New Sauropod Tracks (Brontopodus pentadactylus ichnosp. nov.) from the Early Cretaceous Haman Formation of Jinju Area, Korea: Implications for Sauropods Manus Morphology

Abstract

New sauropod tracks are described herein as Brontopodus pentadactylus ichnosp. nov. from the Early Cretaceous Haman Formation of Jinju area, Korea. B. pentadactylus is characterized by a medium gauged trackway with wide pentadactyl manus tracks revealing hitherto unreported morphology. Thus, B. pentadactylus provides new insight into the morphology of the fleshed-out manus of sauropods showing that, unlike most semi-circular manus tracks that lack discrete digit traces, some indicate trackmakers with clearly differentiated, well-defined, and very wide manus digits. Manus tracks sometimes appear as tridactyl impressions that appear outwardly rotated at right angles to the midline of the trackway. This track morphology appears to reflect greater weight distribution on the outer, postero-lateral part of the manus. The pes is elongate, pentadactyl, outwardly rotated, and typical of Brontopodus. The manus pes heteropody ratio is about 1:2. These sauropod tracks are associated with thousands of bird footprints in a lakeshore paleoenvironment.

Keywords:

• Sauropod
• Footprints
• Cretaceous
• Korea

ACKNOWLEDGMENTS

The authors thank M. S. O, S. H. Han, M. R. Park, S. H. Bang, and M. Y. Chung, graduate students in the Department of Earth Science Education, Korea National University of Education, for help in the laboratory and field. We thank Justin Spielmann (New Mexico Museum of Natural History and Science) and Hendrik Klein (Neumarkt, Germany) for their helpful reviews, and we thank Spencer Lucas (New Mexico Museum of Natural History and Science) for his work as guest editor of this issue.