stonefly, (order Plecoptera), any of about 2,000 species of insects, the adults of which have long antennae, weak, chewing mouthparts

What organism is a stonefly?

Stoneflies (Plecoptera) are a small order of hemimetabolous insects with about 3500 described extant species in 16 families and 286 genera (Fochetti and Tierno de Figueroa, 2008).

Is a stonefly a fly?

Stone flies are a diverse family of insects that are adapted to well oxygenated streams and rivers and cannot survive in polluted water. Stone fly nymphs have fixed gills that can only extract oxygen in clean moving water. If trapped in still stagnant water, they die quickly.