Brushleg Mayfly vs Dark Hendrickson Mayfly

Side-by-side species comparison

Attribute Brushleg Mayfly Dark Hendrickson Mayfly
Scientific Name Isonychia bicolor Leptophlebia cupida
Order Ephemeroptera Ephemeroptera
Family Isonychiidae Leptophlebiidae
Size 12-18 mm 8-12 mm
Habitat Rivers & Streams Rivers & Streams
Diet Omnivores Detritivores
Regions North America North America
Conservation Least Concern Least Concern

Brushleg Mayfly

A large, fast-swimming mayfly with forelegs fringed with bristles for filter feeding. Nymphs inhabit swift riffles of large streams and rivers.

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Did You Know?

Unlike most mayflies, nymphs crawl out of water onto rocks to emerge as adults rather than hatching at the surface.

Dark Hendrickson Mayfly

A dark-bodied spring mayfly important to trout anglers in the Northeast. Nymphs inhabit leaf packs and debris in slow to moderate stream sections.

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Did You Know?

It often emerges alongside Ephemerella subvaria, and the two species together form the famed Hendrickson hatch.