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**Mayfly Species Callibaetis ferrugineus (Speckled Spinner)**

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Taxonomic Navigation -?-

Kingdom Animalia (Animals)

» Phylum Arthropoda (Arthropods)

» Class Insecta (Insects)

» Order Ephemeroptera (Mayflies)

» Family Baetidae (Blue-Winged Olives)

» Genus Callibaetis (Speckled Spinners)

» Species ferrugineus (Speckled Spinner)

Common Names

Match	Common Name
	Speckled Spinner
	Speckled Dun
	Grizzly Quill
	Speckled-Winged Spinner

Pictures Below ↓

The sub-species Callibaetis ferrugineus ferrugineus and Callibaetis ferrugineus hageni taken together are by far the most important Callibaetis taxon in American trout waters. In extant angling literature, the sub-species ferrugineus ferrugineus inhabiting the east and Midwest is referred to as ferrugineus sans the sub-species name. In the West, Callibaetis ferrugineus hageni is referred to by many old and familiar 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.), such as americanus, nigritus, and coloradensis. While important in the East and Midwest, it is in the West where Callibaetis ferrugineus hageni has achieved legendary status. Many western stillwater anglers look to the hatches of these speckled duns and spinners as the highlight of their seasons and have coined the phrase "gulpers" to describe the trout's feeding activity. In the West, some spring fed lower elevation lakes with longer growing seasons can produce as many as three discrete broods. In typical baetid fashion, these broods will be larger and darker in the Spring tending smaller and lighter as the season progresses.

Where & When

Regions: East, Midwest, West

Time Of Year (?): Early May through September

Preferred Waters: Stillwater

Altitude: Variable

Because this taxon is the combination of what were once thought to be a variety of different species, previously published hatch charts are unreliable unless they are related to a particular region. Different books dealing with one synonym (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.) or another give a variety of different dates, colors, and sizes, basically showing that this species may be found through most of the season and in a variety of configurations. It usually produces two broods but can produce three in regions of the West with a longer growing season, and the angler should consult local hatch charts for their peak times and other relevant information.

Hatching Behavior

Time Of Day (?): Periods of calm, usually mid morning

Habitat: Littoral zones of lakes and ponds or very slow weedy margins of rivers and streams

See Hatching Behavior on the Callibaetis genus hatch page for pertinent information.

Spinner Behavior

Time Of Day: Mid-morning or mid-evening

See Spinner Behavior on the Callibaetis genus hatch page for pertinent information.

Nymph Biology

Current Speed: Slow

Substrate: Vegetation, silt

Environmental Tolerance: Does well in cold water

See Nymph Biology on the Callibaetis genus hatch page for pertinent information.

Pictures of 4 Mayfly Specimens in the Species Callibaetis ferrugineus:

Specimen Page:12

Female Callibaetis ferrugineus (Speckled Spinner) Mayfly Dun

View 3 Pictures

Collected July 14, 2004 from unknown in Wisconsin
Added to Troutnut.com by Troutnut on January 25, 2006

Callibaetis ferrugineus (Speckled Spinner) Mayfly Adult

View 3 PicturesThese adults are probably C. ferrugineus.

Collected August 13, 2009 from the Flathead River-lower in Montana
Added to Troutnut.com by Bnewell on June 27, 2011

Female Callibaetis ferrugineus (Speckled Spinner) Mayfly Spinner

View 9 Pictures

Collected September 4, 2020 from Silver Creek in Idaho
Added to Troutnut.com by Troutnut on September 18, 2020

Specimen Page:12

Recent Discussions of Callibaetis ferrugineus

Callibaetis Spinner Habits 8 Replies »

Posted by WildcatRob on Sep 8, 2007

Last reply on Jan 7, 2009 by Dgracia

With almost 40 years lake fishing experience in the Northwest (Washington) our callibaetis always seem to start hatching mid afternoon in the evening, mate overnight then the spinners start in the morning. The spinners draw the most intense "rise." I put rise in quotes because it is so delicate there it leaves almost no disturbance at all not even a sip.

Any comments? Hopefully contradictions?

Rob

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Jargon Defined:

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

Duns: Mayflies have two adult stages. They first emerge from the water as duns (scientifically known as the subimago stage). They then molt into the spinner (imago) stage, in which they mate and die. Sometimes the word "dun" is confusingly used to refer to a brownish gray color in fly tying materials.

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).

Spinner: There are two winged stages of adult mayflies. They emerge from the water as duns, molt on land (usually) into their fully mature stage, spinners. As spinners, they mate, lay eggs, and die.

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:

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

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

Schwiebert, Ernest G. 1955. Matching the Hatch. MacMillan Publishing Company.

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