The "Hendrickson" (ephemerella subvaria) is one of the very first mayflies to hatch here in the Northeast. Certainly not an ephemera of freestone rivers and streams. The nymphs much prefer the mud and detritus of slower moving streams and the bottoms of ponds.
I have tied the imitations both with spun chestnut dyed rabbit fur and a gray dun wing, that or a grey dyed CDC wing.
Also known as the "Red Quill" tied in the "Catskill" style with a stripped red quill body and a dun colored hackle wing tied in that classic style.
The nymphal stage is best imitated with a spun chestnut dyed rabbit fur body (much like the gold-ribbed hare's ear but more slender) with splayed brown hackle points for the tails and a thorax of gray mallard wing case.
Oops...here I go with my other obsession...
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