“Stripetails, Springflies, Yellow Stones”
Genus Overview
The genus Isoperla contains over 57 species, making it one of the largest stonefly genera. Larvae prey on Chironomidae and Simuliidae (Diptera), Ephemeroptera, and Plecoptera; some feed as collectors-gatherers, especially when young. Members of this genus are mostly univoltine, meaning that they only have one generation per year. Emergence can occur throughout the spring and summer. To emerge, the larvae crawl out of the stream onto rocks or logs before molting to an adult. They are an important food source for trout in eastern streams. Fly fishermen often know them as the Light Stonefly, Light Brown Stonefly, or Little Yellow Stonefly, and often try to mimic the look of the larvae in their tied flies.
Characteristics
POLLUTION TOLERANCE
Southeast: 0 - 5.6
Upper Midwest: 2
Mid-Atlantic: 2
0 = least tolerant, 10 = most tolerant
FEEDING HABITS
Collector / Gatherer
Engulfer / Predator
Engulfer / Predator
MOVEMENT
Clinger
Sprawler
Sprawler
DISTRIBUTION
Widespread (east of the Rocky Mtns.)
HABITAT
Lotic-depositional
Lotic-erosional
Lotic-erosional
iNaturalist
Diagnostic Characters
