Silver Striped Sedge?

Kilchis

WFF Supporter
Yesterday, March 5, I fished A little 3-acre lakelet at 2400 feet on the southwest extension of Mt Hebo in northern Oregon's Coast Range, about 20 miles north of the 45th parallel. The air temperature was 48f at 1:30 in the afternoon, declining to 42f by 3:30. The lake was enveloped in fog all of the windless afternoon. The water temperature 4” below the surface was 39f. Given the cold and clammy conditions I was amazed when this large insect clambered into view from around a curve on my float tube while I was mid-lake. I expect to see size 40 gnats this time of year, not anything this large. From wingtip to antenna tip the bug's overall length was just about 2 1/8 inches.

Through the magic of Google I have tentatively identified this as a Hesperophylax Designatus, commonly known as the Silver Striped Sedge. I welcome confirmation or correction. For reference, the Velcro tab at upper right is 7/8 of an inch wide, not including the material visible under the top component.

Fishing was great! Catching much less so.

D8D52A4D-EA12-4B1D-9793-188CF76230FC.jpeg
 

jamma

Active Member
My only concern for that ident is, according to LaFontaine's book 'Caddisflies', the Hesperophylax is a running water insect found in the east and Midwest so that's probably doubtful. Let me do so extra research and I'll get back to you.
 

jamma

Active Member
My only concern for that ident is, according to LaFontaine's book 'Caddisflies', the Hesperophylax is a running water insect found in the east and Midwest so that's probably doubtful. Let me do so extra research and I'll get back to you.
It appears that what we have here is the genus Limnephilus sericeus, also known as the Cinnamon sedge, common on stillwaters across the nation but definitely out of season as they are also known as the Summer Flier sedge or late summer sedge. We did have a mild dry winter so it is not entirely out of the question to see one of these at this time of year.

Go on Google and type in large cinnamon western stillwater caddisfly and you will get a link to Dave Hughes' western hatches guide page on this critter. ;)
 
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Kilchis

WFF Supporter
That may well be. I did, however, find several references to the designatus ranging from Alaska to California in the west. In my initial identification attempt I also found, and lost, a reference map that showed the critter being found in a few dozen locations in Oregon. The lake I fished is fed by a very small stream.

It doesn't much matter to me, I just thought it was a remarkable insect to see given the time of year.
 

jamma

Active Member
That may well be. I did, however, find several references to the designatus ranging from Alaska to California in the west. In my initial identification attempt I also found, and lost, a reference map that showed the critter being found in a few dozen locations in Oregon. The lake I fished is fed by a very small stream.

It doesn't much matter to me, I just thought it was a remarkable insect to see given the time of year.
It is an old reference book and in places acknowledges it's incompleteness, but at the time, it was the only book submitted for peer review by a certified entomologist. Just for my benefit, what sources did you consult? Outside of scientific studies, an updated book for the layman would be appreciated. In his forward to the Cormier/Knopp book on mayflies, Gary illustrates how difficult this process can be to humorous effect.
Fun fact, in Gary's book the two species are profiled one after the other.
A common problem in these threads are field photographs don't always show enough detail for positive identification.

P.S. I gave everyone a shot at this yet no one responded so, under the bylaws of the Washington Fly Fishing website, I gotta say:

Atlantic salmon. :D
 
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Taxon

WFF Moderator
Hi Kilchis-

Rather than this caddisfly being a Silver Stripe Sedge (genus Hesperophylax), I believe it to actually be a Snow Sedge (genus Pycnoglypha), both of which have a silver stripe running down the center of their wing. Although both genera are present in Oregon, only a Snow Sedge would be present in its adult lifestage in the month of March. For comparison purposes, please see https://bugguide.net/node/view/1643714.
 

Matt B

...
WFF Supporter
Yesterday, March 5, I fished A little 3-acre lakelet at 2400 feet on the southwest extension of Mt Hebo in northern Oregon's Coast Range, about 20 miles north of the 45th parallel. The air temperature was 48f at 1:30 in the afternoon, declining to 42f by 3:30. The lake was enveloped in fog all of the windless afternoon. The water temperature 4” below the surface was 39f. Given the cold and clammy conditions I was amazed when this large insect clambered into view from around a curve on my float tube while I was mid-lake. I expect to see size 40 gnats this time of year, not anything this large. From wingtip to antenna tip the bug's overall length was just about 2 1/8 inches.

Through the magic of Google I have tentatively identified this as a Hesperophylax Designatus, commonly known as the Silver Striped Sedge. I welcome confirmation or correction. For reference, the Velcro tab at upper right is 7/8 of an inch wide, not including the material visible under the top component.

Fishing was great! Catching much less so.

View attachment 228990
Check this out- I had a very similar experience as you with the early March encounter and thinking it to be a silver striped sedge. March 3 2016:

Snow sedge does make more sense.
 

garyk

Active Member
FWIW, this caddisfly is commonly found on the Metolius River in late winter. It makes a good subject for macro photography. I had thought it was Hesperophylax.
 

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