Redescription of the first pterosaur remains from Japan: the largest flying reptile from Asia

Abstract

Pterosaur remains are found in numerous deposits of the world, but most are isolated and fragmentary elements. This is the case of Japan where a small number of specimens from those volant reptiles have been reported. Here, we redescribe the first pterosaur remains from Japan (NSM PV15005) that were found in outcrops of the Upper Cretaceous Yezo Group (Santonian-lower Campanian) in the Mikasa area of Hokkaido. Further preparation of this material revealed several pterosaur bones, including the distal end of a left femur, a non-ungual phalanx and a proximal caudal vertebra. Based on the double-condyle articulation of the caudal element and the main features of the femur, this specimen is referred to a pteranodontid-like pterosaur. Its wingspan is estimated to be around 6.8m, making it the largest pterosaur recorded not only from Japan, but also from Asia so far, indicating that large flying reptiles were widespread worldwide during the Upper Cretaceous.