The first record of pterosaurs from the Lower Cretaceous Hutubei Formation (lower Tugulu Group) of the southern Junggar Basin (NW China) – A glimpse into an unusual ecosystem

Abstract

The Lower Cretaceous Hutubei Formation of the southern Junggar Basin (northwestern China) is characterised by a very low faunal diversity, yielding almost exclusively the sinemydid turtle Wuguia. Here we describe the first pterosaur remains from the Hutubei Formation comprising a complete right ulna and the distal part of a left wing metacarpal. The ulna shares a synapomorphy with the Dsungaripteridae and is morphologically similar to that of the dsungaripterid Dsungaripterus. The wing metacarpal also shares a synapomorphy with the Dsungaripteridae and the more inclusive clade Dsungaripteroidea, and is morphologically nearly indistinguishable from those of the dsungaripterids Dsungaripterus, Lonchognathosaurus and Noripterus. We therefore assign both specimens to the Dsungaripteridae. They represent one of the oldest records of dsungaripterids from the Tugulu Group and one of the few occurrences of pterosaurs from the southern Junggar Basin. Additionally, they shed light on the community structure of a highly unusual ecosystem preserved in the Lower Cretaceous Hutubei Formation, an ecosystem that appears to have persisted for several millions of years in the southern Junggar Basin.