Numerous footprints of dinosaurs, pterosaurs and birds, together with arthropod tracks,
have been discovered in the upper Cretaceous Uhangri Formation which crops out along the south-western
coastline of South Korea. This ichnofauna contains the first pterosaur tracks reported from
Asia. The digitigrade tridactyl manus impressions exhibit features of a typical pterosaur hand print.
The pes impressions, however, show features that are different from pterosaur footprints reported previously:
there is no visible trace of impressions of individual digits, and the toes are triangular or
rounded in shape distally without distinct claw impressions. As these features clearly distinguish the
Uhangri tracks from Pteraichnus and Purbeckopus, we assign them to a new genus, Haenamichnus
which accommodates the new ichnospecies, Haenamichnus uhangriensis. The prints are five to six times
larger than those of Pteraichnus, and are currently the largest pterosaur ichnites known. They show
virtually no trace of the 5th phalange of the pes, indicating that they were made by pterodactyloids;
moreover, features of the tracks suggest that they can be attributed to azhdarchids, the commonest
pterosaur of the Late Cretaceous. The longest pterosaur trackway yet known from any track site
(length 7.3 m) and consisting of 14 pairs of foot impressions, was also found in the Uhangri
Formation and suggests that azhdarchids, at least, were competent terrestrial locomotors. The fossil
track site at Uhangri represents the first occurrence of the tracks of pterosaurs, dinosaurs and web-footed
birds all on the same level. This demonstrates that pterosaurs and birds visited the same habitat,
but the large size disparity suggests that they occupied different ecological niches.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.