out steeply from the centra, and feature sharp keels on the front and back sides. Unlike eutheriodonts, gorgonopsians do not have distinguished lumbar vertebrae. Nonetheless, the dorsals equating to that series are similar to the lumbars of sabre-toothed cats with steeply oriented zygopophases, useful in stabilising the lower back especially when pinning down struggling prey. There are three sacral vertebrae, and the series attached to the pelvis by the first vertebra. The pelvis is reptilian, with separated ilium, ischium, and pubis. The femur is slightly s-shaped, and is short but longer and slenderer than the humerus. For most, the tibia and fibula strongly curve into each other, and the tibia is more robust than the fibula. The joint between the ankle and the heel bones may have been somewhat mobile. The fifth digit for both the hands and feet was not attached to the carpus/tarsus, and instead connected directly to the ulna/heel bone. Taxonomy Fossil bearing sites In 1876, the first gorgonopsian remains were identified in the Beaufort Group of the Karoo Supergroup of South Africa, by the biologist and paleontologist Richard Owen. He classified the fossils as Gorgonops torvus, combining the Greek Gorgon, a mythological beast, with the word (), meaning 'aspect'. In Africa, gorgonopsians have also been found in Karoo outcroppings in the Ruhuhu Valley of Tanzania, the Upper Luangwa Valley of Zambia, and Chiweta, Malawi. Gorgonopsians were first identified in Russia in the 1890s at the Sokolki locality on the Northern Dvina in Siberia under the supervision of Russian palaeontologist Vladimir Prokhorovich Amalitskii. In a posthumous publication, it was described as Inostrancevia alexandri, and it is one of the best known and largest gorgonopsians. Since then, only a few more Russian genera have been described: Pravoslavlevia, Sauroctonus, Viatkogorgon, Suchogorgon, and Nochnitsa. One of the Russian genus named, Leogorgon, is now considered as a nomen dubium. Gorgonopsians are conspicuously absent beyond these 2 areas. In 1979, Chinese palaeontologist Yang Zhongjian described a Chinese gorgonopsian "Wangwusaurus tayuensis" based on teeth from the Late Permian Jiyuan Formation, but in 1981, palaeontologists Denise Sigogneau-Russell and Ai-Lin Sun found the assigned material to be a random assemblage of which only two have even a remote similarity to Gorgonopsia. In 2022, paleontologists Jun Liu and Wan Yiang identified a possible gorgonopsian dating from the Upper Permian in China, although it is only known from dentary remains. In 2003, Indian palaeontologists Sanghamitra Ray and