Ephedrus clavicornis sp n. (Hymenoptera, Braconidae, Aphidiinae), an aphidparasitoid of the Pacific Northwest, and key to Nearctic Ephedrus

A new aphid parasitoid species, Ephedrus clavicornis (Hymenoptera, Braconid ae. Aphidiinae) is described. Known from Washington and British Columbia, i t was found most frequently in association with aphids [Aphis (Bursaphis) n r. oenotherae, and A. varians Patch] on fireweed and willow-herb [Epilobium spp.] in open forest and mountain habitats. It was found infrequently on o ther hosts, viz. Aphthargelia symphoricarpi (Thomas) on Symphoricarpos sp.; Dysaphis plantaginea (Passerini) on Pyyrus malus; Illinoia maxima (Mason) on Rubus parviforus; Prociphilus sp. on Amelanchier alnifolia; and Sitobion avenae (Fabricius) on Agropyron caninum. A key to the Nearctic Ephedrus sp p. is provided.