A review of vertebrate faunas from the Gyeongsang Supergroup (Cretaceous) in South Korea

The Early Cretaceous is rapidly being recognized as a crucial time in the origin and dispersal of living vertebrate groups. Cretaceous trackways in Korea are among the most abundant in the world and include the smallest sauropod tracks known, plus four avian ichnotaxa, one of which is the earliest record of a bird with webbed feet. Body fossils and egg shells are less well known, however, and have been reported mainly in Korean journals. An increase in the rate of discovery of vertebrate fossils in recent years has resulted in documentation of 38 localities from the entirely fluvio-lacustrine Gyeongsang Supergroup (Hauterivian to Cenomanian) in Korea. Specimens include fish, turtle, crocodilian, pterosaur, and dinosaur bones, and dinosaur eggs in nests, as well as dinosaur, bird, and pterosaur footprints. Scattered bones have been collected in road cuts, quarries, stream beds, and coastal exposures, but localities have yet to be systematically explored and excavated. Nevertheless, very recent finds of articulated fish skeletons and dinosaur egg nests indicate that further exploration may be expected to yield better preserved, more fully associated specimens of these and additional taxa. This would provide further important data for our understanding of this pivotal period in vertebrate evolution.