Dicynodon

Dicynodon (from Ancient Greek δίς "two" and κυνόδους "canine teeth", often translated to "two canine-teeth" or "two dog-teeth") is a genus of dicynodont therapsid that lived in southern and eastern Africa during the Late Permian epoch. It is the namesake for the Dicynodontia, being the first genus named and recognised from the group by palaeontologist Richard Owen in 1845, and embodies many of their typical characteristics. It was a herbivore, with a tortoise-like beak and was almost entirely toothless, except for the pair of prominent canine tusks that gave it its name.

Over a hundred species of Dicynodon have been named and placed under Dicynodon since 1845, and the genus was for a long time treated as a wastebasket taxon. A study in 2011 revised every species referred to Dicynodon, and concluded that the only valid species were the type species D. lacerticeps and its close relative D. huenei. The remaining species were either dubious (nomina dubia), referrable to unrelated valid genera, or valid species but representing a paraphyletic grouping, or evolutionary grade, of Permian dicynodontoids (a subclade of dicynodonts that includes Dicynodon, Lystrosaurus, and other closely related Triassic dicynodonts). These species were elevated to their own genera, reviving many names previously synonymous with Dicynodon and establishing several new ones. A 2019 study named another new species of Dicynodon from Tanzania, D. angielczyki. The same study, however, simultaneously transferred D. huenei to the genus Daptocephalus, thus still leaving Dicynodon with only two species.