Troutnut.com Fly Fishing for Trout Home
User Password
or register.
Scientific name search:

Great Red Spinners

Like most common names, "Great Red Spinner" can refer to more than one taxon. They're previewed below, along with 15 specimens. For more detail click through to the scientific names.

Mayfly Species Isonychia bicolor

These are sometimes called Great Red Spinners.
This is by far the most important species of Isonychia. Many angling books once split its credit with the species Isonychia sadleri and Isonychia harperi, but entomologists have since discovered that those are just variations of this abundant species.

See the main Isonychia page for more about these intriguing mayflies.
Isonychia bicolor (Mahogany Dun) Mayfly NymphIsonychia bicolor (Mahogany Dun) Mayfly Nymph View 7 PicturesThis Isonychia bicolor nymph from the Catskills displays the prominent white stripe sometimes characteristic of its species. This is the first such specimen I've photographed, because members of the same species in the Upper Midwest have a more subdued stripe (and were once thought to be a different species, Isonychia sadleri). The striking coloration on this eastern nymph is more appealing.
Collected April 19, 2006 from in
Added to Troutnut.com by on April 21, 2006
Female Isonychia bicolor (Mahogany Dun) Mayfly DunFemale Isonychia bicolor (Mahogany Dun) Mayfly Dun View 13 Pictures
Collected June 14, 2005 from in
Added to Troutnut.com by on May 26, 2006
Male Isonychia bicolor (Mahogany Dun) Mayfly SpinnerMale Isonychia bicolor (Mahogany Dun) Mayfly Spinner View 15 PicturesI got several really nice pictures of this spinner. I also collected a female on the same trip.
Collected August 9, 2006 from in
Added to Troutnut.com by on August 11, 2006

Mayfly Species Drunella grandis

These are sometimes called Great Red Spinners.
This species (or rather group of subspecies (Subspecies: Entomologists sometimes further divide a species into distinct groups called subspecies, which have two lower-case words on the end of their scientific name instead of one. The latter is the sub-species name. For example, Maccaffertium mexicanum mexicanum and Maccaffertium mexicanum integrum are two different subspecies of Maccaffertium mexicanum.)), together with Drunella doddsii, make up the famous Western Green Drake hatches. They are widespread throughout the vast Western region and can be abundant enough in many locations to provide world class angling.

It hasn't been all that many years since Western traditions and entomological "facts on the ground" began to influence the angler's lexicon heavily dominated by Eastern writers. Their initial reporting after visiting the region first popularized the phrase "Rocky Mountains answer to the popular Green Drakes of the East". This led to a false impression that lingers to this day. The reality is these giants of their family have abundant populations all over the West with no counterpart in the East, and the West does have abundant hatches of comparable Ephemeridae. The Western tradition of naming outsized Mayflies "Drakes" is the reason for what many consider a misnomer by giving it the same common name as the legendary Ephemerid of the East and surely contributed to confusion for anglers unconcerned with such subtleties.
Drunella grandis (Western Green Drake) Mayfly NymphDrunella grandis (Western Green Drake) Mayfly Nymph View 2 Pictures
Collected June 5, 2007 from in
Added to Troutnut.com by on June 28, 2011
Female Drunella grandis (Western Green Drake) Mayfly DunFemale Drunella grandis (Western Green Drake) Mayfly Dun View 3 Pictures
Collected June 29, 2007 from in
Added to Troutnut.com by on June 28, 2011
Drunella grandis (Western Green Drake) Mayfly AdultDrunella grandis (Western Green Drake) Mayfly Adult View 3 Pictures
Collected June 30, 2010 from in
Added to Troutnut.com by on June 29, 2011

Mayfly Species Timpanoga hecuba

These are sometimes called Great Red Spinners.
Timpanoga hecuba is not abundant enough, and its emergence not concentrated enough to provide great hatches, but where it is locally abundant it creates fishable action because of its large size. This species seems subject to substantial fluctuations in population densities, possibly in relation to the amount of silted habitat they prefer. When silt builds up in drought years, their numbers appear to increase. It is the largest species in the Ephemerellidae family, often rivaling Drunella grandis (Western Green Drake) in length but appearing even stouter due to its dramatic lateral (Lateral: To the side.) abdominal spines. It contains two subspecies (Subspecies: Entomologists sometimes further divide a species into distinct groups called subspecies, which have two lower-case words on the end of their scientific name instead of one. The latter is the sub-species name. For example, Maccaffertium mexicanum mexicanum and Maccaffertium mexicanum integrum are two different subspecies of Maccaffertium mexicanum.). See the Timpanoga genus hatch page for details.

