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

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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.

Stenonema ithaca (Light Cahill) Mayfly Nymph Pictures

This specimen seems to be of the same species as a dun I photographed which emerged from another nymph in the same sample.

Ruler view of a Stenonema ithaca (Heptageniidae) (Light Cahill) Mayfly Nymph from Paradise Creek in Pennsylvania The smallest ruler marks are 1 mm.

Dorsal view of a Stenonema ithaca (Heptageniidae) (Light Cahill) Mayfly Nymph from Paradise Creek in Pennsylvania

Ventral view of a Stenonema ithaca (Heptageniidae) (Light Cahill) Mayfly Nymph from Paradise Creek in Pennsylvania

Stenonema ithaca (Heptageniidae) (Light Cahill) Mayfly Nymph from Paradise Creek in Pennsylvania

Lateral view of a Stenonema ithaca (Heptageniidae) (Light Cahill) Mayfly Nymph from Paradise Creek in Pennsylvania

This mayfly was collected from Paradise Creek in Pennsylvania on May 29th, 2007 and added to Troutnut.com by Troutnut on June 4th, 2007.

Discussions of this Nymph

Maccaffertium mediopunctatum

1 replies

Posted by Taxon on Jun 5, 2007

Last reply on Jun 5, 2007 by Quillgordon

Maccaffertium is a Latinized version of the name of the world-renowned mayfly systematist, W. Patrick McCafferty. And, mediopunctatum is constructed from roots of medi- meaning middle, and punct- meaning point, so I assume this species has some distinctive feature midpoint in its anatomy. Assuming my logic is valid, perhaps someone else can tell you what the feature is.

The distribution of this species is confined to the states and provinces lying east of the N. American continental divide.

Name basis.....

Posted by Quillgordon on Jun 5, 2007

Last reply on Jun 5, 2007 by Quillgordon

This is the same specimen that I collected from a stream nearby.
Can anyone tell me the history( name basis) for this insect ?
Is it common across the country?

Thanks....

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