Submitted by PPG Zoologia (zoologia-pg@pucrs.br) on 2018-03-23T11:43:57Z No. of bitstreams: 1 Disserta??o_N?bia_Galvez.pdf: 5495418 bytes, checksum: 922705429c6578b50f11ec700c76b295 (MD5) / Approved for entry into archive by Tatiana Lopes (tatiana.lopes@pucrs.br) on 2018-04-05T13:38:27Z (GMT) No. of bitstreams: 1 Disserta??o_N?bia_Galvez.pdf: 5495418 bytes, checksum: 922705429c6578b50f11ec700c76b295 (MD5) / Made available in DSpace on 2018-04-05T13:43:07Z (GMT). No. of bitstreams: 1 Disserta??o_N?bia_Galvez.pdf: 5495418 bytes, checksum: 922705429c6578b50f11ec700c76b295 (MD5) Previous issue date: 2017-03-27 / Conselho Nacional de Pesquisa e Desenvolvimento Cient?fico e Tecnol?gico - CNPq / Temnospondyls are early amphibians, with a broad morphological and ecological diversity that inhabited the planet between the Carboniferous and Cretaceous. They represent a grade of fossil species, which are very important for evolution of the continental fauna and, possibly, have a strict relationship with current amphibians (Lissamphibia). In Brazil, the group is well represented in Permo?Triassic sediments, with nine species described so far. In Rio Grande do Sul, two species were recorded in Permian sediments from Rio do Rasto Formation, where the material MCP-4275PV was collected. This specimen is represented by a hemimandible preserved in two portions, roughly 50 cm long, indicating that it was a large animal. Preparation of the specimen, with sediment removal, evidenced important characteristics for the diagnose of the specimen in a less inclusive taxonomic level. The morphological analyses suggests that the specimen belong to Capitosauria group and the phylogenetic analysis (TNT, PAUP; 76 terminals, 271 characters) showed that MCP-4275PV is consistently placed within Capitosauria, a group so far exclusively Triassic in distribution. Therefore, the new specimen is the oldest capitosaur and its record points out to a South American origin to the group. Such results bring evidences that according with other studies about possible dispersion routs through Pangaea, from Gondwana to Laurasia and about the radiation and speciation of the group relative to the Permo?Triassic boundary. / Temnosp?ndilos s?o anf?bios primitivos, com uma grande diversidade morfol?gica e ecol?gica, que habitaram o planeta entre o Carbon?fero e Cret?ceo. Representam um grado de esp?cies f?sseis de grande import?ncia na evolu??o das biotas continentais e muito possivelmente tem uma rela??o estreita com os grupos de anf?bios atuais. No Brasil, o grupo faz parte da importante paleofauna tetr?poda e est? bem representado em sedimentos Permo?Tri?ssicos, contando com nove esp?cies descritas at? o momento. No Rio Grande do Sul, quatro esp?cies s?o registradas em sedimentos permianos da Forma??o Rio do Rasto, onde o material apresentado aqui (MCP-4275PV) foi coletado. O esp?cime ? representado por uma hemimand?bula preservada em duas por??es e possui aproximadamente 50 cm de comprimento, o que indica pertencer a um animal de grande porte. A prepara??o do material, com remo??o de sedimentos, evidenciou caracter?sticas importantes para o diagn?stico do esp?cime em n?vel taxon?mico mais exclusivo. A an?lise morfol?gica mostrou que o esp?cime apresenta caracter?sticas t?picas de Capitosauria e a an?lise filogen?tica (TNT, PAUP; 76 terminais, 271 caracteres) revelou que MCP-4275PV consistentemente surge dentro de Capitosauria, um grupo com distribui??o at? ent?o exclusivamente tri?ssica. MCP-4275PV representa atualmente o capitossaurio mais antigo, posicionando a origem do grupo no Permiano (Guadalupiano) da Am?rica do Sul. Tais resultados trazem evid?ncias que est?o de acordo com outros estudos sobre poss?veis rotas de dispers?o atrav?s do supercontinente Panga, a partir do Gondwana para a Laur?sia e sobre a radia??o e especia??o do grupo em rela??o ao limite Permo-Tri?ssico.