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Animal Phylum Arthropoda (Arthropods)

Mayflies

Caddisflies

Stoneflies

Taxonomic Navigation -?-

Kingdom Animalia (Animals)

» Phylum Arthropoda (Arthropods)

Class in Arthropoda
ArachnidaMites and Spiders	0	1
CollembolaSpringtails	0	0
Crustacea-MalacostracaCrayfish, Scuds, and Sowbugs	0	10
Crustacea-Maxillopoda	0	0
InsectaInsects	0	114

Common Name

Match	Common Name
	Arthropods

Pictures Below ↓

This is page 116 of specimens of Arthropoda. Visit the main Arthropoda page for:

The behavior and habitat of Arthropoda.
122 underwater pictures of Arthropoda.

Pictures of 1243 Arthropod Specimens:

Specimen Page:1...115116117...125

Leptoceridae Caddisfly Adult

View 7 Pictures

Collected June 30, 2019 from the Madison River in Montana
Added to Troutnut.com by Troutnut on July 17, 2019

Female Acerpenna pygmaea (Tiny Blue-Winged Olive) Mayfly Spinner

View 3 Pictures

Collected August 1, 2020 from the Henry's Fork of the Snake River in Idaho
Added to Troutnut.com by Troutnut on August 18, 2020

Epeorus deceptivus Mayfly Nymph

View 4 PicturesIdentification notes from the microscope: Gills on segment 1 extend anteriorly below the body, but not all the way to touching; posterolateral spines minor; femora (

The femur of this Isonychia bicolor mayfly spinner is highlighted in red.

Femur: The main segment of an insect's leg close to the body, in between the tibia and the trochanter.) without fuscous macula.

Collected August 4, 2020 from Green Lake Outlet in Idaho
Added to Troutnut.com by Troutnut on August 20, 2020

Female Siphlonurus occidentalis (Gray Drake) Mayfly Dun

View 6 PicturesI caught this specimen two days' walk from my macro lenses, but I don't think I have a dun of this species yet, so I took the best photos I could with my iPhone.

Collected August 30, 2020 from Island Lake in Wyoming
Added to Troutnut.com by Troutnut on September 18, 2020

Female Baetis tricaudatus (Blue-Winged Olive) Mayfly Spinner

View 5 PicturesThis female spinner was deceased when photographed, so the posture is unnatural, but it was a substantial hatch and clearly worth imitating (with wet flies to imitate the sunken ovipositing females) so I went ahead with the photos.

It was collected in association with a male spinner.

Collected September 4, 2020 from Silver Creek in Idaho
Added to Troutnut.com by Troutnut on September 18, 2020

Rhithrogena Mayfly Dun

View 1 Pictures

Collected March 27, 2010 from the Big Thompson River in Montana
Added to Troutnut.com by Bnewell on June 26, 2011

Drunella grandis (Western Green Drake) Mayfly Nymph

View 2 Pictures

Collected June 16, 2005 from the Vermillion River in Montana
Added to Troutnut.com by Bnewell on June 27, 2011

Female Baetis (Blue-Winged Olives) Mayfly Dun

View 2 Pictures

Collected June 30, 2011 from the Touchet River in Washington
Added to Troutnut.com by Bnewell on June 30, 2011

Male Cinygmula mimus Mayfly Adult

View 1 Pictures

Collected May 20, 2012 from the Touchet River in Washington
Added to Troutnut.com by Bnewell on May 25, 2012

Female Drunella flavilinea (Flav) Mayfly Dun

View 6 PicturesI can't be certain of the ID of this female dun, but I'm calling it Drunella flavilinea for three reasons: 1) the known abundance of "flavs" on the Henry's Fork, 2) clear differences in coloration from my confirmed specimens of Drunella coloradensis, which is the main lookalike, and 3) the habitat (a sizable river in a wide mountain valley, rather than a small, high-altitude stream) suggests it's not coloradensis.

Collected July 31, 2020 from the Henry's Fork of the Snake River in Idaho
Added to Troutnut.com by Troutnut on August 16, 2020

Specimen Page:1...115116117...125

Jargon Defined:

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 femur of this Isonychia bicolor mayfly spinner is highlighted in red.

Femora: The main segment of an insect's leg close to the body, in between the tibia and the trochanter.

Ovipositing: To lay eggs.

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.