Mayfly Genus Attenella

Mayflies

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Stoneflies

Taxonomic Navigation -?-

Kingdom Animalia (Animals)

» Phylum Arthropoda (Arthropods)

» Class Insecta (Insects)

» Order Ephemeroptera (Mayflies)

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

» Genus Attenella

Species in Attenella
Attenella attenuataSmall Eastern Blue-Winged Olive	0	0
Attenella delantalaSmall Blue-Winged Olive	0	0
Attenella margaritaLittle Western Blue-Winged Olive	0	0

1 species isn't included.

Pictures Below ↓

This is page 2 of specimens of Attenella. Visit the main Attenella page for:

The behavior and habitat of Attenella.

Pictures of 7 Mayfly Specimens in the Genus Attenella:

Specimen Page:12

Male Attenella delantala (Small Blue-Winged Olive) Mayfly Nymph

View 10 Pictures

Collected July 25, 2019 from Mystery Creek #249 in Washington
Added to Troutnut.com by Troutnut on July 26, 2019

Female Attenella delantala (Small Blue-Winged Olive) Mayfly Nymph

View 5 Pictures

Collected July 25, 2019 from Mystery Creek #249 in Washington
Added to Troutnut.com by Troutnut on July 26, 2019

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

View 4 PicturesThis dun was badly damaged in transport and all its legs fell off, but I photographed it anyway because I wasn't sure I would fine more and it's an interesting species. Luckily I collected better specimens a few days later.

Collected June 5, 2005 from the Namekagon River in Wisconsin
Added to Troutnut.com by Troutnut on May 25, 2006

Attenella margarita (Little Western Blue-Winged Olive) Mayfly Nymph

View 7 PicturesNotes from the microscope on the ID: Maxillary palp (

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, distinctly 2-segmented, but very small. Gills on segment 4-7. This specimen has some unfortunate damage to the abdomen, but it's the only one I found in my sample.

Collected August 3, 2020 from the East Fork Big Lost River in Idaho
Added to Troutnut.com by Troutnut on August 19, 2020

Specimen Page:12

Jargon Defined:

Abdomen: The rear and usually the longest (ten-segmented in mayflies) portion of an insect's body, to which the tails are attached.

Dun: Mayflies have two adult stages. They first emerge from the water as duns (scientifically known as the subimago stage). They then molt into the spinner (imago) stage, in which they mate and die. Sometimes the word "dun" is confusingly used to refer to a brownish gray color in fly tying materials.

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.

Useful References:

Knopp, Malcolm and Robert Cormier. 1997. Mayflies: An Angler's Study of Trout Water Ephemeroptera . The Lyons Press.