Oemopteryx contorta

Oemopteryx contorta (Needham & Claassen, 1925) Notes This species is commonly referred to as the Dark Willowfly (Stark et al. 2012). Oemopteryx contorta is distributed along the Appalachian Mountains from Maine southwest to North Carolina and Tennessee (Stewart 2000, DeWalt et al. 2024, Verdone et al. 2025). Nelson (1982) studied the life history of this species in Tennessee and found that larvae exhibited a univoltine-slow life cycle. Larvae were first collected in October, and adult emergence occurred in April. In New York, this species is uncommon and apparently restricted to smaller streams with records available from Level IV Ecoregions Glaciated Reading Prong / Hudson Highlands (58 i), Taconic Foothills (58 x), Adirondack High Peaks (58 z), Central Adirondacks (58 ad), and Catskills Transition (60 c) (Fig. 21 f). Adults have been collected from early March through late April (Fig. 22) from small, cold streams at elevations ranging from 234-480 m asl (Fig. 23).