The Gorgonopsians were a distinctive group of Therapsid Reptiles known from the Middle-to-Late Permian. They were exclusively terrestrial, had binocular vision, a Crocodile-like, semi-erect gait, and are interpreted as having been homeothermic (capable of maintaining a constant internal temperature through a mixture of behavioural and metabolic processes), and possibly to have had fur and the ability to sweat. The jaws of Gorgonopsians have been reconstructed to have been able to open to more than 90°, and to have been able to deliver a powerful bite, making them formidable predators. The dentition of Gorgonopsians is particularly interesting, as they had Mammal-like heterodont dentition, with distinctive incisor, canine, and molar teeth, but retained Reptile-like polyphyodont tooth-replacement (i.e., new teeth constantly replacing older, worn, teeth throughout their lives). The canine teeth of Gorgonopsians were greatly enlarged compared to the other teeth, giving them a 'sabre-toothed' gape, and serrated in a similar way to the teeth of predatory Theropod Dinosaurs.
The earliest Gorgonopsians were small Animals, with skulls 10-15 cm in length, found in European Russia. The group split into two clades quite early on, one persisting in European Russia and the other spreading to Africa, where they became a successful and diverse group best known from the Karoo Basin of South Africa. Both groups grew steadily over the remainder of the Permian, with the largest being the Late Permian Inostranceviines, a group of 'Russian' Gorgonopsians which spread into Africa for a second time, the largest of which had skulls 60 cm in length, and are interpeted as having had body-lengths of up to 3.5 m and body masses of around 300 kg.
The Metangula Graben of northern Mozambique has produced a range of Late Permian fossils comparable to those found in the Karoo Basin of South Africa, including pollen, Plants, and Vertebrate Animals, notably Dicynodonts such as Dicynodon angielczyki, Daptocephalus leoniceps, Dicynodontoides/Kingoria, Endothiodon mahalonobisi, and Lystrosaurus. However, despite their importance in the Karoo ecosystems, only fragmentary and unidentifiable Gorgonopsian remains have been described from the Metangula Graben to date.
In a paper published in the Swiss Journal of Palaeontology on 6 March 2025, Zanildo Macungo of the Museu Nacional de Geologia in Maputo, and the Evolutionary Studies Institute at the University of the Witwatersrand, Julien Benoit, also of the Evolutionary Studies Institute at the University of the Witwatersrand, and Ricardo Araújo of the Centro de Recursos e Ambiente & Instituto de Plasmas e Fusão Nuclear at the Universidade de Lisboa, describe a Gorgonopsian specimen from the Metangula Graben of Northern Mozambique.
The described specimen, PPM2018-7Z, was collected along one of the branches leading to the Maluízo River, about 3 km to the northwest of the town of Mepoche in Lago District. This exposure is considered to belong to the K6a2 Member of the K6 Formation, which has produced Therapsid taxa such as Daptocephalus cf. Daptocephalus leoniceps and Dicynodontoides/Kingoria, and is therefore considered to be equivalent to the Daptocephalus Assemblage Zone of the Karoo Basin, making it 254.5–251 million years old.
Specimen PPM2018-7Z is a partial skull which has undergone dorsoventral compression and mediolateral shearing. The skull roof, occiput, and a small portion of the posterior part of the basicranium are preserved, although fractures pass through the parietal-frontal suture and the separation between the occiput from the dorsal half of the foramen magnum. The crushing and fracturing has led to the loss of fine structures such as the nuchal ridge, pila antoticae, and most of the parasphenoid rostrum.
A small portion of the left maxilla is still attached to the skull, with a larger fragment of the right maxilla being found associated with the skull. Also found in association was large, mediolaterally compressed left canine, and a badly preserved cross-section of the right canine. The preserved left canine is 113 mm long and 32 mm wide at the base; the root is not preserved.
Specimen PPM2018-7Z is assigned to the species Inostrancevia africana, on the basis of the presence of rugosity and small foramina on the lateral face of the prefrontal, an orbit larger than the temporal fenestra (11 cm vs. 9 cm, respectively), extreme narrowing of the jugal below the orbit, a far posterior position of the pineal foramen, a reduced contribution of the frontal to the orbital margins, the presence of a deep parietal depression, an anteroposteriorly greatly expanded postorbital bar ventrally, the protrusion of the postfrontal onto the parietal, and the laterally facing temporal bar of the squamosal.
This represents the fourth specimen of Inostrancevia africana described, with two previously described specimens from the Daptocephalus Assemblage Zone of the Karoo Basin in South Africa, and one from the Usili Formation of the Ruhuhu Basin in Tanzania. This distribution is noteworthy because Inostrancevia africana belongs to the Russian clade of the Gorgonopsian group, with all of its close relatives, including the co-generic Inostrancevia alexandri being found exclusively in European Russia.
See also...
