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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 103 of specimens of Arthropoda. Visit the main Arthropoda page for:

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

Pictures of 1244 Arthropod Specimens:

Specimen Page:1...102103104...126

Corydalidae (Hellgrammites) Hellgrammite Larva

Corydalidae (Hellgrammites) Insect Larva

View 3 Pictures

Collected March 9, 2004 from unknown in Wisconsin
Added to Troutnut.com by Troutnut on January 25, 2006

Cinygmula (Dark Red Quills) Mayfly Nymph

View 9 Pictures

Collected July 17, 2011 from the Gulkana River in Alaska
Added to Troutnut.com by Troutnut on July 20, 2011

Female Paraleptophlebia (Blue Quills and Mahogany Duns) Mayfly Dun

View 5 PicturesI hadn't seen an intact adult mayfly to catch all day, when suddenly I saw this Paraleptophlebia dun flying six inches in front of my face and nabbed it with my hand without even thinking. It has some sort of bright debris on it that probably comes from placing it in a transport container that hadn't been cleaned recently enough.

Collected July 28, 2019 from Mystery Creek #250 in Washington
Added to Troutnut.com by Troutnut on July 29, 2019

Isonychia bicolor (Mahogany Dun) Mayfly Nymph

View 3 Pictures

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 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

Female Rhithrogena hageni (Western Black Quill) Mayfly Dun

View 7 PicturesI was surprised by the olive cast on the body of this female Rhithrogena dun, which led me to mistake it for a western green drake (Drunella) in the field. I was pleasantly surprised to get a closer look and find something I hadn't collected yet. Its species ID is based on proximity to male spinner collected on the same trip, as well as physical similarity (size, tergite (

One tergite of this Isonychia bicolor mayfly spinner is highlighted in red.

Tergite: The top (dorsal) part of a single segment on an insect's abdomen when it consists of a single chitinous plate (sclerite), or an individual sclerite if the segment has more than one.) coloration, dark streaks on the 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.)) to that specimen.

Collected July 4, 2020 from Mystery Creek #249 in Washington
Added to Troutnut.com by Troutnut on July 12, 2020

Male Ephemerellidae (Hendricksons, Sulphurs, PMDs, BWOs) Mayfly Dun

View 11 Pictures

Collected June 16, 2018 from the South Fork Snoqualmie River in Washington
Added to Troutnut.com by Troutnut on June 21, 2018

Baetisca laurentina (Armored Mayfly) Mayfly Nymph

View 3 Pictures

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

Epeorus (Little Maryatts) Mayfly Nymph

View 3 Pictures

Collected April 24, 2007 from Factory Brook in New York
Added to Troutnut.com by Troutnut on April 24, 2007

Male Hydropsyche (Spotted Sedges) Caddisfly Adult

View 8 Pictures

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...102103104...126

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.

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.

One tergite of this Isonychia bicolor mayfly spinner is highlighted in red.

Tergite: The top (dorsal) part of a single segment on an insect's abdomen when it consists of a single chitinous plate (sclerite), or an individual sclerite if the segment has more than one.