Barasaurus

Abstract: The parareptile Owenetta rubidgei is known from several skulls, all found in Upper Permian sediments of South Africa. The anatomy of a new species of Owenetta, O. kitchingorum, from the Early Triassic is described here on the basis of three nearly complete skeletons. This new species is distinguished from O. rubidgei on the basis of three dental and three cranial features. Postcranial features cannot be used in the diagnosis because the postcranial anatomy of O. rubidgei is unknown. The small parareptile Barasaurus from the Late Permian of Madagascar and Owenetta are united in the clade Owenettidae, as the sister-taxon of Procolophonidae. Controversies surrounding parareptilian phylogeny are discussed as they relate to Owenetta.

Abstract: Recently discovered reptile specimens from the "Eotriassic" deposits of Madagascar (Lower Triassic) are reported, adding valuable information to our knowledge of Malagasy faunas and providing additional data on tetrapod survivorship across the Permian–Triassic (P–T) boundary. Four specimens are attributable to the terrestrial procolophonoid Barasaurus besairiei Piveteau 1955, whereas the remainder are referable to the aquatic younginiform family Tangasauridae, including some individuals identifiable as Hovasaurus boulei Piveteau 1926. These specimens represent the geologically youngest tangasaurid and Barasaurus specimens to be described from Madagascar and suggest that these small reptiles passed unaffected through the end Permian mass extinction event, when ~78% of amniote families disappeared.

Abstract: THE COUNCIL’S RESEARCH COMMITTEE, UNIVERSITY OF THE WITWATERSRAND; NATIONAL RESEARCH FOUNDATION (NRF); The Open Research Programme of the Foundation for Research Development

Abstract: The procolophonid amniote Barasaurus besairiei Piveteau 1955 is fully described and restored for the first time with emphasis placed on the postcranial skeleton, which is only poorly known in most of the other taxa of early amniotes.%%%%The study focuses on testing a hypothesis of relationships, namely whether procolophonids are the sister-group of Testudines as proposed by Reisz & Laurin (1991). The description provides a sound basis for a new phylogenetic study of early amniotes. Using 13 taxa and 68 characters, the analysis indicates that synapsids are the sister-group of all other known amniotes, named Sauropsida. The Sauropsida are divided into Palaeosauropsida and Eusauropsida. Palaeosauropsida comprise Millerettidae as the sister-group of Procolophoniformes. The Procolophoniformes contain Procolophonia and Testudinomorpha as sister-groups. Testudines are the sister-group of Pareiasauria within the Testudinomorpha. Within Procolophonia, the family Owenettidae, including Barasaurus and Owenetta, is the sister-group of the family Procolophonidae. Eusauropsida include captorhinids, Palaeothyris and diapsids.%%%%All of the three major amniote clades have extant taxa: Synapsida – mammals; Palaeosauropsida – turtles; Eusauropsida – diapsids including birds. The terms "Reptilia" and "Parareptilia" are omitted from systematics: Parareptilia for a misleading name and Reptilia in general because of its historical burden.%%%%The new tree is strong in supporting Procolophonia and Testudinomorpha (sister-group of Pareiasauria and Testudines). It is not very firm in establishing eusauropsids and diadectomorphs because they were outside the main focus of the analysis. Mesosauria is the only group of Palaeozoic amniotes not included in this study.