1.            Caudal filaments with dark band near middle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

               Caudal filaments uniformly shaded or at most only gradually changing . . . . . . . . . . . . . . 3

2.             Darker well marked abdominal terga with 2 large submedian pale areas often kidney                          shaped . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Baetis flavistriga
 

               Darker well marked abdominal terga with 3 posterior round pale areas, middle spot often                smaller than laterals  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Baetis intercalaris

3.            Pronotum with 2 submedian dark bilobed marks; abdominal sterna with robust setae. . . . .                . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Baetis tricaudatus

 

              pronotum without dark bilobed marks; abdominal sterna without robust setae. . . . . . . . . . .                . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  Baetus brunneicolor

 

Baetis rusticans is not known as the nymph. Baetis armillatus


 

 

 

 

 

 

Key to Ohio Baetis Nymph Species

[Home], [Back to Mayfly Nymph Families][Back to the Baetidae Family]
Mayflies of Ohio
(Modified from Morihara & McCafferty, 1979)