A new caimanine (Crocodylia, Alligatoroidea) species from the Solimoes Formation of Brazil and the phylogeny of Caimaninae

Autor(es)

Souza-Filho, Jonas P. ^[1] ; Souza, Rafael G. ^[2] ; Hsiou, Annie Schmaltz ^[3] ; Riff, Douglas ^[4] ; Guilherme, Edson ^[1] ; Negri, Francisco Ricardo ^[5] ; Cidade, Giovanne M. ^[3]

Afiliação do(s) autor(es)

^[1] Univ Fed Acre, Lab Paleontol, BR-69915900 Rio Branco, Acre - Brazil

^[2] Univ Fed Rio de Janeiro, Museu Nacl, Dept Geol & Paleontol, Lab Sistemat & Tafon Vertebrados Fosseis, BR-20940040 Rio De Janeiro, RJ - Brazil

^[3] Univ Sao Paulo, Fac Filosofia Ciencias & Letras Ribeirao Preto, Dept Biol, Lab Paleontol, BR-14040901 Ribeirao Preto, SP - Brazil

^[4] Univ Fed Uberlandia, Inst Biol, Lab Paleontol, BR-38400902 Uberlandia, MG - Brazil

^[5] Univ Fed Acre, Lab Paleontol, Campus Floresta, BR-69980000 Cruzeiro Do Sul, Acre - Brazil

• Tipo de documento: Artigo Científico
• Fonte: JOURNAL OF VERTEBRATE PALEONTOLOGY; v. 38, n. 5 SEP 3 2018.
• Citações Web of Science: 3

Resumo

The Miocene deposits of South America are notable for their diverse crocodyliform fauna, of which the giant caimanine Purussaurus is a well-known example. This contribution describes a new caimanine, Acresuchus pachytemporalis, gen. et sp. nov., based on an almost complete skull and mandible from the late Miocene Solimoes Formation of the southwestern Brazilian Amazonia. This new taxon is based on a unique combination of characters, of which the presence of an upturned posterolateral margin of the squamosal throughout the entire lateral margin of the bone (a horn'), with a dorsoventral expansion in the posterior portion of the eminence, stands out. We conducted a phylogenetic analysis of Eusuchia, which showed the new taxon as sister to Purussaurus. This placement allows discussion about the evolution of gigantism in the Acresuchus-Purussaurus clade, which reveals several characters that may be related to gigantism. Additionally, Acresuchus was probably a medium-sized generalist caimanine that had an ecological niche similar to the extant Melanosuchus niger. Until now, crocodyliforms that had such niches were unknown from the Solimoes Formation. (AU)

• Processo FAPESP: 11/14080-0 - Os Squamata (Reptilia, Lepidosauria) do Cretáceo e Terciário (Paleogeno/Neogeno) das bacias Bauru, Aiuruoca e Acre: sistemática, evolução e paleoambientes
• Beneficiário: Annie Schmaltz Hsiou
• Modalidade de apoio: Auxílio à Pesquisa - Jovens Pesquisadores
• Processo FAPESP: 13/04516-1 - Revisão Sistemática do gênero Mourasuchus (Alligatoroidea, Caimaninae), um dos crocodilos mais peculiares do mundo
• Beneficiário: Giovanne Mendes Cidade
• Modalidade de apoio: Bolsas no Brasil - Mestrado