Order Plecoptera (Stoneflies)
Courtesy of the Cacapon InstituteLong thin antenna project in front of the head; wing pads usually present on the thorax but may only be visible in older larvae; three pairs of segmented legs attach to the thorax; two claws are located at the end of the segmented legs; gills occur on the thorax region, usually on the legs or bottom of the thorax, or there may be no visible gills (usually there are none or very few gills on the abdomen); gills are either single or branched filaments; two long thin tails project from the rear of the abdomen.  All stoneflies have low-very low (L) tolerance to many insults; however, several families are tolerant of slightly acidic conditions.  

Winter stoneflies


Capniidae (Small winter stonefly): Slender elongated body; front of thorax slightly wider than the abdomen; wing pads not divergent from the midline; abdominal segments separated by a membranous fold. Clinger/crawler; Shredder; S-M (F) [Adult]


Leuctridae (Rolled-wing stonefly): Slender elongated body; front of thorax slightly wider than the abdomen; wing pads not divergent from the midline; abdominal segments not separated by a membranous fold. Very similar characteristics to Capniidae. Clinger/crawler; Shredder; S-M (F) [Adult]


Taeniopterygidae (Winter stonefly): Stout bodies with pronotum much wider than the abdomen; wing pads greatly divergent from the midline. Clinger/crawler; Shredder/scraper; S-M (F) [Adult]

Patterned stoneflies


Chloroperlidae (Green stonefly): Body elongated, front of the thorax slightly wider than the abdomen; wing pads not divergent from the midline; tails shorter than the abdomen. Will sometimes have patterns similar to Perlodidae. Clinger/crawler; Shredder/predator; M (F) [Adult]


Perlidae (Common stonefly): Usually a large strikingly patterned and often having a golden color; finely branched gills present on all thoracic segments; wing pads diverge slightly from the midline. Clinger/crawler; Predator; M-L (F) [Adult]


Perlodidae (Perlodid stonefly): Strikingly patterned and colored similar in appearance to Perlidae; hind wing pads divergent; no gills on the thoracic segments. Clinger/crawler; Shredder; M-L (F) [Adult]

Other stoneflies


Nemouridae (Little brown stonefly): Very small, often hairy appearance; wing pads diverge greatly from the midline; hind legs as long as the abdomen; gills often present between the head and thorax. Clinger/crawler; Shredder; S-M (F/S) [Adult]


Peltoperlidae (Roach-like stonefly): Small stout body; rear divergent wing pads; thoracic segments are oval or triangular shaped and cover much of the upper body; some have fine gills on the front legs. Clinger/crawler; Shredder; S-M (F) [Adult]


Pteronarcyidae (Giant stonefly): Very large and usually dark brown in color; finely branched gills on all thoracic segments plus the first two abdominal segments. Clinger/crawler; Shredder; M-VL (F) [Adult]