Tiny Baetis mayflies are perhaps the most commonly encountered and imitated by anglers on all American trout streams due to their great abundance, widespread distribution, and trout-friendly emergence habits.
In 2 records from GBIF, adults of this species have been collected during September (50%) and May (50%).
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 rather small species; abdomen yellowish, lateral stripes dark brown; a few small dark spots in disc of hind wing, its outer margin very narrowly purplish.
Head largely purplish; eye golden brown above; eyes rather large, separated by space less than one diameter of eye. Pronotum light tan, usually purplish in median area; lateral stripes dark purplish brown. Mesonota and metanota yellowish brown; brown spot in center of posterior portion of former, and lateral and posterior margins golden brown with creamy markings; creamy markings centrally and posteriorly on metanotum. Pleura yellowish brown with creamy markings. Median area of mesosterna and metasterna pale reddish brown; laterally golden brown. Fore coxa and trochanter dark brown; femur and tibia dark red-brown, joinings darker; basal and distal tarsal joints, and distal portions of middle joints, purplish brown. Middle and hind legs yellow; joinings of tibia, tarsus and all tarsal joints, as well as claws and distal tarsal joints, purplish brown. Costal margin of fore wing reddish brown. Longitudinal veins of both wings golden brown, cross veins purplish black; a few cross veins of fore wing narrowly margined, but no dark spots; in hind wing, a few small dark spots in disc, the outer margin very narrowly purplish.
Abdomen yellow to light tan, deep yellow apically. A greyish or blackish middorsal line on all tergites. On 1-7 the oblique lateral stripes arise at the antero-lateral angles, extending backwards to the median stripe on the posterior margin; except on 7, these stripes are narrower posteriorly. On the basal and middle tergites, narrow dark stripes extend along the anterior margin; posterior margins dark brown; hence the pale areas on each side are largely surrounded by dark margins. Ganglionic area of each sternite purplish brown; on sternite 9, a median orange triangle attains the anterior margin; the lateral margins of similar triangles are faintly indicated by slightly wavy brown lines on sternites 1-8. Sternite 1 may show two pale round spots near the center, one on each side; the following sternites may show traces of these pale dots. Basal tail joints light brown distally, yellow at base; at tip, joints light brown, joinings black; in remainder of tail, joints dark red-brown, joinings darker, and a narrow yellow ring at base. Genitalia of the carolina type (now a synonym of Hexagenia limbata), quite slender. Forceps base and basal joint of forceps amber brown with creamy markings; distal joints light purplish brown.