Trilobita - Ptychopariida - Ptychopariidae

Full reference: C. E. Resser. 1939. The Spence Shale and its fauna. Smithsonian Miscellaneous Collections 97(12):1-29

Belongs to Spencia according to C. E. Resser 1939

Sister taxa: Spencia typicalis, Stauroholcus typicalis

Type specimen: USNM 96536, a cephalon/head (cranidium)

Ecology: fast-moving low-level epifaunal carnivore