Mayfly Species Ameletus shepherdi (Brown Duns)

A small species with pale whitish abdomen and amber-tinted wings.

Head and thorax light reddish brown. Mesonotum yellowish, its anterior portion reddish margined with white; scutellum pale whitish, its postero-lateral margins dark reddish brown. Pleura yellowish red; sutures dark red-brown, intersegmental spaces whitish. Legs pale; tibia and tarsus of fore leg amber yellow, femur and middle and hind legs whitish. Wings hyaline, distinctly tinged with amber, most noticeably in the stigmatic area of the fore wing and the entire hind wing. Venation pale reddish brown to amber in the male, dark reddish brown in the female. Stigmatic cross veins anatomosed.

Abdominal segments 1, and 7-10, opaque, pale reddish to yellowish red; dorsum of posterior segments darker than venter. Intermediate segments whitish with faint tinge of pale yellowish red on the dorsum; semi-translucent, and with no distinct markings. Posterior margins and ganglionic areas opaque whitish. Dorsum of female pale reddish brown. Tails amber yellow, paler at tips. Genitalia amber yellow. Distal portion of penes directed outward. No spine, but a blunt thumb-like projection, on the inner margin of the penes. Tubercle on the inner distal margin of the forceps base blunt, quite prominent. Apical margin of forceps base very shallowly excavated (see fig. 117).

Nymph without distinct dark markings. Last two segments of abdomen dark reddish brown; posterior margins of all segments, also the lateral extensions, narrowly reddish brown. Postero-lateral spines on segments 2-9, very short on 2. A dark reddish brown band across the middle of the tail.