Mayflies
Order Ephemeroptera
Among the most ancient winged insects. Adults live only hours to days, just long enough to mate. Their aquatic nymphs are important indicators of water quality.
Species in this Order (60)
American Sand Mayfly
Dolania americana
Holds the record for the shortest adult lifespan of any insect — females live less than five minutes...
Angler's Curse Mayfly
Caenis rivulorum
A tiny mayfly nicknamed for frustrating anglers who cannot imitate it on hook. Nymphs burrow in fine...
Arctic Mayfly
Baetis bundyae
A small, delicate mayfly with transparent wings and two long tail filaments. Nymphs are agile swimme...
Australian Giant Mayfly
Atalophlebia australis
One of the largest Australian mayflies, found in clean streams of southeastern Australia. Nymphs hav...
Autumn Dun
Leptophlebia marginata
A dark-winged mayfly that emerges in spring despite its common name. Nymphs inhabit slow-flowing sec...
Blue Quill
Paraleptophlebia guttata
A delicate spring-emerging mayfly with bluish-gray body coloring. Nymphs prefer riffles with abundan...
Blue-Winged Olive
Baetis tricaudatus
A small olive-colored mayfly with distinctive bluish-gray wings, abundant in clean streams across No...
Brown Drake Mayfly
Ephemera simulans
A large brownish mayfly with mottled wings that produces dramatic evening hatches on trout streams. ...
Brushleg Mayfly
Isonychia bicolor
A large, fast-swimming mayfly with forelegs fringed with bristles for filter feeding. Nymphs inhabit...
Burrowing Mayfly
Hexagenia limbata
Creates massive synchronized emergences so dense they appear on weather radar. Billions emerge simul...
Burrowing Mayfly
Ephemera vulgata
A common European mayfly with spotted wings and a yellowish body. Nymphs construct U-shaped burrows ...
Caenis Mayfly
Caenis horaria
One of the smallest mayflies, often called the 'angler's curse' because trout feed on them selective...
Cahill Mayfly
Stenacron interpunctatum
A cream-to-tan colored mayfly found throughout eastern North America. It is named after the classic ...
Claret Dun Mayfly
Leptophlebia vespertina
A dark-winged mayfly that emerges in the evening over still and slow-moving waters....
Common Mayfly
Ephemera danica
Adults have no functional mouths and live only 1-3 days. Massive synchronized emergences called "hat...
Dark Blue Quill
Paraleptophlebia mollis
A small dusky-winged mayfly of Appalachian headwater streams. Nymphs are slow crawlers among leaf de...
Dark Hendrickson Mayfly
Leptophlebia cupida
A dark-bodied spring mayfly important to trout anglers in the Northeast. Nymphs inhabit leaf packs a...
Drake Mackerel Mayfly
Ephemera glaucops
A large European burrowing mayfly with distinctive dark markings on its wings. It emerges in synchro...
Flat-headed Mayfly
Epeorus assimilis
A stream-dwelling mayfly nymph with a flattened body for clinging to rocks in rapids....
Flat-headed Mayfly
Ecdyonurus venosus
A large flat-bodied mayfly found clinging to stones in fast European rivers. Its distinctly flattene...
Giant Michigan Mayfly
Hexagenia bilineata
A large burrowing mayfly with two dark stripes on its thorax. Nymphs dig into soft clay and silt bot...
Green Drake Mayfly
Ephemera guttulata
A large and strikingly beautiful mayfly with mottled wings that emerges in late spring. Its hatches ...
Indian Olive Mayfly
Baetis conservatus
A small olive-colored mayfly found in Himalayan streams and foothill rivers. Nymphs are agile swimme...
Iron Blue Dun
Baetis muticus
A small dark mayfly that hatches prolifically on cool overcast days. Nymphs are found clinging to st...
Japanese Burrowing Mayfly
Ephemera japonica
A large burrowing mayfly native to Japanese rivers and streams. It emerges in large numbers during e...
Labrador Minnow Mayfly
Baetis labradoriensis
A small mayfly found in cold northern streams with rapid currents. Nymphs cling to submerged stones ...
Large Dark Olive Mayfly
Baetis rhodani
The most common European mayfly, emerging year-round in many rivers. It is a small olive-brown speci...
Large Dark Olive Mayfly
Baetis atrebatinus
A medium-sized olive-brown mayfly found in clean European rivers and streams. It emerges in spring a...
Light Cahill Mayfly
Heptagenia solitaria
A pale-colored mayfly highly prized by fly fishers for imitating hatches. Nymphs prefer moderate cur...
