†Phacops iowensis southworthi Stumm 1953 (trilobite)
Artiopoda - Phacopida - Phacopidae
Alternative combination: Phacops southworthi
Full reference: E. C. Stumm. 1953. Trilobites of the Devonian Traverse Group of Michigan. Contributions from the Museum of Paleontology, the University of Michigan 10(6):101-157
Belongs to Phacops iowensis according to E. C. Stumm 1953
See also Wagner 2020
Sister taxa: none
Type specimen: UMMP 24313
Ecology: fast-moving low-level epifaunal carnivore
Distribution: found only at Coral Bed, Aux Sables River, Hungry Hollow, 2 miles east of Arkona (Devonian of Ontario)