The famous nocturnal Hex hatch of the Midwest (and a few other lucky locations) stirs to the surface mythically large brown trout that only touch streamers for the rest of the year.
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.
A small species with untinted wings; a spine on inner margin of penes only; dark mid-ventral ganglionic marks.
Head light wood-brown; bases of antennae ochreous; eyes dull greenish in living insect, almost contiguous. Often slight reddish or purplish shading next to the eyes. Thorax light brown; yellowish ochre shading on mesonotum anterior to scutellum, and on the anterior portions of the metanotum. Legs pale brown. Wings hyaline, untinted. Cross veins “in the basal half pale, indistinct, darker and better defined in the apical area, especially the costal ones” (McD.). Abdominal segments 2-7 hyaline; tergites light brown on posterior half or third, the postero-lateral corners darker; anterior portions of each tergite pale hyaline. Sternites pale with brown oval ganglionic markings. Segments 8-10 opaque; tergites light brown, sternites deep ochreous. Penes with a short spine on inner margins only (see fig. 103). Tails dirty white.
This species is allied to Cinygmula mimus and Cinygmula ramaleyi, by the type of genitalia. Differs from both of these in structural characters of genitalia and in the untinted wings.