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Kawingasaurus is an extinct genus of dicynodont therapsid from the Late Permian Usili Formation of Tanzania. It is a member of the family Cistecephalidae, and like other cistecephalids it is thought to have been fossorial. It is a member of the family Cistecephalidae. Cistephalidae includes genera Cisteceohalus, Cistecephaloides and Kawingasaurus. Greek for meaning “lizard” appears as a suffix denoting a reptilian origin. Living between 254.17 and 259.9 million years ago in the Lopingian and believed to have the first and last recorded appearance in this time period. It lived in deep burrows as a suggested by most burrowing from evaluation of cranial sutures, vestibule inflation and enlarged stapes foot plates which are thought to be functionally correlated with bone-conduction hearing; all observed in fossorial vertebrates which use seismic signals as communication.
In 1936, seven skulls, parts of the vertebrae, a mandible, ribs and parts of the girdles were excavated by German geologist and his wife Maria Nowack on an expedition in the Ruhuhu area of Southwest Tanzania. The fossils were preserved as a part of Nowack's collection in the Institut und Museum fur Geologic and Paläontologie der Universitat Tubingen (GPIT No. U 31). Later, in 1972 CoxCox CB. 1972. A new digging dicynodont from the Upper Permian of the Tanzania. In: KA Josey, TS Kemp, editors. Studies in Vertebrate Evolution. Edinburgh: Oliver and Boyd. pp 173– 189. investigated the fossils and found further differences between Cistephalus and the excavated skulls. A tapering shape of the skull in lateral and dorsal view, slenderness of the zygomatic arches, and anterior extension of the squamosal to meet the maxilla led to Cox establishing the new genus and species, since Owen's initial description of the group in 1876, K. fossilis due to significant evidence of distinct differences from Cistecephalus.
Underground fossorial animals are sensitive to low-frequency sound and have modifications to their auditory components compared to terrestrial species. The volume of the vestibule relative to the size of K. fossilis proved to be very inflated at 182.00 mm^3 compared to other nonmammalian . According to Cox (1962) and Olsen (1944), the vestibule of the inner ear for “typical anomodonts us described as elongated and slender whereas the vestibule of the inner ear found in Kawingasaurus is extremely inflated with an ellipsoidal shape. The inner ears occupy most of the space of the caudal region of the skull. It was also found that Kawingasaurus has enlarged stapes footplates (measured at 13.91 mm^2) thought to be correlated with bone-conduction hearing observed in fossorial . The triangular head as well as spatulate snout was likely used for digging and seismic signal detection by tapping against tunnel walls for perception of sound. The ventrolateral orientated stapes are thought to better transmit seismic sound from the ground to the fenestra vestibuli than horizontal orientated stapes. Due to a low sound pressure level transformer ratio of 2-3, Kawingasaurus is thought to have seismic sensitivity of the middle ear and a reduced sensitivity to sounds that travel airborne. The quadrate-quadratojugal complex, a thin plate-like bone, transmits sound from the articular to the stapes via minor vibrations of the quadrate process. The ventral parts of the quadrate as well as the quadratojugal are fused to a single unit. The quadrate of K. fossilis is similar to other .
The otic capsule also known as the bony housing of the inner ear of K. fossilis is inflated due to vestibule inflation. The external shape of the otic capsules is reliant on the shape of the vestibule as well as the anterior semicircular canals and ampullae. The otic capsules have significance due to sound transmission mechanisms via the snout, skull roof and otic capsules. On the right side of a preserved mandible, the remains of a small reflected lamina suggests that it covered parts of the recessus mandibularis serving as a sound receiving component. As in other nonmammalian synapsids, the mandible and jaw articulation found in Kawingasarus likely served for both hearing and feeding.
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