Pterosaurs are represented in China by five genera and some isolated bones ranging in age from the Middle Jurassic to the Late Cretaceous period. Four of these genera belong to the derived monophyletic subgroup Pterodactyloidea; only the Middle Jurassic Angustinaripterus from Dashanpu, Sichuan, is a non-pterodactyloid (traditionally `rhamphorhynchoids', a paraphyletic taxon). Two further pterosaurs (Fig. 1) from the Chaomidianzi Formation of the Beipiao area, western Liaoning Province, occur in the Liaoning beds, several metres higher than the compsognathid coelurosaur Sinosauropteryx and the basal bird Confuciusornis. Our analysis of these two fossils and other components of the fauna suggest a Late Jurassic biostratigraphic age for the Liaoning beds, which are important in the study of avian origins.