Mayfly Species Caudatella edmundsi

Cerci 5-6 mm; terminal filament 8-9 mm. General color uniformly light brown. Head without occipital tubercles; labrum hairy and deeply emarginate (fig. 22); maxillae with very small palpi or palpifer (fig. 20). Legs short and thick, all segments with short heavy spines and only scattered hairs; tarsal claws with double row of denticles, anterior row with 10-14 small denticles and posterior row with 9-12 larger denticles (fig. 21). Abdomen with conspicuous, paired dorsal submedian tubercles on segments 1-10 as in fig. 27; width between bases of tubercles narrow on segment 1, gradually increasing in width to segment 5, narrowing again to segment 10, tubercles barely discernible on segment 10; sterna 4-8 with pale, sometimes obscure, brown dashes on lateral margins (fig. 10). Caudal filaments light brown, lateral cerci 55% to 65% as long as terminal filament.