The giant Salmonflies of the Western mountains are legendary for their proclivity to elicit consistent dry-fly action and ferocious strikes.
In 4 records from GBIF, adults of this species have been collected during April (75%) and June (25%).
In 2 records from GBIF, this species has been collected at elevations of 443 and 896 ft.
Current speed: Medium is best; slow is good; slow microhabitat in fast stretches are okay
Substrate: Gravel, detritus
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.
This is a blackish species with a brown abdomen that is only a little paler in the middle. Top of head and thorax shining black, only the sutures on the sides paler; dorsum of the first abdominal segment also blackish. Legs brown including the tarsi, paler brown beyond the knees. Wings sub-hyaline with brown veins and darker brown wing roots. Costal cross veins faint and rather numerous; those of the stigmatic region long, sinuate and crowded, but little conjoined. The abdomen is nearly uniform brown, only the base of segments 3-5 showing a suggestion of pale rings; and the apical segments are only a little darker on the dorsum. Forceps yellowish brown; the 2nd joint twice as large as the 3rd. Penes appressed, half as long as the first joint of the forceps. The sperm ducts terminate before the apex between a rounded inner lobe and an outer triangular tooth that is turned sharply laterally; below this the outer margin of the penis is suddenly widened and the basal portion parallel-sided (see fig. 135). Tails uniform pale brown.