ammonites
Scinocephalus quadrihastatus Ross, Jr. 1953 (trilobite)

Trilobita - Asaphida

Full reference: R. J. Ross, Jr. 1953. Additional Garden City (Early Ordovician) trilobites. Journal of Paleontology 27(5):633-646

Belongs to Scinocephalus according to R. J. Ross 1953

Sister taxon: Scinocephalus solitecti

Type specimen: YPM 18768, a pygidium. Its type locality is Locality 6, Hillyard's Canyon, recollection of middle "G(2)" zone, which is in a Tulean shallow subtidal horizon in the Garden City Formation of Idaho.

Ecology: fast-moving low-level epifaunal deposit feeder