The theropod that wasn't: an ornithopod tracksite from the Helvetiafjellet Formation (Lower Cretaceous) of Boltodden, Svalbard

We re-examine a Lower Cretaceous dinosaur tracksite at Boltodden in the Kvalvågen area, on the east coast of Spitsbergen, Svalbard. The tracks are preserved in the Helvetiafjellet Formation (Barremian). A sedimentological characterization of the site indicates that the tracks formed on a beach/margin of a lake or interdistributary bay, and were preserved by flooding. In addition to the two imprints already known from the site, we describe at least 34 additional, previously unrecognized pes and manus prints, including one trackway. Two pes morphotypes and one manus morphotype are recognized. Given the range of morphological variation and the presence of manus tracks, we reinterpret all the prints as being from an ornithopod rather than a theropod, as previously described. We assign the smaller (morphotype A, pes; morphotype B, manus) to Caririchnium billsarjeanti . The larger (morphotype C, pes) track is assigned to Caririchnium sp., differing in size and interdigital angle from the two described ichnospecies C . burreyi and C . billsarjeanti . The occurrence of a quadrupedal, small to medium-sized ornithopod in Svalbard is puzzling, considering the current palaeogeographical reconstructions and that such dinosaur tracks have mainly been described from Europe but not North America.