The fossil remains (skull and postcranial elements) of Tapinocephalus are known from the Lower, Middle, and Upper part of the Tapinocephalus Assemblage Zone ( Capitanian age) of the Lower Beaufort Beds of the South African Karoo. Only the type species, T. atherstonei is now considered valid for this genus.
In life, these animals were over 3 metres (10 ft) in length and massed around 1.5 to 2 tonnes (3,300 to 4,400 lb), making them among the largest animals of their time.
Tapinocephalus atherstonei is the only species of this genus. It is known from a number of skulls and postcranial bones. The skull is large with a heavily pachyostotic skull roof, a massive bony frontals and a short weak Moschops-like snout. Taurops is a synonym. This successful animal survived right until the end of the Tapinocephalus zone. Phocosaurus megischion differs from Tapinocephalus only in that the transition from the frontals to the snout is not abrupt. In view of the fact that it too continues until the upper Tapinocephalus zone.