Header image
Enter a name
Artistic view of a Male Pteronarcys californica (Pteronarcyidae) (Giant Salmonfly) Stonefly Adult from the Gallatin River in Montana
Salmonflies
Pteronarcys californica

The giant Salmonflies of the Western mountains are legendary for their proclivity to elicit consistent dry-fly action and ferocious strikes.

Dorsal view of a Ephemerella mucronata (Ephemerellidae) Mayfly Nymph from the Yakima River in Washington
This is an interesting one. Following the keys in Merritt R.W., Cummins, K.W., and Berg, M.B. (2019) and Jacobus et al. (2014), it keys clearly to Ephemerella. Jacobus et al provide a key to species, but some of the characteristics are tricky to interpret without illustrations. If I didn't make any mistakes, this one keys to Ephemerella mucronata, which has not previously been reported any closer to here than Montana and Alberta. The main character seems to fit well: "Abdominal terga with prominent, paired, subparallel, spiculate ridges." Several illustrations or descriptions of this holarctic species from the US and Europe seem to match, including the body length, tarsal claws and denticles, labial palp, and gill shapes. These sources include including Richard Allen's original description of this species in North America under the now-defunct name E. moffatae in Allen RK (1977) and the figures in this description of the species in Italy.
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.

Ephemerella subvaria (Hendrickson) Mayfly Nymph Pictures

I've never seen this strange coloration on any Ephemerella subvaria nymph in a book before, but it's similar to several other specimens I collected on the same outing, including a smaller one that I photographed. They were outnumbered by the "normal" Ephemerella subvaria nymphs in the sample.

Ventral view of a Ephemerella subvaria (Ephemerellidae) (Hendrickson) Mayfly Nymph from Salmon Creek in New York
Dorsal view of a Ephemerella subvaria (Ephemerellidae) (Hendrickson) Mayfly Nymph from Salmon Creek in New York
Ephemerella subvaria (Ephemerellidae) (Hendrickson) Mayfly Nymph from Salmon Creek in New York
Ephemerella subvaria (Ephemerellidae) (Hendrickson) Mayfly Nymph from Salmon Creek in New York

This mayfly was collected from Salmon Creek in New York on March 29th, 2006 and added to Troutnut.com by Troutnut on April 7th, 2006.

Discussions of this Nymph

Has anyone else seen a Hendrickson nymph like this?
14 replies
Posted by Troutnut on Oct 31, 2006
Last reply on Mar 19, 2010 by Backcast
I found a few of these this spring in just one small Finger Lakes tributary, mixed in with various normal-looking E. subvaria nymphs. The unusual characteristic is the pale prothorax -- the "white collar" segment just behind the head. I've never heard of that color configuration before. Has anyone else?

Maybe they're mayfly clergy...
Hendrickson nymph
3 replies
Posted by Martinlf on Dec 23, 2006
Last reply on Dec 27, 2006 by GONZO
This photo shows the light band on the top of the subvaria nymph. The lighter collar seems to be abnormal, or at least an unusual color variation, if I remember the previous discussion on this photo.

I just noted the photo of the bug's belly. It appears solid brown, much to my surprise. Hmm. . . Gonzo? I believe he's away for the holidays, but I'll be interested in his answer on imitating this and other nymphs.

I've navigated away from the photo of the subvaria's underwater on the rock, but they are awesome too.

Start a Discussion of Nymph

References

Ephemerella subvaria (Hendrickson) Mayfly Nymph Pictures

Collection details
Location: Salmon Creek, New York
Date: March 29th, 2006
Added to site: April 7th, 2006
Author: Troutnut
Troutnut.com is copyright © 2004-2024 (email Jason). privacy policy