| 1a. Cervical gills present. | |
| 1b. Cervical gills absent. | |
| 2a. Cervical gills highly branched. | |
| 2b. Cervical gills simple, never more than four branches. Nemourinae (in part) Zapada |
|
| 3a. Some cervical gills branch midway out their length; Eight sternum sclerotized along median notch only.
(Gills have a Y-shape) |
|
| 3b. Cervical gills branch from base at the neck; Eighth sternum with sclerotized vaginal lobes. | |
| 4a. Eighth sternum with distinct sclerotized median stripe. | |
| 4b. Eight sternum without distinct sclerotized pattern. |
LinksKey to Nemouridae NymphsKey to Nemouridae Males ReferencesKeys and illustrations from the following publications were altered to construct this key:Baumann,RW; Gaufin,AR; Surdick,RF 1977 The stoneflies (Plecoptera) of the Rocky Mountains. Memoirs of the American Entomological Society 31, 1-208. Stewart,KW; Harper,PP 1996: Plecoptera. In: An Introduction to the Aquatic Insects of North America. 3rd ed. Eds: Merritt,RW; Cummins,KW Kendall/Hunt Publishing Company, Dubuque, Iowa, 217-266. Ward,JV; Kondratieff,BC; Zuellig,RE 2002: An Illustrated Guide to the Mountain Stream Insects of Colorado. 2nd ed. University Press of Colorado, Boulder, Colorado. 219 pages. Updated 2May2004 |