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.
Source: Epiproct And Dorsal Process Structure In The Allocapnia Forbesi Frison, Allocapnia Pygmaea (Burmeister), And Allocapnia Rickeri Frison Species Groups (Plecoptera: Capniidae), And Inclusion Of Allocapnia Minima (Newport) In A New Species Group
Male epiproct. Apical segment of upper limb ca. 303 µm long, and armed on the apical ca. 186 µm with dense patch of wave-like spikes (Figs. 85 - 88); apical segment ca. 145 µm wide at base, gradually narrowed to a bluntly rounded tip. Basal segment of upper limb ca. 541 µm long and ca. 85 µm wide near mid-length; basal segment bears a shallow, longitudinal groove in basal half. Greatest width of lower limb about as wide as apical segment of upper limb, but not clearly projecting beyond margins of apical segment. Male tergal process. Prominent raised bilobed structure on abdominal tergum 8 (Figs. 89 - 90); process on tergum 8 ca. 256 µm wide and covered with scale-like structures. Lobes of tergum 8 process small, ear-like, directed caudally and obliquely oriented on segment; notch ca. 140 µm.