Ptyocephalus yersini Ordovician Trilobite from Utah

Description: This is a trilobite known as Ptyocephalus yersini, an Asaphid from the Subfamily Ptyocephalinae.

Utah (as well as other Western States) is well known for its Cambrian fauna and trilobites in particular. Trilobites from the Ordovician also occur but in far fewer exposures. In Utah, the Fillmore, Garden City, Pononip, Swan Peak, and Wah Wah Formations yield Ordovician trilobites. No trilobites from Utah are known that are younger than the middle Ordovician. This trilobites comes from my own lease in the lower, middle Ordovician Fillmore formation. These trilobites are not commonly offered.