Lateral view of a Male Baetis (Baetidae) (Blue-Winged Olive) Mayfly Dun from Mystery Creek #43 in New York

Blue-winged Olives
Baetis

Tiny Baetis mayflies are perhaps the most commonly encountered and imitated by anglers on all American trout streams due to their great abundance, widespread distribution, and trout-friendly emergence habits.

Stream photos

Featured on the forum

Re: Trico emergers
In the Mayfly Genus Tricorythodes by Bwoklink (Martinlf replied)

Re: Trico Tips
In the Mayfly Genus Tricorythodes by Martinlf

Re: UV spectrum and trout
In General Discussion by Martinlf

Re: closing the gender gap in flyfishing
In General Discussion by Konchu (Smallflyguy replied)

Re: Fishing Kupa River, Slovenia
In Fishing Reports by Slocum (Fish1 replied)

Limnephilus (Summer Flier Sedge) Caddisfly Larva Limnephilus (Summer Flier Sedge) Caddisfly Larva

Case view of a Limnephilus (Limnephilidae) (Summer Flier Sedge) Caddisfly Larva from the Yakima River in Washington

24 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.

Where To Find Trico Nymphs

This topic is about the Mayfly Genus Tricorythodes

A cult following is something to which few insects can lay claim, but the tiny Tricorythodes mayflies certainly qualify. Their widespread, reliable, heavy hatches draw impressive rises of ultra-selective trout which demand the most of a technical dry-fly angler's skills.

It is surprising that such a great hatch took so long to come to the attention of fly fishermen. The Tricos were first introduced to anglers in a 1969 Outdoor Life article by Vincent Marinaro, who misidentified them as Caenis. By the early 1970s the identification had been corrected but Swisher and Richards still wrote in Selective Trout, "Few anglers are familiar with these extremely small but important mayflies." The next wave of publications boosted Tricorythodes to its current fame. I suspect their early dismissal was due in part to tackle limitations; anglers in the 1950s had no means to effectively tie and present size 22-28 flies.

Example specimens

5
Female Tricorythodes (Trico) Mayfly Spinner

Lateral view of a Female Tricorythodes (Leptohyphidae) (Trico) Mayfly Spinner from the Bitterroot River in Montana

This female Trico was collected with an associated male and many others.

6
Male Tricorythodes (Trico) Mayfly Spinner

Lateral view of a Male Tricorythodes (Leptohyphidae) (Trico) Mayfly Spinner from the Bitterroot River in Montana

This specimen was collected along with a female. The forewing venation and styliger plate of the male give a confident identification as Tricorythodes explicatus according to Baumgardner 2009.

9
Tricorythodes (Trico) Mayfly Nymph

Dorsal view of a Tricorythodes (Leptohyphidae) (Trico) Mayfly Nymph from Mystery Creek #308 in Washington

Lastchance
Portage, PA

Posts: 437

Lastchance on Jul 2, 2011July 2nd, 2011, 2:40 pm EDT

Do they attach themselves in the silt near the shore? I'd like to study a few of them.
Thanks,
Bruce

Konchu

Site Editor
Indiana

Posts: 498

Konchu on Jul 2, 2011July 2nd, 2011, 4:25 pm EDT

I have found them among rocks where there's some flow in the stream, but theres often a fair amount of silt in with them. Doesn't mean they're not where you suggested--just my experience.

Spinnerfall

Boulder, CO

Posts: 3

Spinnerfall on Jul 9, 2011July 9th, 2011, 9:38 pm EDT

Informative. Thanks Konchu!

Entoman

Northern CA & ID

Posts: 2604

Entoman on Jul 10, 2011July 10th, 2011, 9:41 am EDT

Hi Tim,

I've also found them at the bases of rooted weeds in the silt, and in the weeds themselves as they stage for hatching.

Regards,

Kurt

"It's not that I find fishing so important, it's just that I find all other endeavors of Man equally unimportant... And not nearly as much fun!" Robert Traver, Anatomy of a Fisherman