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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 11 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...101112...28

Eurylophella (Chocolate Duns) Mayfly Nymph

View 3 PicturesLooking at this specimen under a microscope revealed prominent sharp 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.). Also, abdominal segment 9 is distinctly longer than abdominal segment 8, meaning this is definitely a Eurylophella nymph.

Collected February 7, 2004 from unknown in Wisconsin
Added to Troutnut.com by Troutnut on January 25, 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

Ephemerella subvaria (Hendrickson) Mayfly Nymph

View 3 Pictures

Collected March 10, 2004 from unknown in Wisconsin
Added to Troutnut.com by Troutnut on January 25, 2006

Female Eurylophella (Chocolate Duns) Mayfly Spinner

View 4 PicturesI collected this uncooperative specimen as part of a small cloud of female spinners clustered tightly together high about 10 feet above the water, without any males that I could see.

Collected June 21, 2005 from the Namekagon River in Wisconsin
Added to Troutnut.com by Troutnut on May 26, 2006

Male Ephemerella subvaria (Hendrickson) Mayfly Dun

View 3 Pictures

Collected April 14, 2004 from the Namekagon River in Wisconsin
Added to Troutnut.com by Troutnut on January 25, 2006

Male Ephemerella subvaria (Hendrickson) Mayfly Dun

View 3 Pictures

Collected April 24, 2004 from the Namekagon River in Wisconsin
Added to Troutnut.com by Troutnut on January 25, 2006

Female Ephemerella subvaria (Hendrickson) Mayfly Dun

View 3 Pictures

Collected April 24, 2004 from the Namekagon River in Wisconsin
Added to Troutnut.com by Troutnut on January 25, 2006

Female Ephemerella subvaria (Hendrickson) Mayfly Dun

View 3 Pictures

Collected May 1, 2004 from the Namekagon River in Wisconsin
Added to Troutnut.com by Troutnut on January 25, 2006

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

View 3 PicturesThis specimen came from the same hatch as a female.

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

Ephemerella subvaria (Hendrickson) Mayfly Nymph

View 3 Pictures

Collected January 12, 2004 from unknown in Wisconsin
Added to Troutnut.com by Troutnut on January 25, 2006

Specimen Page:1...101112...28

Jargon Defined:

Nymph: 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).

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.