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.

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.

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.

[6] Collectively, the preserved portions of Phorcys make up the rear of the skull behind the eyes, including the postorbital bar, zygomatic arch, the occiput, and much of the basicranium.

Although the roof of the skull has been narrowed by erosion, the area between the two temporal fenestra (the intratemporal region) is inferred to have been broad and flat like other gorgonopsians from a broken edge still attached to the back of the postorbital, revealing its true extent.

The occiput also sports a prominent nuchal crest running vertically down the centre and widening from the skull roof down to the circular foramen magnum (the opening for the spinal cord, bordered by the occipital condyle beneath).

It sports a pair of knob-like protuberances at the back and inner margins of the "basal tubera", ovoid projections of bone that run from the basiccopital and inwards on to the fused parabasisphenoid in front.

The parabasisphenoid itself is typical of gorgonopsians, sporting the characteristic tall, thin, vertical blade of bone on the narrow cultriform process that extends forwards down the middle of the palate.

However, Kammerer and Rubidge considered this result preliminary due to the fragmentary nature of the known material, and noted that this position in the tree was weakly supported with only one coded characteristic (the straight orientation of the subtemporal zygoma) uniting it with other African gorgonopsians in this analysis (a trait that is itself variable in this clade).

In Phorcys, this bone has only slight variation along its bottom margin, unlike the notable semi-circular blades of the Russian gorgonopsians but very comparable to those in the African clade.

Two other therapsid genera are known only from these units, the predatory burnietamorph Pachydectes and the herbivorous early dicynodont Lanthanostegus, an unusual genus with markedly forward-facing eye sockets.

It is possible then that Phorcys was the top predator in this assemblage, in contrast to therapsid faunas in the upper Tapinocephalus AZ where therocephalians and the even larger anteosaurs dominated.

[2] The presence of a relatively large-bodied early gorgonopsian like Phorcys so low in the Tapinocephalus AZ complicates previously proposed narratives for the ecological evolution of predatory therapsids.

Prior to its discovery, gorgonopsians from older therapsid faunas were small—such as Viatkogorgon and Nochnitsa from Russia and the African Eriphostoma—and were in low abundance, while the largest and most diverse predators were either large therocephalians (namely scylacosaurids and lycosuchids) or giant anteosaurs.

[2] It remains unclear why similarly large gorgonopsians appear to be absent from later Middle Permian faunas such as in the upper Tapinocephalus AZ.