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Mayfly Genus Ephemerella (Hendricksons, Sulphurs, PMDs)

Taxonomic Navigation -?-
» Genus Ephemerella (Hendricksons, Sulphurs, PMDs)
Species in EphemerellaNumber of SpecimensNumber of Pictures
Ephemerella aurivillii00
Ephemerella dorothea dorotheaPale Evening Dun00
Ephemerella dorothea infrequensPale Morning Dun00
Ephemerella excruciansPale Morning Dun00
Ephemerella invariaSulphur Dun015
Ephemerella needhamiLittle Dark Hendrickson00
Ephemerella subvariaHendrickson024
Ephemerella tibialisLittle Western Dark Hendrickson00

11 species aren't included.
Common Name
MatchCommon Name
****Hendricksons, Sulphurs, PMDs


Pictures Below ↓

This is page 15 of specimens of Ephemerella. Visit the main Ephemerella page for:

  • The behavior and habitat of Ephemerella.
  • 37 underwater pictures of Ephemerella.

Pictures of 158 Mayfly Specimens in the Genus Ephemerella:

Specimen Page:1...14151617
Ephemerella aurivillii Mayfly NymphEphemerella aurivillii Mayfly Nymph View 5 PicturesThis nymph hatched out in my aquarium into this dun.
Collected July 10, 2011 from Nome Creek in Alaska
Added to Troutnut.com by Troutnut on July 13, 2011
Female Ephemerella excrucians (Pale Morning Dun) Mayfly DunFemale Ephemerella excrucians (Pale Morning Dun) Mayfly Dun View 5 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
Male Ephemerella excrucians (Pale Morning Dun) Mayfly NymphMale Ephemerella excrucians (Pale Morning Dun) Mayfly Nymph View 11 PicturesI used the ID of this nymph (and some others like it) to infer the identity of a female dun collected on the same trip.
Collected July 4, 2020 from Mystery Creek #249 in Washington
Added to Troutnut.com by Troutnut on July 12, 2020
Female Ephemerella excrucians (Pale Morning Dun) Mayfly SpinnerFemale Ephemerella excrucians (Pale Morning Dun) Mayfly Spinner View 6 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
Female Ephemerella invaria (Sulphur Dun) Mayfly SpinnerFemale Ephemerella invaria (Sulphur Dun) Mayfly Spinner View 4 PicturesHere's the first sulphur dun I found in the 2004 season.
Collected May 18, 2004 from the Namekagon River in Wisconsin
Added to Troutnut.com by Troutnut on January 25, 2006
Ephemerella (Hendricksons, Sulphurs, PMDs) Mayfly NymphEphemerella (Hendricksons, Sulphurs, PMDs) Mayfly Nymph View 4 Pictures
Collected June 1, 2005 from the Bois Brule River in Wisconsin
Added to Troutnut.com by Troutnut on May 24, 2006
Male Ephemerella invaria (Sulphur Dun) Mayfly DunMale Ephemerella invaria (Sulphur Dun) Mayfly Dun View 3 Pictures
Collected May 29, 2004 from unknown in Wisconsin
Added to Troutnut.com by Troutnut on January 25, 2006
Female Ephemerella excrucians (Pale Morning Dun) Mayfly DunFemale Ephemerella excrucians (Pale Morning Dun) Mayfly Dun View 12 PicturesThis "specimen" is actually two different duns, one missing the middle front and back left legs, the other missing the terminal filament i.e. middle tail. I added them together by accident, but since they're the same species, stage, and gender, I might as well leave them together.
Collected August 2, 2020 from the Big Lost River in Idaho
Added to Troutnut.com by Troutnut on August 18, 2020
Male Ephemerella (Hendricksons, Sulphurs, PMDs) Mayfly SpinnerMale Ephemerella (Hendricksons, Sulphurs, PMDs) Mayfly Spinner View 3 Pictures
Collected May 26, 2007 from Penn's Creek in Pennsylvania
Added to Troutnut.com by Troutnut on June 4, 2007
Ephemerella aurivillii Mayfly NymphEphemerella aurivillii Mayfly Nymph View 11 PicturesThis is a puzzling one to identify and I'm not sure about the species. The maxillary palp (
The palp on the maxilla of an Ephemerella nymph (detached and photographed under a microscope) is highlighted in red here.
The palp on the maxilla of an Ephemerella nymph (detached and photographed under a microscope) is highlighted in red here.
Palp: A long, thin, often segmented appendage which can protrude from certain insect mouth parts such as the maxillae. Also known as the < />palpus.) is present and segmented, and the maxillary canines are not strongly serrate laterally. I think it's Ephemerella, not Serratella. The ventral (Ventral: Toward or on the bottom.) lamellae of the gills on abdominal segment 6 have a clear median notch with a depth at least half the length of the lamellae, which points toward a couple of uncommon species (most likely Ephemerella alleni), but the abdominal tubercles (
A few (not all) of the abdominal tubercles on this Ephemerella needhami nymph are circled. They are especially large in this species.
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.) and coloration don't fit that species. To add to the confusion, none of the above species are expected to emerge in the fall, as far as I know. I'm going to call this one Ephemerella aurivillii for now, but that's highly uncertain.
Collected September 10, 2020 from the Foss River in Washington
Added to Troutnut.com by Troutnut on September 19, 2020
Specimen Page:1...14151617
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