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Mayfly Family Ephemerellidae (Hendricksons, Sulphurs, PMDs, BWOs)

Mayflies

Caddisflies

Stoneflies

Taxonomic Navigation -?-

Kingdom Animalia (Animals)

» Phylum Arthropoda (Arthropods)

» Class Insecta (Insects)

» Order Ephemeroptera (Mayflies)

» Family Ephemerellidae (Hendricksons, Sulphurs, PMDs, BWOs)

Genus in Ephemerellidae
Attenella	0	0
Caudatella	0	0
Dannella	0	0
DrunellaBlue-Winged Olives	0	0
EphemerellaHendricksons, Sulphurs, PMDs	0	37
EurylophellaChocolate Duns	0	0
Matriella	0	0
Penelomax	0	0
Serratella	0	0
TeloganopsisLittle black Quills	0	0
Timpanoga	0	0

3 genera aren't included.

Common Name

Match	Common Name
	Hendricksons, Sulphurs, PMDs, BWOs

Pictures Below ↓

This is page 5 of specimens of Ephemerellidae. Visit the main Ephemerellidae page for:

The behavior and habitat of Ephemerellidae.
37 underwater pictures of Ephemerellidae.

Pictures of 271 Mayfly Specimens in the Family Ephemerellidae:

Specimen Page:1...456...28

Female Drunella grandis (Western Green Drake) Mayfly Dun

View 6 PicturesI collected this specimen while away from all my good photography equipment except the camera and one of my macro lenses, so I made do. The lighting is from lamps in a hotel room, so it was hard to edit for really true colors, but I tried to get as close as possible. The body was 13 mm long, wing 19 mm long.

Collected July 14, 2017 from the American River in Washington
Added to Troutnut.com by Troutnut on July 24, 2017

Female Ephemerella invaria (Sulphur Dun) Mayfly Spinner

View 5 Pictures

Collected May 26, 2007 from Penn's Creek in Pennsylvania
Added to Troutnut.com by Troutnut on June 4, 2007

Female Attenella attenuata (Small Eastern Blue-Winged Olive) Mayfly Dun

View 4 PicturesThis specimen came from the same hatch as a male.

Collected June 8, 2005 from the Namekagon River in Wisconsin
Added to Troutnut.com by Troutnut on May 26, 2006

Female Ephemerella invaria (Sulphur Dun) Mayfly Dun

View 5 Pictures

Collected May 25, 2007 from the Little Juniata River in Pennsylvania
Added to Troutnut.com by Troutnut on June 4, 2007

Male Eurylophella (Chocolate Duns) Mayfly Dun

View 5 Pictures

Collected June 14, 2005 from the Teal River in Wisconsin
Added to Troutnut.com by Troutnut on May 26, 2006

Ephemerella needhami (Little Dark Hendrickson) Mayfly Nymph

View 5 PicturesI took quite a few notes at the microscope when I collected this specimen. They're attached to the appropriate pictures.

I found this specimen in the same collection as a similar one. Since I only have strange views of this one, it's possible that they're actually the same specimen and I somehow confused my picture-ordering and got the impression that they're different nymphs.

Collected June 8, 2005 from the Namekagon River in Wisconsin
Added to Troutnut.com by Troutnut on May 26, 2006

Ephemerella needhami (Little Dark Hendrickson) Mayfly Nymph

View 5 PicturesThis specimen strikingly resembles another specimen from about 1300 miles away in the Catskills, which I tentatively called Ephemerella aurivillii. This one has much more prominent abdominal tubercles (

A few (not all) of the abdominal tubercles on this Ephemerella needhami nymph are circled. They are especially large in this species.

Tubercle: Various peculiar little bumps or projections on an insect. Their character is important for the identification of many kinds of insects, such as the nymphs of Ephemerellidae mayflies.). It may be that they're both the same species and I don't have my identifications straight.

Collected June 5, 2005 from the Long Lake Branch of the White River in Wisconsin
Added to Troutnut.com by Troutnut on May 24, 2006

Female Ephemerellidae (Hendricksons, Sulphurs, PMDs, BWOs) Mayfly Spinner

View 7 PicturesThis Ephemerellidae spinner was emerging unusually late, and on a warm stream. Since it's a female, identification is difficult. Her identical coloration suggests she's probably of the same species as this specimen collected on a cool trout stream almost a month earlier.

Collected July 28, 2005 from the West Fork of the Chippewa River in Wisconsin
Added to Troutnut.com by Troutnut on April 14, 2006

Male Eurylophella (Chocolate Duns) Mayfly Spinner

View 12 Pictures

Collected June 3, 2005 from the Namekagon River in Wisconsin
Added to Troutnut.com by Troutnut on May 24, 2006

Male Ephemerella excrucians (Pale Morning Dun) Mayfly Dun

View 7 Pictures

Collected July 31, 2020 from the Henry's Fork of the Snake River in Idaho
Added to Troutnut.com by Troutnut on August 17, 2020

Specimen Page:1...456...28

Jargon Defined:

Nymphs: The juvenile, underwater stages of mayflies, stoneflies, dragonflies, and damselflies and other aquatic insects whose juvenile stages are covered by hard exoskeletons. The word can also refer to the fishing flies which imitate these creatures, in which case it is used as a blanket term for flies imitating any underwater stage of an invertebrate (except for crayfish and leeches).

Spinner: There are two winged stages of adult mayflies. They emerge from the water as duns, molt on land (usually) into their fully mature stage, spinners. As spinners, they mate, lay eggs, and die.

A few (not all) of the abdominal tubercles on this Ephemerella needhami nymph are circled. They are especially large in this species.

Tubercles: Various peculiar little bumps or projections on an insect. Their character is important for the identification of many kinds of insects, such as the nymphs of Ephemerellidae mayflies.

Useful References:

Arbona, Fred Jr. 1989. Mayflies, the Angler, and the Trout. Nick Lyons Books.

Caucci, Al and Nastasi, Bob. 2004. Hatches II. The Lyons Press.

Leonard, Justin W. and Fannie A. Leonard. 1962. Mayflies of Michigan Trout Streams. Cranbrook Institute of Science.