Long-Tailed Mayfly
Palingenia longicauda
The largest European mayfly with body and cerci reaching over 120 mm. Its spectacular mass hatches o...
Mahogany Dun
Isonychia harperi
A large reddish-brown mayfly with impressive filter-feeding forelegs. Nymphs prefer moderate to fast...
March Brown Mayfly
Rhithrogena germanica
A spring-emerging mayfly with a brownish body and two tails, historically important to European fly ...
Mountain Flathead Mayfly
Cinygmula ramaleyi
An alpine mayfly restricted to high-elevation cold streams in the Rocky Mountains. Nymphs feed on di...
New Zealand Mayfly
Deleatidium lillii
The most abundant and widespread mayfly genus in New Zealand. Nymphs dominate the invertebrate fauna...
Olive Drake Mayfly
Ephemera lineata
A large burrowing mayfly with distinctive mottled brown wings. Nymphs excavate U-shaped burrows in s...
Pale Evening Dun
Heptagenia adaequata
A flat-bodied mayfly whose nymphs press tightly against rocks in swift currents. Adults emerge at du...
Pale Morning Dun
Heptagenia elegantula
A delicate pale yellow mayfly of western streams that emerges in morning hours. Nymphs cling flat ag...
Pale Morning Dun
Ephemerella excrucians
A small pale yellowish mayfly that hatches in large numbers on western North American streams during...
Pink Lady Mayfly
Epeorus vitreus
A pale pinkish mayfly of eastern North American streams with a distinctly two-tailed nymph. Adults h...
Pond Olive Mayfly
Cloeon dipterum
One of the few mayflies that breeds in still water including garden ponds and rain barrels. Unusuall...
Purple Dun
Paraleptophlebia adoptiva
A small dark mayfly with purplish-gray wings found in eastern streams. Nymphs crawl among submerged ...
Quill Gordon Mayfly
Epeorus pleuralis
A medium-sized flat-bodied mayfly that clings to rocks in fast Appalachian streams. It is one of the...
Small Amber Spinner
Caenis macrura
A tiny mayfly whose amber-colored spinners fall to the water in dense clouds. Nymphs live among fine...
Small Minnow Mayfly
Callibaetis ferrugineus
A mottled brown mayfly common in still waters across North America. Nymphs are excellent swimmers th...
Small Spurwing Mayfly
Centroptilum luteolum
A tiny, elegant mayfly with a distinctive spur on its hindwing. It is widespread in European streams...
Small Square-Gilled Mayfly
Caenis luctuosa
A minute mayfly with distinctive square-shaped gills on its nymphs. Adults swarm in enormous numbers...
South African Prong-Gill Mayfly
Adenophlebia auriculata
A mayfly endemic to southern African mountain streams. Nymphs have distinctive forked gills used for...
South American Giant Mayfly
Campsurus major
A large tropical mayfly found in South American rivers and floodplains. Males have distinctive elong...
Spiny Crawler Mayfly
Ephemerella subvaria
A mayfly important to fly anglers and known as the Hendrickson in fishing culture....
Spiny Crawler Mayfly
Drunella grandis
A large western North American mayfly with distinctively spiny nymphs. Adults emerge in early summer...
Sulphur Mayfly
Ephemerella dorothea
A small pale yellow mayfly that produces reliable evening hatches on eastern North American streams....
Trico Mayfly
Tricorythodes minutus
A tiny mayfly whose dense morning spinner falls are legendary among fly anglers. Despite its small s...
Trico Mayfly
Tricorythodes stygiatus
A tiny mayfly that forms enormous morning spinner falls over calm streams and rivers. Males have dis...
Velvet Ameletid Mayfly
Ameletus velox
A swift-swimming mayfly of headwater streams known for its velvety-textured nymphal cuticle. Adults ...
Western Ameletid Mayfly
Ameletus cooki
A streamlined mayfly found in cold mountain streams of the Pacific Northwest. Nymphs are agile swimm...
Western Iron Dun
Epeorus longimanus
An iconic eastern mayfly that signals the start of spring fly-fishing season. Nymphs have only two t...
White Miller Mayfly
Ephoron virgo
A white-bodied European mayfly that emerges in enormous synchronized swarms at dusk. Females are uni...
White-Gloved Howdy
Isonychia sadleri
Named for the white tips of its forelegs resembling gloves. Nymphs are powerful swimmers found in fa...
Yellow Drake Mayfly
Ephemera lutea
One of the largest mayflies in eastern North America with a pale greenish body. Nymphs live in burro...
Yellow May Dun
Heptagenia sulphurea
A bright sulfur-yellow mayfly common across European rivers during early summer. Its flat nymphs are...