Phorcys dubei

Phorcys is an extinct genus of gorgonopsian (predatory therapsids, related to modern mammals) that lived during the Middle Permian period (Guadalupian) of what is now South Africa. It is known from two specimens, both portions from the back of the skull, that were described and named in 2022 as a new genus and species P. dubei by Christian Kammerer and Bruce Rubidge. The generic name is from Phorcys of Greek mythology, the father of the Gorgons from which the gorgonopsians are named after, and refers to its status as one of the oldest representatives of the group in the fossil record. Phorcys was recovered from the lowest strata of the Tapinocephalus Assemblage Zone (AZ) of the Beaufort Group, making it one of the oldest known gorgonopsians in the fossil record—second only to fragmentary remains of an indeterminate gorgonopsian from the older underlying Eodicynodon Assemblage Zone.

Phorcys was also unexpectedly large for an early gorgonopsian with a total skull length estimated at ~30 cm (12 in), comparable to in size to later gorgonopsians and notably larger than the similarly aged Eriphostoma with skull lengths of only ~10–15 cm (3.9–5.9 in). This contradicts prior suggestions that gorgonopsians only achieved larger sizes, and associated top predator status, following the extinction of dinocephalians and large therocephalian therapsids in the Late Permian. Indeed, Phorcys was comparable in size to a contemporary specimen of a scylacosaurid therocephalian with a skull estimated to be ~21 centimetres (8.3 in) long, and even to the slightly older anteosaur Australosyodon (skull length ~26 cm (10 in)). Phorcys and other gorgonopsians may then have been top predators in some Middle Permian assemblages.