Tiny Baetis mayflies are perhaps the most commonly encountered and imitated by anglers on all American trout streams due to their great abundance, widespread distribution, and trout-friendly emergence habits.
Millcreek on Jan 11, 2015January 11th, 2015, 7:07 am EST
These are Ecdyonurus nymphs with Symbiocladius parasitizing them. They were collected from Mill Creek, a tributary of the Russian River. Symbiocladius are a member of Diptera, the true flies. They attach themselves behind the wingpads and grow to maturity there without harming the Ecdyonurus nymph. They parasitize Paraleptophebia and Rhithrogena as well though not in this area.
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