Mayfly Species Pentagenia vittigera

Mesonotum and dorsal abdominal stripe duller and not quite as deep in color as in Pentagenia robusta; venation pale except on costal margin; no black lines on sternites.

Face yellowish; ocelli heavily black-ringed at base; antennae pale reddish, tip of filament white; eyes of living insect “‘yellowish on upper 3/4 and dark ferruginous on lower 1/4’’ (Walsh). In alcohol, eyes appear dark bluish grey. Pronotum yellowish, with a median purplish brown band. Mesonotum purplish to blackish brown; several black longitudinal streaks on anterior and median areas; sutures narrowly black; paler areas above wing root and on each side anterior to scutellum. Metanotum purplish brown, posterior margin black. Pleura yellowish; a dark oblique streak anterior to middle and hind leg. Sternum pale yellowish. Legs yellowish. Fore tibia purplish at tip (according to Walsh, at base also); tarsal joinings same color, also apical margins of distal tarsal joints of middle and hind legs.

“Wings hyaline; veins and cross veins fine, subequal, hyaline, except on the costa, where they are coarse, the first vein fuscous at base, yellowish at tip; the second and third yellowish throughout; the costal cross veins fuscous at base, becoming yellowish towards the tip of the costa; in the hind wings two costal veins, with their connecting cross veins, are pale fuscous” (Walsh). In specimens we have examined, all veins of hind wing are colorless. In addition, there may be four dark dots on the fore wings, more or less distinct in different individuals, sometimes obsolescent. Of these Walsh says, under P. quadripunctata; ‘four distinct fuscous dots, each surrounded by a slight cloud and conspicuous to the naked eye, on the front wings, extending in a slightly curved line from the middle of the costa to the center of the disc; viz. one on the second vein of the costa, and one on the fourth, sixth and ninth veins respectively from the costal margin.

Lateral margins of abdominal tergites yellowish white; sternites pale yellowish white, unmarked, 8 and 9 rather deeper yellow. Dorsally a wide purplish black median band occupies a large portion of each tergite, its lateral margin irregular, widest near each anterior margin. Within this dark band pale oblique submedian streaks extend backward from the anterior margin to about the middle of each tergite; very faint traces of a narrow pale mid-dorsal line may be present. Genitalia and tails wholly pale, unmarked. Genitalia as in fig. 78.

This is a more slender species than Pentagenia robusta, with paler venation and tails, and no dark ventral markings.