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Cistecephalidae
Cistecephalidae is an extinct family of dicynodont therapsids from the Late Permian of South Africa, India and Zambia. It includes the genera Cistecephalus, Cistecephaloides, and Kawingasaurus.[1] Cistecephalids are thought to have had a fossorial or burrowing lifestyle, with adaptations such as broad skulls, strong forelimbs, and squat bodies. A similar group of dicynodonts called the pylaecephalids were also fossorial, although to a lesser extent than cistecephalids.[2] Cistecephalids showed a high level of endemism, with each of the five known species unique to a single region.[3] DescriptionCistecephalids were small dicynodonts. Most species, with the exception of Kembawacela, lacked tusks, but sexually dimorphic supraorbital ridges were present.[3][4] Cistecephalids had boxy, broad skulls with relatively laterally directed temporal openings, a result of a considerably broadened intertemporal region. Sauroscaptor, the most basal genus of the family, had a less extreme broadening of the intratemporal region than in other members of the family.[3] In the derived genera Cistecephaloides and Kawingasaurus, the intratemporal portion of the skull was broader than the skull was long. Cistecephalids also had a relatively posteriorly positioned pineal foramen, which in Kembawacela and Sauroscaptor was displaced all the way to the posterior margin of the skull. They also had anteriorly directed orbits; they may have had binocular vision, which may have been an adaptation for nocturnality or an insectivorous lifestyle.[4] ClassificationThe Cistecephalidae contains five named genera each with one species. It is a member of the Dicynodont clade Emydopoidea. Phylogeny following Kammerer et al. 2016:[1][3] References
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