There seems to be no preferred common name and anglers call them many things. Great Red Quill and Western Red Drake seem to fit best, though many refer to them as Giant Dark Hendricksons. Many fly shop reports have recently started to refer to them by their Latin species name.
Timpanoga hecuba (Great Red Quill) Mayfly NymphTimpanoga hecuba (Great Red Quill) Mayfly Nymph View 2 Pictures
Collected August 26, 2005 from in
Added to Troutnut.com by on June 28, 2011
Female Timpanoga hecuba (Great Red Quill) Mayfly DunFemale Timpanoga hecuba (Great Red Quill) Mayfly Dun View 3 PicturesThis specimen is 14 mm. Technically this is the subspecies (Subspecies: Entomologists sometimes further divide a species into distinct groups called subspecies, which have two lower-case words on the end of their scientific name instead of one. The latter is the sub-species name. For example, Maccaffertium mexicanum mexicanum and Maccaffertium mexicanum integrum are two different subspecies of Maccaffertium mexicanum.) T. h. hecuba. The Cascades, Sierras and further West is where the other subspecies (Subspecies: Entomologists sometimes further divide a species into distinct groups called subspecies, which have two lower-case words on the end of their scientific name instead of one. The latter is the sub-species name. For example, Maccaffertium mexicanum mexicanum and Maccaffertium mexicanum integrum are two different subspecies of Maccaffertium mexicanum.), T. h. pacifica is found. The Great Basin seems to have formed a barrier preventing any overlap in their distribution.
Collected September 15, 2013 from in
Added to Troutnut.com by on September 23, 2013

Mayfly Species Maccaffertium vicarium

These are sometimes called Great Red Spinners.
In the East and Midwest this is one of the most important hatches of the Spring. They are large flies which emerge sporadically, making for long days of good fishing.

This species contains the two classic Eastern hatches formerly known as Stenonema vicarium and Stenonema fuscum, the "March Brown" and "Gray Fox." Entomologists have discovered that these mayflies belong to the same species, but they still display differences in appearance which the trout notice easily. Anglers should be prepared to imitate both types.
Maccaffertium vicarium (March Brown) Mayfly NymphMaccaffertium vicarium (March Brown) Mayfly Nymph View 5 Pictures
Collected April 19, 2006 from in
Added to Troutnut.com by on April 21, 2006
Male Maccaffertium vicarium (March Brown) Mayfly DunMale Maccaffertium vicarium (March Brown) Mayfly Dun View 10 PicturesI collected this mayfly on the same trip as a female of the same species. After these photos it molted into a spinner. This is the form of Maccaffertium vicarium which anglers call the "Gray Fox."
Collected May 28, 2005 from in
Added to Troutnut.com by on May 24, 2006
Female Maccaffertium vicarium (March Brown) Mayfly SpinnerFemale Maccaffertium vicarium (March Brown) Mayfly Spinner View 7 PicturesI collected this mayfly on the same trip as a male of the same species. They are Maccaffertium vicarium mayflies of the type formerly known as Stenonema fuscom, the "Gray Fox."
Collected May 28, 2005 from in
Added to Troutnut.com by on May 24, 2006

Mayfly Species Drunella doddsii

These are very rarely called Great Red Spinners.
This species together with the Drunella grandis sub-species make up the Western Green Drake hatch. Besides being smaller, the adults are difficult to tell apart from it's larger siblings; but D. doddsi nymphs have a few peculiar traits that set them apart. D. doddsi looks much thicker in the thorax (Thorax: The thorax is the middle part of an insect's body, in between the abdomen and the head, and to which the legs and wings are attached.), has a flat frontal head margin and a unique oval disk-like ring of hairs on its ventral (Ventral: Toward or on the bottom.) surface. However, There are very few differences between the habits of these two species, and they are almost always discussed together in fly fishing books, so for many of the characteristics of doddsii, refer to the Drunella grandis page.
Drunella doddsii (Western Green Drake) Mayfly NymphDrunella doddsii (Western Green Drake) Mayfly Nymph View 12 Pictures
Collected July 17, 2011 from in
Added to Troutnut.com by on July 20, 2011
Female Drunella doddsii (Western Green Drake) Mayfly DunFemale Drunella doddsii (Western Green Drake) Mayfly Dun View 7 PicturesI still haven't got my good camera gear set up, but I wanted to get my first Alaskan bug specimen online, so I photographed this one with my point+shoot in the raft.
Collected July 8, 2007 from in
Added to Troutnut.com by on July 19, 2007

Mayfly Species Ephemera simulans

These are very rarely called Great Red Spinners.
The Brown Drakes are a favorite hatch of many in the Midwest, and they make a good showing on localized waters across the country. They are usually the first in a series of big drakes which bring large trout to the surface at twilight and into the early hours of the night.
Ephemera simulans (Brown Drake) Mayfly NymphEphemera simulans (Brown Drake) Mayfly Nymph View 10 Pictures
Collected January 31, 2004 from in
Added to Troutnut.com by on January 25, 2006
Male Ephemera simulans (Brown Drake) Mayfly SpinnerMale Ephemera simulans (Brown Drake) Mayfly Spinner View 7 Pictures
Collected June 2, 2005 from in
Added to Troutnut.com by on May 24, 2006
Top 10 Fly Hatches
Top Gift Shop Designs
Top Insect Specimens
Miscellaneous Sites