New information on the postcranial skeleton of the Thalassodrominae (Pterosauria,Pterodactyloidea, Tapejaridae)

The clade Tapejaridae is composed by pterosaurs commonly found in fossiliferous deposits in northeastern Brazil. It is constituted by two less inclusive clades: the smaller-bodied Tapejarinae and the larger Thalassodrominae. Here we describe the specimen MN 6566-V, from the Lower Cretaceous Romualdo Formation of the Araripe Basin, Brazil. The specimen is overall well preserved tridimensionally, and consists of three posterior cervical vertebrae, incomplete right and left scapulocoracoids, and the proximal portion of a right humerus. Comparisons to specimens described in the literature enable its identification as a thalassodromine, whose postcranial material is still poorly known despite the large amount of pterosaurs known from this unit.     

On wing disparity and morphological variation of the Santana Group pterosaurs

Pterosaurs were widely spread throughout the Mesozoic Era, populating the whole world. Among this great diversity, two groups are commonly found in Brazil: the Anhangueridae and Tapejaridae. These can be mainly identified by cranial synapomorphies. However, because of the fragility of the pterosaur skeleton and rarity of the fossilisation process, the fossils found are usually incomplete, which hampers a proper taxonomic identification of the specimens. The specific proportions of these two groups of pterosaurs were obtained from bibliographic data and measurements of specimens. Eight Anhangueridae-like and seven Tapejaridae were used: Anhanguera piscator, Anhanguera santanae, Anhanguera spielbergi, Araripesaurus castilhoi, Barbosania gracilisrostris and three Anhangueridae sp. indet.; Sinopterus dongi, Tapejara wellnhoferi and five Tapejaridae sp. indet. We find that proportions of the humerus, wing metacarpal, first phalanx of the wing digit, femur and tibia are sufficient to identify partial remains of Araripe pterosaurs. A principal component analysis shows that each clade has different, non-overlapping scores in the studied ratios and these can be used with precision. Specific bone ratios for fast identification of anhanguerids and tapejarids are given, opening a broader way to diagnostic fragmentary bones.