Hexagenia
Guides
Hexagenia atrocaudata
Lake Hex
Hexagenia atrocaudata is a burrowing mayfly species in the family Ephemeridae, known from North American lakes and rivers. As a member of the common burrower mayflies, it spends the vast majority of its life as an aquatic nymph in bottom sediments, emerging as a short-lived winged adult for reproduction. Adults lack functional mouthparts and do not feed. Mass synchronous emergences can occur, producing swarms that attract fish and anglers alike. The species serves as an important indicator of clean freshwater ecosystems and provides substantial food resources for aquatic and terrestrial predators.