Sigmoria nigrimontis (Chamberlin 1947)

Sigmoria nigrimontis (Chamberlin)
Diagnosis. — A moderate-size species of Sigmoria with variable medial flange (often vestigial) on distal zone opposite lateral flange, and with red paranota and red metatergal stripes; gonopods highly variable but with following diagnostic characters: prefemoral process moderate to long, configuration variable; acropodite with regions poorly to well defined, arch extending to or beyond level of prefemoral process; basal zone widening in alternating perpendicular planes in some forms; peak flattened or gently curved; distal zone varying from short and terminating just below peak to long and extending to near level of prefemoral process; tip usually blunt, occasionally subacute, projecting dorsad from peak or bent sharply inward into arc; prostatic groove either running entirely along medial surface of acropodite or crossing to lateral side distal to anterior bend.

Sigmoria nigrimontis is a species of flat-backed millipede in the family Xystodesmidae. It is found in North America.