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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.

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Mayfly Genus Stenacron (Light Cahill)

The species in this genus were formerly classified in Stenonema. See the genus Maccaffertium for details. Only one species, Stenacron interpunctatum, is important to fly fishermen. See its page for details.

Where & when

In 197 records from GBIF, adults of this genus have mostly been collected during May (27%), June (24%), April (19%), July (16%), and August (5%).

In 143 records from GBIF, this genus has been collected at elevations ranging from 3 to 9236 ft, with an average (median) of 2707 ft.

Genus Range

Specimens of the Mayfly Genus Stenacron

1 Male Dun
3 Female Duns
1 Male Spinner
1 Female Spinner
2 Nymphs

1 Streamside Picture of Stenacron Mayflies:

Discussions of Stenacron

8 replies
Posted by LittleJ on Nov 25, 2006
Last reply on Dec 1, 2006 by Troutnut
I know I'm a little out of season, butI was curious if you had any shots of Stenacron Interpunctatum next to your hook quide, or could just give me a size range. I was thinking they were 14-16 but could be wrong. Also you have written that Stenacron Interpunctatum were rarely called cahills. If so what mayfly is it that i'm after (that is common name "cahill"). The stenacron look the same to me, but i have also never kept and memorized any specimens.

Start a Discussion of Stenacron


Mayfly Genus Stenacron (Light Cahill)

Genus Range
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