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.

I caught a nice brookie a few weeks earlier in this pool at the junction of a split channel in the stream. The huge fallen tree is great cover.

From the Mystery Creek # 23 in New York

Stream photos

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Lateral view of a Coleoptera (Beetle) Insect Larva from Sears Creek in Washington

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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.

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Mayfly Species Rhithrogena manifesta

Very little has been written about this species and I have found no accounts of fishable hatches.

Where & when

Time of year : June-July

In 5 records from GBIF, adults of this species have been collected during July (80%) and June (20%).

In 2 records from GBIF, this species has been collected at elevations of 23 and 26 ft.

Species Range

source

Map of specific collection sites

Nymph biology

Current speed: Fast

Substrate: Gravel

Physical description

Most physical descriptions on Troutnut are direct or slightly edited quotes from the original scientific sources describing or updating the species, although there may be errors in copying them to this website. Such descriptions aren't always definitive, because species often turn out to be more variable than the original describers observed. In some cases, only a single specimen was described! However, they are useful starting points.

Male Spinner

Described in Needham et al (1935) as Heptagenia manifesta

Body length: 4-7 mm
Wing length: 5-7 mm

Mesonotum piceous; abdominal tergites ferruginous; venation pale hyaline, bases of three main costal veins fuscous at base; type of genitalia uncertain.

Eyes brown above, the lower portion fuscous. Thoracic notum generally piceous. Legs pale greenish; femora with a narrow median band, the knee fuscous; apex of fore tibia, tips of tarsi, and joinings of fore tarsus, fuscous. Wings hyaline; venation pale greenish hyaline, except the basal third of costa, subcosta and radius, and occasionally their tips also, which are fuscous. Abdominal tergites ferruginous, the posterior half or third of each somewhat piceous. Forceps pale; tails uniformly whitish; penes blackish, according to Hagen.

Start a Discussion of Rhithrogena manifesta

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.
Needham, James G., Jay R. Traver, and Yin-Chi Hsu. 1935. The Biology of Mayflies. Comstock Publishing Company, Inc.