Header image
Enter a name
Lateral view of a Female Hexagenia limbata (Ephemeridae) (Hex) Mayfly Dun from the Namekagon River in Wisconsin
Hex Mayflies
Hexagenia limbata

The famous nocturnal Hex hatch of the Midwest (and a few other lucky locations) stirs to the surface mythically large brown trout that only touch streamers for the rest of the year.

Dorsal view of a Holocentropus (Polycentropodidae) Caddisfly Larva from the Yakima River in Washington
This one seems to tentatively key to Holocentropus, although I can't make out the anal spines in Couplet 7 of the Key to Genera of Polycentropodidae Larvae nor the dark bands in Couplet 4 of the Key to Genera of Polycentropodidae Larvae, making me wonder if I went wrong somewhere in keying it out. I don't see where that could have happened, though. It might also be that it's a very immature larva and doesn't possess all the identifying characteristics in the key yet. If Holocentropus is correct, then Holocentropus flavus and Holocentropus interruptus are the two likely possibilities based on range, but I was not able to find a description of their larvae.
27" brown trout, my largest ever. It was the sub-dominant fish in its pool. After this, I hooked the bigger one, but I couldn't land it.
Troutnut is a project started in 2003 by salmonid ecologist Jason "Troutnut" Neuswanger to help anglers and fly tyers unabashedly embrace the entomological side of the sport. Learn more about Troutnut or support the project for an enhanced experience here.

Rhithrogena hageni (Western Black Quill) Mayfly Nymph Pictures

I'm basing the ID of this near-mature nymph on a male spinner with similar size and markings, collected on the same trip. There isn't a key to reliably identify the nymphs of most Rhithrogena species otherwise.

Dorsal view of a Rhithrogena hageni (Heptageniidae) (Western Black Quill) Mayfly Nymph from Mystery Creek #249 in Washington
Rhithrogena hageni (Heptageniidae) (Western Black Quill) Mayfly Nymph from Mystery Creek #249 in Washington
Rhithrogena hageni (Heptageniidae) (Western Black Quill) Mayfly Nymph from Mystery Creek #249 in Washington
Ventral view of a Rhithrogena hageni (Heptageniidae) (Western Black Quill) Mayfly Nymph from Mystery Creek #249 in Washington
Rhithrogena hageni (Heptageniidae) (Western Black Quill) Mayfly Nymph from Mystery Creek #249 in Washington
Body 11 mm long

Ruler view of a Rhithrogena hageni (Heptageniidae) (Western Black Quill) Mayfly Nymph from Mystery Creek #249 in Washington The smallest ruler marks are 1 mm.
Rhithrogena hageni (Heptageniidae) (Western Black Quill) Mayfly Nymph from Mystery Creek #249 in Washington
Rhithrogena hageni (Heptageniidae) (Western Black Quill) Mayfly Nymph from Mystery Creek #249 in Washington
Rhithrogena hageni (Heptageniidae) (Western Black Quill) Mayfly Nymph from Mystery Creek #249 in Washington

This mayfly was collected from Mystery Creek #249 in Washington on July 4th, 2020 and added to Troutnut.com by Troutnut on July 12th, 2020.


Start a Discussion of Nymph

Rhithrogena hageni (Western Black Quill) Mayfly Nymph Pictures

Collection details
Location: Mystery Creek #249, Washington
Date: July 4th, 2020
Added to site: July 12th, 2020
Author: Troutnut
Troutnut.com is copyright © 2004-2024 (email Jason). privacy policy