The giant Salmonflies of the Western mountains are legendary for their proclivity to elicit consistent dry-fly action and ferocious strikes.
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.
Only the nymph of this species is known. The nymph lacks both the dorsal and lateral spines on the mesonotal shield. Frontal projection short, genae not produced into spine-like processes. From other nymphs of this genus thus far described, it is distinguishable at once by the total lack of both dorsal and lateral mesonotal spines. It is not probable that these spines would be present in the fully mature nymph, although only immature specimens are known as yet.*