Revision of the Early Jurassic arthropod trackways Camurichnus and Hamipes.

The ichnogenera Camurichnus and Hamipes have been reevaluated based on examination of their type specimens, and their geographic and stratigraphic ranges determined based on a review of the literature. The characteristics used to distinguish Camurichnus (originally erected as Sagittarius) and its included ichnospecies alternans, have been observed in Bifurculapes laqueatus and therefore Camurichnus alternans is considered a junior subjective synonym of B. laqueatus herein. Hamipes is a distinct ichnogenus that can be differentiated from similar ichnotaxa by the number, shape, and arrangement of the tracks. Cretaceous trackways from Spain that were attributed to Hamipes belong to Bifurculapes. Additionally, the species H. molassicus is moved to the ichnogenus Conopsoides. Since the only other occurrence of Hamipes was the type specimen, the ichnogenus is again known only from the Early Jurassic of Massachusetts, U.S.A. The ichnotaxonomic reassignment, however, extends the geographic and stratigraphic range of Bifurculapes to the Cretaceous of Europe. [ABSTRACT FROM AUTHOR]