Friday, September 23, 2016

Forfexopterus jeholensis: a new Archaeopterodactyloid Pterosaur From Cretaceous China


Jiang et al


Eleven species of archaeopterodactyloid pterosaurs have been reported in China, mostly from the Yixian Formation of western Liaoning. The first uncontroversial archaeopterodactyloid from the Jiufotang Formation is described here. A new genus and species, Forfexopterus jeholensis, is erected on the basis of a unique combination of characters and one autapomorphy: the first wing phalanx is shorter than the second, but longer than the third. The sternum of Forfexopterus is nearly complete and provides the first incontrovertible evidence about the position of sternocoracoid articulations in the Archaeopterodactyloidea. A preliminary geometric morphometric analysis of sterna was carried out with data from 17 species of Pterodactylomorpha. The results document the variation in the shape of the sternum, including the length of the cristospine, the shapes of the lateral, posterior, and anterior margins, and the constriction and expansion of the cristospine. These characters can be used to compare sterna in different pterosaur taxa.

No comments: