Mayfly Species Baetis brunneicolor (BWOs)

Abdominal tergites of male imago deep brown; genitalia of the Baetis intercalaris type, the tubercle on the inner margin of the first forceps joint well developed.

Turbinate eyes large, deep brown in color; the stalk rather short, and shaded with yellow. Head and thorax deep blackish brown. The lateral anterior margin of the mesonotum, the pleural suture and the lateral extensions of the mesosternum shaded with paler brown. Rear portion of the mesothorax with slight reddish brown markings. The median dorsal projection of the metathorax is cream-colored. Legs pale yellowish brown, the fore legs deeper in color, with smoky shading at the apex of the tibiae. Wings hyaline, venation pale. Strong granulations between the cross veins of the stigmatic area of the fore wing. Intercalaries of the first interspace much longer than those in the second space; all intercalaries well developed. Hind wing large and broad, the third vein well developed. Between the second and third veins are two marginal intercalaries; often another intercalary is present between veins 1 and 2.

Abdominal tergites 2-6 deep brown with faint ruddy tinges, and obsolescent pale submedian dashes anteriorly. Tergites 7-10 similar to the basal ones; sternites pale yellowish brown. Forceps of the intercalaris type, the inner tubercle of the first joint well developed.