1. Lacinia unidentate (Fig. 2.3.1). . . . . . . . . . . . . . . . . . . . . . . . . . . Isoperla (in part)
Lacinia bidentate (Fig. 2.3.2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2
2. Abdomen with longitudinal pigment bands (Fig. 2.3.3) . . . . . . .Isoperla (in part)
Abdomen without longitudinal pigment bands (Fig. 2.3.4) . . . . . . . . . . . . . . . . . . . 3
3. Inner lacinial margin with a low knob below subapical tooth (Fig. 2.3.5) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Malirekus iroquois
Inner lacinial margin without a low knob below subapical tooth (Fig. 2.3.6). . . . . . . 4
4. Occellar region transverse by dark band connecting lateral ocelli and eyes but not
covering anterior ocellus (Fig. 2.3.7). . . . . . . . . . . . . . . . . . . . . . . . . Clioperla clio
Occellar triangle more or less completely covered by dark pigment (Fig. 2.3.8). . . . 5
5. Mesosternal Y with basal stem and fork (Fig. 2.3.9) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Cultus decisus decisus or Cultus verticalus
Mesosternal Y without stem and fork (Fig. 2.3.10) . . . . . . . . . . .Diploperla robusta
Hydroperla crosbyi, Hydroperla fugitans; Helopicus nalatus and Helopicus subvarians are not reported for Ohio but may be found in larger rivers.
Key to the Genera of Ohio Perlodidae Nymphs
