|1a. Genital hooks long and developed from hind margin of the tenth tergum; anterior to base of cerci.|
|1b. Genital hooks shorter and triangular in shape; developed from paraprocts, posterior to cercal bases.|
|2a. Tenth tergum with mesal tergite separated anteriorly and laterally by membranous areas. Hammer almost square.|
|2b. Tenth tergum without separated tergite, but sometimes with light sclerotization. Hammer oval|
ReferencesKeys and illustrations modified from the following:
Stark,BP; Gaufin,AR 1976 The nearctic genera of Perlidae (Plecoptera). Miscellaneous Publications of the Entomological Society of America 10, 1-80.
Baumann,RW; Gaufin,AR; Surdick,RF 1977 The stoneflies (Plecoptera) of the Rocky Mountains. Memoirs of the American Entomological Society 31, 1-208.
Good LinksKey to Perlidae Females
Key to Perlidae Nymphs