Reassessment of Faxinalipterus minimus , a purported Triassic pterosaur from southern Brazil with the description of a new taxon

PeerJ

article

Alexander W.A. Kellner¹  Borja Holgado¹  Orlando Grillo¹  Flávio Augusto Pretto³  Leonardo Kerber³  Felipe Lima Pinheiro⁵  Marina Bento Soares¹  Cesar Leandro Schultz⁶  Ricardo Tadeu Lopes⁷  Olga Araújo⁷  Rodrigo Temp Müller³ 

[1] Laboratório de Sistemática e Tafonomia de Vertebrados Fósseis, Setor de Paleovertebrados, Departamento de Geologia e Paleontologia, Museu Nacional, Universidade Federal do Rio de Janeiro;Institut Català de Paleontologia Miquel Crusafont, Universitat Autònoma de Barcelona;Centro de Apoio à Pesquisa Paleontológica da Quarta Colônia, Universidade Federal de Santa Maria;Programa de Pós-Graduação em Biodiversidade Animal, Universidade Federal de Santa Maria;Laboratório de Paleobiologia, Universidade Federal do Pampa;Departamento de Paleontologia e Estratigrafia, Universidade Federal do Rio Grande do Sul;Laboratório de Instrumentação Nuclear, Programa de Engenharia Nuclear, Universidade Federal do Rio de Janeiro

关键词: Archosauria;    Pterosauromorpha;    Triassic;    Santa Maria Supersequence;    Rio Grande do Sul;    Brazil;   

DOI  :  10.7717/peerj.13276

学科分类：社会科学、人文和艺术（综合）

来源: Inra

【 摘 要 】

Faxinalipterus minimus was originally described as a purported pterosaur from the Late Triassic (early Norian) Caturrita Formation of southern Brazil. Its holotype comprises fragmentary postcranial elements, whereas a partial maxilla was referred to the species. The assignment of Faxinalipterus minimus to Pterosauria has been questioned by some studies, but the specimen has never been accessed in detail after its original description. Here we provide a reassessment of Faxinalipterus minimus after additional mechanical preparation of the holotype. Our interpretations on the identity of several bones differ from those of the original description, and we found no support favoring pterosaur affinities for the taxon. The maxilla previously referred to Faxinalipterus minimus is disassociated from this taxon and referred to a new putative pterosauromorph described here from a partial skull and fragmentary postcranial elements. Maehary bonapartei gen. et sp. nov. comes from the same fossiliferous site that yielded Faxinalipterus minimus, but the lack of overlapping bones hampers comparisons between the two taxa. Our phylogenetic analysis places Faxinalipterus minimus within Lagerpetidae and Maehary bonapartei gen. et sp. nov. as the earliest-diverging member of Pterosauromorpha. Furthermore, the peculiar morphology of the new taxon reveals a new dental morphotype for archosaurs, characterized by conical, unserrated crowns, with a pair of apicobasally oriented grooves. These two enigmatic archosaurs expand our knowledge on the Caturrita Formation fauna and reinforce the importance of its beds on the understanding of Late Triassic ecosystems.

【 授权许可】

CC BY