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 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.

Finally got an October Caddis

Finally got an October Caddis

By Troutnut on September 28th, 2017
I've been itching to photograph one of these for years and had an unexpected opportunity tonight when this one flew into a house full of aquatic scientists. It's the first insect I've collected for this site by chasing it around a kitchen with a tupperware container.

Closeup insects by Troutnut from the South Fork Snoqualmie River in Washington

Female Dicosmoecus gilvipes (Limnephilidae) (October Caddis) Caddisfly Adult from the South Fork Snoqualmie River in Washington
I've been hoping to add a really good October Caddis to the photo collection here for years, but so far I had struck out on finding them on the river. Tonight, this one flew into the kitchen during a pizza party at a house along the river, and was quickly pointed out -- one of the perks of hanging out with other aquatic biologists! Maybe next year I can finally get a salmonfly on taco night or something.

Comments / replies

Creno
Grants Pass, OR

Posts: 302
Creno on Sep 30, 2017September 30th, 2017, 1:23 pm EDT
Great Dicosmoecus pics Jason. I presume you kept it :-) The globular 9th I think I am seeing and the very dark, contrasting vein coloration are more typical of D. gilvipes. If you kept it take a good look at the spur count. D. atripes is 1-2-2 while D. gilvipes is 1-3-4. From what I can see the meso-tibia in several of the pics have 3 spurs. However, I am fairly sure fish don't count spurs :-) Have fun
creno
Troutnut
Troutnut's profile picture
Administrator
Bellevue, WA

Posts: 2758
Troutnut on Sep 30, 2017September 30th, 2017, 2:24 pm EDT
Thanks Dave. I was wondering about that, after looking up the paper with the spur counts after taking the pictures. I thought from the pictures it looked more like 1-2-2, but your comment prompted me to go back and check it under the dissecting microscope. It's 1-3-4, clear as day. I just don't have as good an eye for spurs versus those smaller spikes on the legs in the photos, but the difference was really obvious under the scope.
Jason Neuswanger, Ph.D.
Troutnut and salmonid ecologist
Wiflyfisher
Wiflyfisher's profile picture
Wisconsin

Posts: 622
Wiflyfisher on Oct 6, 2017October 6th, 2017, 2:47 am EDT
Jason, excellent!

Now that WI has an extended inland trout season I have been on the hunt for the elusive Great Autumn Brown Sedges (Pycnopsyche), especially the pupae. So far no success.

Quick Reply

Related Discussions

Topic
Replies
Last Reply
9
May 29, 2008
by Softhackle

References

Troutnut.com is copyright © 2004-2024 (email Jason). privacy policy