Mayfly Species Choroterpes albiannulata

This is a blackish species with white-ringed abdomen. Head blackish above with antennal flagellum pale. Thorax shining black above and below, paler around wing and leg bases; the mesepisternal area with coppery reflections. Legs dull grey, almost sooty black on the front femora of the male. Tarsi paler. Wings hyaline, a little greyish at the stigma, with hardly a suggestion of darkening at the extreme base. Veins pale brown, darker from the radius forward. All cross veins faint, those of the stigmatic area simple, erect, and distant.

Abdomen brownish at the ends, grey on segments 2 to 6, paler beneath. The joinings of the middle segments are narrowly white above and below, giving the abdomen a distinctly ringed appearance. There is a row of diffuse blackish dots on the abdominal spiracles. Forceps, penes, and tails greyish, the last narrowly ringed with brown on the joinings of the segments.