Pteronarcidae are very large, they are found in medium to large cool running rivers. Prefers swift rifles. Just like most stoneflies they are extremley sensitive to environmental stressors. They are found throughout North America and they are about 2 genera and approximatley 10 species.
Eggs are laid on top of water and hatch below the surface. They mature in 1 to 3 years and adults emerge in early summer. They are shredder/detritivore, consuming CPOM. Some species are faculative scrapers. Play an important role in many game fish diets.