as Cynodontia includes mammals. Cynodonts are the only major therapsid clade to lack a Middle Permian fossil record, with the earliest-known cynodont being ''[[Charassognathus]]'' from the [[Wuchiapingian]] age of the Late Permian. Non-mammalian cynodonts include both carnivorous and herbivorous forms.