Isonychia rufa is a species of brushlegged mayfly in the family Isonychiidae and the bicolor group.

[1] It is found in central North America, from southern Manitoba to Oklahoma.

[2][3][4][5][1] Isonychia rufa is commonly found in larger rivers and streams from the Mississippi drainage.

[1] Isonychia rufa can be distinguished from other species in the bicolor group through certain characteristics present in male imago.

These include: whiteish and light yellowish veins in the forewing hyaline,[1] dorsal penes with a relatively prominent basal swelling which forms lateral and apical ridges,[1] bright red to reddish orange brown abdomen,[1] and stigmatic cross veins (usually anastomosed).