Insecta - Orthoptera - Geraridae

Synonym: Gerarus longicollis Handlirsch 1911

Full reference: A. Handlirsch. 1911. New Paleozoic Insects from the Vicinity of Mazon Creek, Illinois. American Journal of Science 31:297-326

Belongs to Gerarus according to L. Burnham 1983

Sister taxa: Gerarus bruesi, Gerarus constrictus, Gerarus fischeri, Gerarus mazonus, Gerarus teutonicus, Gerarus vetus

Type specimens:

• Gerarus collaris: YPM 34, an exoskeleton. Its type locality is Mazon Creek (YPM collection), which is in a Westphalian D deltaic mudstone in the Carbondale Formation of Illinois.
• Gerarus longicollis: YPM 36, an exoskeleton. Its type locality is Mazon Creek (YPM collection), which is in a Westphalian D deltaic mudstone in the Carbondale Formation of Illinois.

Ecology:

Average measurements (in mm): forewing length 43.3