Ephemerellid
Guides
Ephemerella
Hendricksons, Sulphurs, Pale Duns
Ephemerella is a genus of spiny crawler mayflies comprising approximately 19 described species. Nymphs are characterized by their distinctive defensive posture, curling the abdomen upward in a scorpion-like manner when disturbed. The genus has a widespread distribution across North America and Europe, with species occupying diverse lotic freshwater habitats. Several species, including E. subvaria and E. ignita, have been subjects of detailed life history studies.