Articulated bone sets of manus and pedes of Camarasaurus (Sauropoda, Dinosauria)

Skeletons of sauropods are rarely found with fore and hind feet, and until now, only one specimen of this clade has been reported with all four autopodia preserved complete and articulated. This makes interpretations on their locomotion difficult and proper assignments of footprints to genus- or even species-level taxa are generally impossible. Camarasaurus SMA 0002 from the Upper Jurassic Morrison Formation at Howe Ranch in the vicinity of Shell (Wyoming, USA) is the first sauropod with completely preserved and articulated osteological remains of all feet in addition to autopodial skin impressions. We describe in detail the morphology of the SMA 0002 autopodial bones and integumentary impressions, and draw comparisons with the published data on Camarasaurus and other sauropod manus and pedes. Our reconstruction orients the lateral side of the manus claw such that it faces the ground and possibly even contacts it distally. A 3D reconstruction of the autopodia of SMA 0002 yields new insights into the still debated relationship of footprint lengths to hip height in sauropods, and indicates that it might be variable among genera. Furthermore, manual and pedal morphology and the 3D model yield crucial information about the expected footprint shape of Camarasaurus. The recovered characteristics of the footprint do not possess a set of features to be confidently referred to a known ichnospecies.