Nymphs prefer riffles where the substrate consists of decomposed vegetation. They are good swimmers with long thin abdomens, and long legs. Baetis hatches sometimes overlap both Epeorus pleuralis, and Ephemerella subvaria. Duns display a very small (dwarfed) hind wing. Some female spinners of the Baetis species dive under water to lay their eggs. Female duns are olive, males are gray olive. Female spinners are light tanish olive, male spinners are gray olive.