Burrowing-mayfly
Guides
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.
Ephoron album
Say's Burrowing White Mayfly, White Fly
Ephoron album is a burrowing mayfly native to eastern and central North America, notable for synchronized mass emergences ('superhatches') involving millions of individuals in late summer evenings. Adults have pale milky-white wings and live less than 24 hours without feeding. Nymphs inhabit silty riverbeds and develop for several months to one year before emergence. The species was first described by Thomas Say in 1823 during the Long expedition to the Mississippi headwaters.
Ephoron leukon
white fly
Ephoron leukon, commonly known as the white fly, is a species of pale burrower mayfly in the family Polymitarcyidae. Nymphs are burrowing and inhabit tubular burrows associated with stones in river rapids, particularly in fine silt deposits. The species undergoes dramatic morphological changes during early nymphal development, including specialized mouthpart modifications for filter feeding and progressive elaboration of abdominal gills.
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 limbata
Giant Mayfly, Golden Mayfly, Big Michigan Mayfly, Great Leadwing Drake, Fishfly
Hexagenia limbata is a large burrowing mayfly native to North America, widely distributed across lakes and slow-moving rivers. Nymphs construct U-shaped burrows in muddy substrates and serve as important prey for fish and other aquatic predators. Adults emerge in synchronized mass events known as "hatches," living only 1–3 days without feeding, solely to mate and reproduce. The species is economically significant to sport fishing and serves as a bioindicator of clean freshwater ecosystems.
Hexagenia rigida
Great Olive-winged Drake
Hexagenia rigida is a burrowing mayfly (Ephemeroptera: Ephemeridae) native to North America. As a member of the common burrower mayfly genus, it spends most of its life as an aquatic nymph in lake and reservoir sediments, with adults emerging synchronously in large swarms. The species has a multi-year life cycle, typically requiring 3-4 years to complete development from egg to adult in northern climates. Laboratory studies indicate that larval growth and mortality are significantly influenced by food availability and density, with food limitation increasing size variation and mortality rates.
Tortopsis primus
Manitoba white burrowing mayfly
Tortopsis primus is a species of burrowing mayfly in the family Polymitarcyidae, described by McDunnough in 1924. It is commonly known as the Manitoba white burrowing mayfly. The species belongs to the order Ephemeroptera, an ancient group of aquatic insects with aquatic immature stages and short-lived winged adults. As a member of Polymitarcyidae, it exhibits the family characteristic of burrowing habits in its nymphal stage.
Tortopsis puella
Tortopsis puella is a species of burrowing mayfly in the family Polymitarcyidae, originally described by Pictet in 1843. It belongs to a genus characterized by fossorial (burrowing) larvae that inhabit sandy or muddy substrates in freshwater environments. The species is known from the Nearctic region, with records from North America.