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.

Stream photos

Featured on the forum

Re: Trico emergers
In the Mayfly Genus Tricorythodes by Bwoklink (Martinlf replied)

Re: Trico Tips
In the Mayfly Genus Tricorythodes by Martinlf

Re: UV spectrum and trout
In General Discussion by Martinlf

Re: closing the gender gap in flyfishing
In General Discussion by Konchu (Smallflyguy replied)

Re: Fishing Kupa River, Slovenia
In Fishing Reports by Slocum (Fish1 replied)

Holocentropus Caddisfly Larva Holocentropus Caddisfly Larva

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.

11 Recently Added Photos

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.

Male Afghanurus inconspicua Mayfly Dun Pictures

This pretty little dun was part of a sparse midsummer evening hatch on a large Catskill river.

I could not identify it by following a species key step by step, but I tentatively keyed it to the genus Nixe, and based on distribution maps and physical descriptions the most likely species is Nixe inconspicua. (Edit in 2023: this species was recently moved from Nixe into Afghanurus.)

Male Afghanurus inconspicua (Heptageniidae) Mayfly Dun from the East Branch of the Delaware River in New York

Ventral view of a Male Afghanurus inconspicua (Heptageniidae) Mayfly Dun from the East Branch of the Delaware River in New York

Ruler view of a Male Afghanurus inconspicua (Heptageniidae) Mayfly Dun from the East Branch of the Delaware River in New York The smallest ruler marks are 1/16".

Dorsal view of a Male Afghanurus inconspicua (Heptageniidae) Mayfly Dun from the East Branch of the Delaware River in New York

Lateral view of a Male Afghanurus inconspicua (Heptageniidae) Mayfly Dun from the East Branch of the Delaware River in New York

The ratio of segment lengths on the tarsus of this dun is a helpful identifying characteristics.

Male Afghanurus inconspicua (Heptageniidae) Mayfly Dun from the East Branch of the Delaware River in New York

Artistic view of a Male Afghanurus inconspicua (Heptageniidae) Mayfly Dun from the East Branch of the Delaware River in New York

This mayfly was collected from the East Branch of the Delaware River in New York on July 13th, 2005 and added to Troutnut.com by Troutnut on April 14th, 2006.

Discussions of this Dun

Maybe Epeorus

16 replies

Posted by Troutnut on Jul 5, 2006

Last reply on Sep 22, 2011 by Oldredbarn

I'll have to revisit the identification on this one. Originally the fore tarsal ratio made me think it's not Epeorus, but the unmarked wings, costal wing venation, and contiguous eyes now make me think otherwise.

Start a Discussion of Dun