Rhynchonellata - Spiriferida - Spiriferidae

Alternative combination: Spirifer occiduus

Full reference: W. Sadlick. 1960. New name for Spirifer occidentalis (Girty) and its geologic history. Journal of Paleontology 34:1210-1214

Belongs to Anthracospirifer according to Lane 1964

Sister taxa: Anthracospirifer arcoensis, Anthracospirifer birdspringensis, Anthracospirifer curvilateralis, Anthracospirifer leidyi, Anthracospirifer oliveirai, Anthracospirifer shawi, Plicatocyrtia zitteli

Ecology: stationary epifaunal suspension feeder