Cynognathia

Cynognathia ("dog jaw") is one of two major clades of cynodonts, the other being Probainognathia. Cynognathians included the large carnivorous genus Cynognathus and the herbivorous or omnivorous gomphodonts such as traversodontids. Cynognathians can be identified by several synapomorphies including a very deep zygomatic arch that extends above the middle of the orbit.

Cynognathians Temporal range: Early to Late Triassic, 251–208.5 Ma PreꞒ Ꞓ O S D C P T J K Pg N
Skull of the carnivorous cynognathian Cynognathus crateronotus
Skull of Exaeretodon a herbivorous traversodontid
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Clade:	Synapsida
Clade:	Therapsida
Clade:	Cynodontia
Clade:	Eucynodontia
Clade:	†Cynognathia Hopson and Barghusen, 1986
Subgroups
†Cynognathus †Gomphodontia †Diademodontidae †Neogomphodontia Hendrickx et al., 2020[1] †Trirachodontidae †Traversodontidae

Cynognathian fossils are currently known from Africa, Antarctica, Asia, Europe, North America and South America.

Taxonomy

• Suborder Cynodontia
  • Infraorder Eucynodontia
    • (unranked) Cynognathia
      • Family Cynognathidae
        • Cynognathus
      • (unranked) Gomphodontia
        • Family Diademodontidae
          • Diademodon
          • Titanogomphodon
        • (unranked) Neogomphodontia
          • Family Trirachodontidae
            • Subfamily Trirachodontinae
              • Langbergia
              • Trirachodon
            • Subfamily Sinognathinae
              • Beishanodon
              • Sinognathus
              • Cricodon
          • Family Traversodontidae
            • Etjoia
            • Nanogomphodon
            • Scalenodon
            • Subfamily Traversodontinae
              • Traversodon
              • Luangwa
            • Unnamed clade
              • Andescynodon
              • Pascualgnathus
              • Mandagomphodon
              • Subfamily Massetognathinae
                • Dadadon
                • Massetognathus
                • Santacruzodon
              • Subfamily Arctotraversodontinae
                • Arctotraversodon
                • Boreogomphodon
                • Plinthogomphodon
                • Habayia
                • Maubeugia
                • Microscalenodon
                • Mandagomphodon
                • Rosieria
              • Subfamily Gomphodontosuchinae
                • Gomphodontosuchus
                • Menadon
                • Protuberum
                • Ruberodon
                • Scalenodontoides
                • Exaeretodon
                • Siriusgnathus

Phylogeny

Cynognathians in a cladogram after Stefanello et al. (2023):^[2]

Eucynodontia	Cynognathia Cynognathus crateronotus Gomphodontia Diademodon tetragonus Langbergia modisei Trirachodon berryi Sinognathus gracilis Traversodontidae Pascualgnathus polanskii Luangwa drysdalli Scalenodon angustifrons Mandagomphodon hirschoni Massetognathus pascuali Exaeretodon argentinus Probainognathia

See also

• Evolution of mammals