Mayfly Species Plauditus virilis

Head: Pale with two pairs of paramedial irregular brown stripes over vertex and frons.

Thorax: Notum mostly pale with small dark brown spots, dots and dashes; veins on wing pads traced with brown; femora with two incomplete dark bars, one towards the base and one nearer the apex; tarsal claws with long pectinations.

Abdomen: Segments 1, 2, 6, and 7 mostly dark above, others mostly pale; row of submedian dark spots about the middle of each dorsum; venter of each segment with four indistinct small submedian dots, (anterior pair sometimes obsolescent) and venters of 5-7 suffused with grey; lateral caudal filaments pale with a dark band less than halfway out and a dark tip, median filament about as long as the width of a lateral filament at the base; gills on segments 1-7, without conspicuous tracheae.

Much like the female nymph of P. dubium though larger; the dorsum of the abdomen with a row of median pale areas at the anterior border of the segments and a submedian row of pale areas at the posterior border of the segments, and further laterally another row of pale areas; these pale areas more extensive than in P. dubium.

Abdominal tergites 2-6 of male imago hyaline; faint ruddy tinges on posterior margins; two small red submedian dots on anterior portion of each.

Turbinate eyes, in dried specimen, large, oval, deep reddish brown. Head blackish. Antennae likewise blackish. Thorax shiny black; a pale yellow streak anterior to wing base, along antero-lateral margin of mesonotum; sutures of pleura and sternum slightly marked with paler. Fore femur and base of tibia smoky yellow; tarsus and remainder of tibia pale whitish. Middle and hind legs whitish; a median band and apex of femur pale purplish-red. Wings hyaline. Abdominal segments 2-6 whitish hyaline; tergites faintly tinged with ruddy on the segmental incisures; two minute red submedian dots on the anterior portion of each tergite. Tergites 7-10 chocolate brown; sternites pale, opaque, 7 and 8 with considerable ruddy shading. On sternites 5 and 6 there is a faint mid-ventral ruddy dot.

The presence of the dorsal submedian red dots and the mid-ventral dots on sternites 5 and 6 distinguishes this species from others allied to it.