← Gallery II · The Orders
No. 14 · Hemimetabolous
Stoneflies
Plecoptera
~3,700
Described species
~17
Families
Introduction
Stonefly nymphs are intolerant of pollution — their presence is a strong indicator of healthy stream ecosystems.
Field marks
Key ID traits.
Two pairs of membranous wings folded flat over abdomen at rest. Two long cerci. Aquatic nymphs require clean, cold, well-oxygenated streams — major bioindicators.
Etymology
Greek plekein 'to fold' + pteron 'wing'
Wings
Winged
Diet
Herbivore · Predator · Detritivore
Habitat
Aquatic · Semi-aquatic
Notable examples
Salmonfly, golden stonefly, little black stonefly.
Where to look