Sauropod Trackway Reflecting an Unusual Walking Pattern from the Early Cretaceous of Shandong Province, China

ABSTRACT

The trackway of a quadrupedal dinosaur from the Early Cretaceous (Albian) Qingquan tracksite (Tancheng, Shandong Province) is redescribed, and the trackmaker is identified as a sauropod. The trackway makes a slight turn towards the northwest and is characterized by an extremely narrow gauge pattern and an unusual configuration, i.e., a conspicuous difference between the position of the left and right manus tracks with respect to the position of the preceding pes track. Left manus tracks are located on the inside of the trackway, very close (and sometimes even in connection) to the opposite right pes tracks. So far, the Qingquan trackway is possibly the only extremely narrow-gauge sauropod trackway known from China. However, it is not clear to what extent this extremely narrow gauge pattern is related to the turning or a special behavior, or even linked to an injury (“limping trackway”). We tentatively attribute the Qingquan trackway to cf. Parabrontopodus, even though it has a rather low heteropody that is significantly lower than in Parabrontopodus and not typical for narrow-gauge sauropod trackways, but occurs in the wide-gauge ichnotaxon Brontopodus. Because of this discrepancy, the Qingquan trackway cannot readily be attributed to a more basal sauropod, which is generally considered the producer of narrow-gauge trackways. Therefore, the identification of a distinct sauropod group is not possible presently. The only skeletal remains of sauropods from the Lower Cretaceous of Shandong Province belong to the large titanosauriform, Euhelopus zdanskyi.

KEYWORDS:

• Sauropod track
• Trackway configuration
• Locomotion
• Trackway gauge
• Early Cretaceous
• Tancheng

Acknowledgments

The authors thank Martin G. Lockley (University of Colorado Denver, USA) and Gerard D. Gierliński (Polish Geological Institute, Poland) for their critical comments and suggestions on this paper.

Funding

This research project was supported by the Linshu Land and Resources Bureau, Shangdong Province, China, and the National Natural Science Foundation of China (No. 41272021: Taphonomy of the Cretaceous dinosaur in the jiaozhou-laiyang basin of Shandong Province and its implications of paleoecology and paleogeography).