Two anurognathid pterosaur specimens from the Yanliao Biota and a new interpretation of anurognathid skulls

Anurognathids are a clade of small, early-diverging non-pterodactyloid pterosaurs distributed across Eurasia from the Middle Jurassic to the Early Cretaceous. Their defining characteristic is a short and broad skull, a morphology distinct from all other pterosaur clades. Due to limited preservation, the cranial anatomy of this group has long been difficult to understand in detail. In this study, we provide a detailed description of two anurognathid specimens from the Tiaojishan Formation of the Yanliao Biota. The relatively well-preserved skull of one specimen was reconstructed through computed tomographic scanning. This reveals a unique skull element, possibly functionally analogous to the supraorbital bone of varanid lizards. The CT reconstruction offers new insights into the anurognathid skull. Based on these findings, we revised the skulls of previously described taxa, ultimately integrating them into a new reconstruction for this clade. We present a detailed comparative analysis and discussion of the postcranial osteology within Anurognathidae.