1. Apex of tergum 10 completely dark (Fig 2.1.1.1) . . . . . . . . . . . Agnetina annulipes
Apex of tergum 10 light (Fig 2.1.1.2). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Posterior 1/3 to 1/2 of Ab1-9 terga darkly pigmented (Fig. 2.1.1.3), occasionally specimens from soft (dark, coffee-colored) water, completely dark. Arms of M-line on head directed essentially laterad (Fig, 2.1.1.4); dark pigment of tergum 10 usually continuous, narrowed over most of tergum (Fig.2.1.1.3). . . . Agnetina capitata
Anterior 1/3 to 1/2 of Ab1-9 terga darkly pigmented (Fig.2.1.1.5), often fragmented on some segments and bissected by longitudinal pigment lines. Arms of M-line on head directed posterolaterally (Fig.2.1.1.6); dark pigment of tergum 10, when present, usually divided mesally, but covering most of tergum 9 (Fig.2.1.1.7). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Agnetina flavescens
Key to the Genera of Ohio Agnetina Nymphs
