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**Mayfly Species Baetis flavistriga (BWO)**

Mayflies

Caddisflies

Stoneflies

Taxonomic Navigation -?-

Kingdom Animalia (Animals)

» Phylum Arthropoda (Arthropods)

» Class Insecta (Insects)

» Order Ephemeroptera (Mayflies)

» Family Baetidae (Blue-Winged Olives)

» Genus Baetis (Blue-Winged Olives)

» Species flavistriga (BWO)

Common Names

Match	Common Name
	BWO
	Dark Blue-Winged Olive
	Rusty Spinner
	Little Blue-Winged Olive
	Little Slate-Winged Brown Quill
	Dark Gray-Winged Olive Dun
	Dark Olive Brown Spinner

Pictures Below ↓

This is one of the most widespread and abundant Baetis species, and it may produce fishable hatches under a variety of conditions.

This species is known in angling books by several old synonyms (Synonym: A former name of a taxon, usually a species. Entomologists frequently discover that two insects originally described as different species are one in the same, and they drop one of the names. The dropped name is said to be a synonym of the remaining name. These changes take a while to trickle into the common knowledge of anglers; for example, Baetis vagans is now a synonym of Baetis tricaudatus.), including Baetis quebecensus, Baetis levitans, Baetis cingulatus, and Baetis phoebus, in addition to the correct name.

Where & When

Regions: East, Midwest, West

Time Of Year (?): May through August

The first flies of this species make their appearance a few weeks after Baetis tricaudatus. Because the species is a combination of widely varying types in different places, it's hard to piece the information together into reliable hatch dates for the different broods in any given location. The best hatches for which this species is credited occur in June.

Nymph Biology

Current Speed: Any; best in fast

Substrate: Gravel

Pictures of 3 Mayfly Specimens in the Species Baetis flavistriga:

Male Baetis flavistriga (BWO) Mayfly Nymph

View 8 PicturesThis nymph keys to Baetis assuming the villipore is present (hard to see in my photos or scope), and within that genus it tentatively keys to the flavistriga species complex, of which Baetis flavistriga itself is by far the most common in Washington state, so that's the most likely ID.

Collected July 6, 2020 from Mystery Creek #249 in Washington
Added to Troutnut.com by Troutnut on July 12, 2020

Baetis flavistriga (BWO) Mayfly Nymph

View 1 Pictures

Collected June 19, 2011 from the Kwethluk River in Alaska
Added to Troutnut.com by Bnewell on June 26, 2011

Baetis flavistriga (BWO) Mayfly Nymph

View 5 PicturesThis specimen keys to the Baetis flavistriga complex, which could be either flavistriga or Baetis phoebus.

Collected August 3, 2020 from the East Fork Big Lost River in Idaho
Added to Troutnut.com by Troutnut on August 19, 2020

Recent Discussions of Baetis flavistriga

Baetis flavistriga computatii 7 Replies »

Posted by CaseyP on Jan 22, 2007

Last reply on Jan 19, 2009 by Taxon

pleased to report the emergence of a new baetis flavistriga which i have christened computatii

forum visitors using the Firefox browser who put troutnut.com on their bookmarks toolbar have undoubtedly noticed a tiny dark mayfly icon in a blue box next the bookmark.

well, it's breeding. came back this evening from a week out of town to discover that the little troutnut computatii had a pal over next the hotmail.com bookmark where formerly there was only a generic white icon. am waiting for it to show up next the other two sites that have only generic icons.

now our resident boffins will help me with the Latin ending on the new name, (i tried to use the genitive plural) and then we'll ask Jason how he got these virtual flies to multiply.

Casey

Reply flavistriga broods

Posted by Konchu on Jan 18, 2009

Anyone have observations that they are willing to share of different flavistriga broods?

Jason says that B. flavistriga is a "combination of widely varying types in different places, it's hard to piece the information together into reliable hatch dates for the different broods in any given location." This is stated very well.

As part of my bug work, I'm trying to tease apart some of these "varying types" to see what, if anything, they might represent. Tapping into the experience base here might help.

Your Thoughts On Baetis flavistriga:

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Jargon Defined:

Broods: When a species produces more than one generation per year, each one is called a brood.

Nymph: The juvenile, underwater stages of mayflies, stoneflies, dragonflies, and damselflies and other aquatic insects whose juvenile stages are covered by hard exoskeletons. The word can also refer to the fishing flies which imitate these creatures, in which case it is used as a blanket term for flies imitating any underwater stage of an invertebrate (except for crayfish and leeches).

Synonyms: A former name of a taxon, usually a species. Entomologists frequently discover that two insects originally described as different species are one in the same, and they drop one of the names. The dropped name is said to be a synonym of the remaining name. These changes take a while to trickle into the common knowledge of anglers; for example, Baetis vagans is now a synonym of Baetis tricaudatus.

Useful References:

Arbona, Fred Jr. 1989. Mayflies, the Angler, and the Trout. Nick Lyons Books.

Caucci, Al and Nastasi, Bob. 2004. Hatches II. The Lyons Press.

Knopp, Malcolm and Robert Cormier. 1997. Mayflies: An Angler's Study of Trout Water Ephemeroptera . The Lyons Press.

Leonard, Justin W. and Fannie A. Leonard. 1962. Mayflies of Michigan Trout Streams. Cranbrook Institute of Science.

Swisher, Doug and Carl Richards. 2000. Selective Trout. The Lyons Press.