Ephemeridae
Guides
Ephemera blanda
common burrower mayfly
Ephemera blanda is a species of burrower mayfly in the family Ephemeridae, characterized by its fossorial lifestyle in aquatic sediments. The species inhabits running waters in the southeastern Nearctic region. As with other members of the genus Ephemera, adults are short-lived and primarily focused on reproduction.
Ephemera simulans
Brown Drake
Ephemera simulans is a burrowing mayfly species in the family Ephemeridae, commonly known as the Brown Drake. It is widely distributed across North America, particularly common in the Rocky Mountains, Midwest, and Great Lakes region. The species is economically significant in recreational fly fishing, where both nymph and adult stages are imitated with artificial flies. Nymphs inhabit sand and silt substrates of lakes and streams, emerging as adults primarily at night from mid-June to mid-July.
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.
Hexagenia bilineata
Emergent Mayfly
Hexagenia bilineata is a burrowing mayfly native to the Upper Mississippi Valley of North America. The aquatic nymphs construct U-shaped burrows in mud and silt, filtering organic detritus for food. Adults emerge synchronously in enormous numbers during summer evenings, creating spectacular swarms that have caused documented traffic hazards and infrastructure damage. The species exhibits mixed voltinism, with some populations completing development in one year while others require two years.
Hexagenia orlando
Florida Hex
Hexagenia orlando is a burrower mayfly in the family Ephemeridae, described by Traver in 1931. The species is endemic to North America, with the common name "Florida Hex" suggesting a primary association with Florida. As a member of the genus Hexagenia, it exhibits the subterranean burrowing habits characteristic of this group during its nymphal stage. Adult mayflies in this genus typically emerge in synchronized swarms.