Phorcys is an extinct genus of gorgonopsian (predatory therapsids, the group including 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. 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—after the fragmentary remains of an indeterminate specimen from the older underlying Eodicynodon Assemblage Zone and an indeterminate gorgonopsian from the Spanish island of Mallorca, western Mediterranean. 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. Phorcys is unexpectedly large for an early gorgonopsian with a total skull length estimated at ~30 cm (12 in), comparable in size to later gorgonopsians and notably larger than the similarly aged Eriphostoma (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. In 2026, the discovery of Jirahgorgon, a similar gorgonopsian contemporary with Phorcys, suggests that these genera were part of an early radiation of large representatives of this group during the middle Permian that showed traits convergent with later larger forms. This early subgroup of large gorgonopsians was thus named as the family Phorcyidae.
Discovery and naming Only two specimens of Phorcys are known, each consisting of weathered partial skulls broken off before the snout. Both specimens were collected from a locality near Delportsrivier, a farm in Jansenville of Eastern Cape Province, South Africa, and are catalogued as BP/1/5850 and BP/1/5851 by the Evolutionary Studies Institute of the University of the Witwatersrand, where they are stored. These specimens were initially reported on in 1995 by palaeontologist Bruce S. Rubidge, however they would not be described and named as a new genus and species, Phorcys dubei, until 2022 by Rubidge and fellow palaeontologist Christian F. Kammerer. The two specimens were prepared by Mr. Charlton Dube (who himself collected BP/1/5850), and the specific name dubei honours his contribution and commends his skills at fossil preparation. The generic name Phorcys is after Phorcys of ancient Greek mythology, a primordial god and the father of the Gorgons. The name alludes to its status as one of the earliest known gorgonopsians, the group itself being named after the mythological Gorgons with many genera including "gorgon" in their own names. Although both specimens are weathered and damaged, BP/1/5851 is considerably more complete and so was designated the holotype specimen by Kammerer and Rubidge. It preserves most of the skull from the occiput (the back face of the skull) up to the orbits, including the basicranium (the floor of the skull beneath the braincase), an eroded upper surface preserving the intact preparietal and portions of the surrounding frontals and parietal bones, with a broken left zygomatic arch and a left palatine displaced into the left orbit, the only known bone from the front half of the skull. The paratype is less complete and more badly weathered, consisting mostly of a partial occiput with associated parts of the skull roof and the basicranium (as well as other unidentified bone fragments). The locality where both specimens were recovered belongs to the eastern exposures of the Abrahamskraal Formation (of which historically were labelled the Koonap Formation), the lowest (and so oldest) geological formation in the fossiliferous Permo-Triassic aged Beaufort Group of the Karoo Basin. The layers of the Abrahamskraal Formation near Jansenville are typically correlated to the lower Tapinocephalus Assemblage Zone (AZ) fauna. However, due to the unique faunal assemblage known from these localities that are seemingly absent from the rest of the Tapinocephalus AZ (including Phorcys), it has been suggested they may represent a distinct faunal assemblage between the younger Tapinocephalus AZ and the older underlying Eodicynodon Assemblage Zone. This biostratigraphic position corresponds to a Middle Permian (or Guadalupian) age, dating to somewhere within the Wordian to Capitanian stages. At the time of its description, Phorcys represented one of the oldest known gorgonopsians worldwide, second only to an indeterminate and fragmentary specimen, NMQR 2982, discovered in the underlying Eodicynodon AZ and also described by Kammerer and Rubidge in the same article as Phorcys. This specimen only consists of a pair of jaw tips and lacks any characteristics diagnosable to the genus or species level, and so Kammerer and Rubidge referred NMQR 2982 to Gorgonopsia indet (although they acknowledged the possibility it may be conspecific with Phorcys, lack of overlapping material makes this impossible to determine). In 2024, an ever older gorgonopsian was described Spanish island of Mallorca, western Mediterranean, and dated to at minimum the early Wordian, if not the older Roadian or even Cisuralian. However, it too is indeterminate and Phorcys remains the oldest named gorgonopsian.
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