LAUSR

Abstract The Tapejaridae compose a pterodactyloid clade of pterosaurs that is one of the most abundant flying reptiles in the deposits of the Early Cretaceous Crato Formation from the Araripe Basin, northeast Brazil. Until now, only one tapejarid specimen from this locality shows a relatively complete vertebral column. Here we describe a second specimen (LPU 1535) and compare it with more complete tapejarine tapejarids from western Liaoning (China). Among the most striking differences are the absence of a notarium in the Chinese material and the lesser number of dorsal elements in the Brazilian specimens, the latter perhaps being an evolutionary trend in the Tapejarinae. The new material confirms that the number of dorsal elements forming the notarium and taking part in the synsacrum increase during ontogeny. Some member of the Tapejaridae might share the dorsal part of the postacetabular process of ilia extending medially and fusing to the neural spines of the sacral vertebrae, a feature previously observed in the pteranodontid pterodactyloid Pteranodon.