Blog & Latest Updates
Fly Fishing Articles
Insects by Common Name

Trout Streams & Rivers
Trout Pictures
Underwater Pictures

Desktop Backgrounds
Stream & Bug Videos
Image Use Pricing

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 109 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...108109110...125

Female Baetis tricaudatus (Blue-Winged Olive) Mayfly Dun

View 6 PicturesThis one emerged from a nymph of this kind in my studio but got a bit waterlogged before I could pull it out to photograph.

Collected September 12, 2020 from the Yakima River in Washington
Added to Troutnut.com by Troutnut on September 19, 2020

Female Baetidae (Blue-Winged Olives) Mayfly Dun

View 3 Pictures

Collected May 22, 2004 from unknown in Wisconsin
Added to Troutnut.com by Troutnut on January 25, 2006

Baetidae (Blue-Winged Olives) Mayfly Nymph

View 3 PicturesHere's a Baetid nymph close to hatching, with darkened wingpads. It's got dark bands on the tail at the middle and tip, a rounded, oval 7th gill, and gill veinlets (Veinlet: Short insect wing veins connecting the major longitudinal veins to the wing margin.) which are visible but not conspicuous.

Collected August 8, 2004 from unknown in Wisconsin
Added to Troutnut.com by Troutnut on January 25, 2006

Ephemerella (Hendricksons, Sulphurs, PMDs) Mayfly Nymph

View 2 PicturesHere's a puzzling nymph. It seemed to have double-banded tibiae (

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

Tibia: A middle segments in the leg of an insect, located between the femur and the tarsus.), although the second band wasn't very pronounced. It has quite prominent 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.) that definitely aren't black.

Collected March 10, 2004 from unknown in Wisconsin
Added to Troutnut.com by Troutnut on January 19, 2006

Female Leucrocuta hebe (Little Yellow Quill) Mayfly Dun

View 4 PicturesI found Catskill brown trout eagerly surface feeding to this species.

Collected August 22, 2004 from the Beaverkill River in New York
Added to Troutnut.com by Troutnut on January 25, 2006

Siphlonurus quebecensis (Gray Drake) Mayfly Nymph

View 2 Pictures

Collected June 1, 2005 from the Bois Brule River in Wisconsin
Added to Troutnut.com by Troutnut on May 24, 2006

Ephemerellidae (Hendricksons, Sulphurs, PMDs, BWOs) Mayfly Nymph

View 2 Pictures

Collected June 1, 2005 from the Bois Brule River in Wisconsin
Added to Troutnut.com by Troutnut on May 24, 2006

Isoperla fulva (Yellow Sally) Stonefly Adult

View 4 PicturesAn adult stonefly carrying a load of red mites.

Collected May 31, 2011 from the Touchet River in Washington
Added to Troutnut.com by Bnewell on June 27, 2011

Chironomidae (Midges) Midge Larva

View 8 PicturesThese larvae were all over the submerged rocks in a small mountain stream in the Washington Cascades, tightly adhering to the rocks in their flat, half-disk-shaped cases.

Collected July 25, 2019 from Mystery Creek #249 in Washington
Added to Troutnut.com by Troutnut on July 27, 2019

Helicopsyche borealis (Speckled Peter) Caddisfly Adult

View 7 PicturesThis one keys pretty easily to the Helicopsychidae family, of which there is only one genus in North America, and one species reported in this general area.

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

Specimen Page:1...108109110...125

Jargon Defined:

Larvae: Many classes of aquatic insects, such as caddisflies, midges, craneflies, dobsonflies, alderflies, and many more, are known as "larvae" rather than "nymphs" in their juvenile stages. They have mostly soft bodies rather than hard exoskeletons. These insects also advance through a "pupa" stage before reaching adulthood.

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).

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

Tibiae: A middle segments in the leg of an insect, located between the femur and the tarsus.

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.

Veinlets: Short insect wing veins connecting the major longitudinal veins to the wing margin.