The dark, hairless, sclerotized rectangle on the subgenital plate (in focus in this picture) is a key identifying characteristic for Hesperoperla pacifica.
Female Hesperoperla pacifica (Golden Stone) Stonefly Adult from the Henry's Fork of the Snake River in Idaho
Troutnut.com is a collection of pictures and information about fly fishing. Fly fishermen, fly tiers, and trout enthusiasts of all stripes can learn more about life beneath the surface of trout streams, as well as how to better imitate aquatic insects with artificial flies to catch trout. There are aquatic insect pictures, underwater pictures, landscape pictures, and a comprehensive reference to the common names of trout stream insects.
