Dinocephalia Temporal range: Middle Permian, 270–260 Ma |
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Skeleton of Titanophoneus potens, a carnivorous dinocephalian of the Middle Permian | |
Scientific classification | |
Kingdom: | Animalia |
Phylum: | Chordata |
Order: | Therapsida |
Clade: | Eutherapsida |
Suborder: |
†Dinocephalia Seeley, 1895 |
Subgroups | |
see Taxonomy |
see Taxonomy
Dinocephalia is a clade of large-bodied early therapsids that flourished for a brief time in the Middle Permian between 270 and 260 million years ago (Ma), but became extinct leaving no descendants. Dinocephalians included both herbivorous, carnivorous, and omnivorous forms. Many species had thickened skulls with many knobs and bony projections. Dinocephalian fossils are known from Russia, China, Brazil, South Africa, Zimbabwe, and Tanzania.
Apart from the Biarmosuchians and the Eotitanosuchidae, the Dinocephalians are the least advanced therapsids, although still uniquely specialised in their own way. They retain a number of primitive characteristics (e.g. no secondary palate, small dentary) shared with their pelycosaur ancestors, although they are also more advanced in possessing therapsid adaptations like the expansion of the ilium and more erect limbs. They include carnivorous, herbivorous, and omnivorous forms. Some were semi-aquatic, others were fully terrestrial. They were among the largest animals of the Permian period; only the biggest Caseidae and Pareiasauridea rivalling or even exceeding them in size.
Dinocephalians were generally large. The biggest herbivores (Tapinocephalus) and omnivores (Titanosuchus) may have massed up to 2 tonnes (4,400 lb), and were some 4.5 metres (15 ft) long, while the largest carnivores (such as Titanophoneus and Anteosaurus) were at least as long, with heavy skulls 80 centimetres (31 in) long, and overall masses of around a half tonne.