Mayfly Species Callibaetis pretiosus (Speckled Duns)

A brown species; cross veins of fore wing rather numerous; marginal intercalaries occur singly; male not known.

Body of female brown. Two narrow white stripes on the thoracic notum. Legs pale, tips of tibiae dark, also the tarsal joints. Wings hyaline; veins and cross veins mostly white, but the longitudinal veins with some dark marks. Costal vitta consists of a “fairly broad brown stripe from base to tip, its hind margin sinuate with four projections, four hyaline spots in the subcostal area before the middle, about five pale spots on costal margin before the middle, and several more or less connected beyond.” Along the hind margin are five or six faint irregular clouds. Hind wing much as in Callibaetis floridanus. Abdomen brown, with darker spots on the sides.