DE GALHO EM GALHO — LAGERPETIDAE & A ORIGEM DOS PTEROSSAUROS

Abstract

Leaping from branch to branch - Lagerpetidae and the origin of pterosaurs. Pterosaurs are a group of extinct flying reptiles with emergence in the Triassic and great radiation in the Jurassic and Cretaceous, being the first vertebrates to develop active flight. Since the first pterosaurs already show morphologic patterns that are typical for the clade, there is a substantial gap between the first preserved pterosaurs in the fossil record and their closest relatives. Here, we discuss different phylogenetics proposals presented through decades, being the Dinosauromorpha–Pterosauromorpha Hypothesis the most usually recovered. Even considering this hypothesis, however, the morphological gap persists. Thus, we discuss how the knowledge about Lagerpetidae has helped to elucidate the origin of pterosaurs, since recent works indicates that the group would be nested inside the Pterosauromorpha. Lagerpetidae is a group of small reptiles found in the Upper Triassic of North America, Brazil, Argentina and Madagascar, with the Carnian record thus far restricted to the South hemisphere, and with the first records for North America being Norian in age. Recent discoveries point to the presence of insectivorous dentition among Lagerpetidae, as it happens in Triassic pterosaurs. Thus, insectivory can be assigned as an ancestral diet in Pterosauromorpha. This diet is assigned as a possible driving force to the evolution of flight in Pterosauria. Keywords: Pterosauria, Lagerpetidae, Ornithodira, Triassic.