Stonefly Species Sierracapnia yosemite (Little Snowflies)

Source: Sierracapnia, A New Genus Of Capniidae (Plecoptera) From Western North America

Male. Tergum 7 knob tall, thin, and narrowly divided at apex (knob height 30 - 35 % of segment 7 height; knob width 14 - 15 % of segment 7 width) (Figs. 34, 37). Epiproct in dorsal view with uniform width along length, maximum width 18 - 24 % of epiproct length; maximum width occurs anterior of mid epiproct; apex rounded or wedge-shaped, with a long thin posterior-projecting lobe (Fig. 35); dorsal membrane light colored. Epiproct in lateral view with a shallow reverse (S-shaped) curve dorsally and deep curve ventrally; maximum depth 25 - 30 % of length; maximum depth occurs in anterior third of epiproct; apex elongated and raised, with thin median lip that wraps around tip of eversible crest; neck narrow (Figs. 34, 36). Dorsolateral horns arch high above main epiproct body, exposing membrane of eversible crest in lateral view; horn length 18 - 21 % epiproct length; horn tips extend forward to 85 - 88 % of epiproct length (Fig. 36; Table 1).

Female. Subgenital plate heavily sclerotized and dark, plate covers entire width of sternum 8 from its posterior to anterior edge, sclerotization extends onto posterior third of sternum 7 (Fig. 257, Nelson and Baumann 1989).