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 female imago of this species is known. Body uniform light brown. Hind wing with two veins only; the third entirely wanting, according to the original description. Costal projection present, quite prominent.
Described as B. minimus
Body length 5 mm, wing length 7.5 mm
Only the female imago is known, hence the position of this species in reference to others of the genus is uncertain. Species said to be much like moffati (now a synonym of Baetis tridcaudatus), but differing in the small size of the body in relation to the fore wing, and of the hind wing in relation to the size of the fore wing. Hind wing rather small (0.8 mm.), the third vein present but very faint; no intercalaries. Costal projection present near the base of the hind wing, moderately developed. No color characters are given.