Ohio Mayflies

1.             Lamellate gills present on abdominal segments 3-7 (Fig.1.1). . . . . . . . . . . . . . . . . . . . . 2

                Lamellate gills present on abdominal segments 4-7 (Fig.1.2). . . . . . . . . . . . . . . . . . . . . 5

2.             Leading margin of forefemora usually armed with conspicuous tubercles (jagged or                 roughened with spurs or spines)(Fig.1.3). . . . . . . . . . . . . . . . . . . Drunnella cornutella

                Leading margin of forememora without such tubercles, without large tubercles on dorsum                 of head, thorax, and abdomen, abdominal sterna without disk of long hair. . . . . . . . . . 3

3.            Caudal filaments with whorls of spines at apex of each segment, otherwise with only sparse                 setae or none; axillary palps reduced to one-half or less the length of the galea-lacinia . . . .                 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

                Caudal filaments with or without whorls of spines at apex of each segment, apical half of                 caudal filaments with long intersegmental setae extending laterally (Fig.1.5); maxillary                 palps well developed, usually two-thirds or more the length of the galea-lacinia (Fig.1.16).                 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..Ephemerella

4.             Abdominal terga without paired, sumedian tubercles; maxillary palpi absent; legs brown                 with darker brown tibial and tarsal bands; tarsal claws long and narrow, with 8 to 10                 denticles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Teleganopsis deficiens

                Abdominal terga with paired, submedian tubercles; maxillary palpi present; legs and tarsal                 claws variable. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Saratella

5.             Abdominal tergum 9 greatly elongated compared to tergum 7 (Fig.1.21); claws with                 denticles (Fig.1.22); maxillae without palp (Fig.1.23). . . . . . . . . . . . . . . . . Eurylophella
                Abdominal tergum 9 not greatly elongated compared to tergum 7 (Fig.1.24); claws without                 denticles (Fig.1.25); maxallae with palp (Fig.1.26). . . . . . . . . . . . . . . . . . . . . . Dannella

Key to Ohio Ephemerellidae Nymph Genera

[Home], [Back to Mayfly Nymph Families]