perlid sp.

This is a large stonefly in the family Perlidae. The adult does not feed and the nymph is an aquatic predator of insects and other invertebrates. Perlidae is the largest known family of stoneflies with more than 1,000 known species. Adults vary in size but can be as long as 40 mm and can be found worldwide except for parts of Africa and Australia. 

Order: Plecoptera
Family: Perlidae

Photograph: © 2007 RKD Peterson
Date of Photograph: 16 June 2007
Location: Montana, Gallatin Co. (45o27'17" N 111o14'24" W)