|Introduction |Identification Key |

Order Plecoptera

(Stoneflies)

All stoneflies inhabit freshwater as nymphs. The majority of the 500 North American species are restricted to cool, highly oxygenated waters and thus are good indicators of water quality. Stoneflies undergo incomplete metamorphosis, and nymphs may pass through as many as 22 larval instars before emerging as adults. Many species are adapted for emergence during winter months.
Examples of common stoneflies: