| Autor: |
Kim KS; Department of Science Education, Chinju National University of Education, Shinan-dong, Jinju, Kyungnam, 52673, South Korea., Lockley MG; Dinosaur Trackers Research Group, University of Colorado Denver, P.O. Box 173364, Denver, CO, 80217-3364, USA. Martin.Lockley@UCDenver.edu., Lim JD; Restoration Technology Division, National Research Institute of Cultural Heritage, 132, Munji-ro Yuseong-gu, Daejon, 34122, South Korea., Bae SM; Institute of Korea Geoheritage, Chinju National University of Education, Shinan-dong, Jinju, Kyungnam, 52673, South Korea., Romilio A; School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Qld, 4072, Australia. |
| Abstrakt: |
Large well-preserved crocodylomorph tracks from the Lower Cretaceous (? Aptian) Jinju Formation of South Korea, represent the well-known crocodylomorph ichnogenus Batrachopus. The Korean sample includes multiple, narrow-gauge, pes-only trackways with footprint lengths (FL) 18-24 cm, indicating trackmaker body lengths up to ~3.0 m. Surprisingly, the consistent absence of manus tracks in trackways, with well-preserved digital pad and skin traces, argues for bipedal trackmakers, here assigned to Batrachopus grandis ichnosp. nov. No definitive evidence, either from pes-on-manus overprinting or poor track preservation, suggests the trackways where made by quadrupeds that only appear bipedal. This interpretation helps solve previous confusion over interpretation of enigmatic tracks of bipeds from younger (? Albian) Haman Formation sites by showing they are not pterosaurian as previously inferred. Rather, they support the strong consensus that pterosaurs were obligate quadrupeds, not bipeds. Lower Jurassic Batrachopus with foot lengths (FL) in the 2-8 cm range, and Cretaceous Crocodylopodus (FL up to ~9.0 cm) known only from Korea and Spain registered narrow gauge trackways indicating semi-terrestrial/terrestrial quadrupedal gaits. Both ichnogenera, from ichnofamily Batrachopodidae, have been attributed to Protosuchus-like semi-terrestrial crocodylomorphs. The occurrence of bipedal B. grandis ichnosp. nov. is evidence of such adaptations in the Korean Cretaceous. |
