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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 121 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...120121122...126

Female Rhithrogena Mayfly Spinner

View 1 Pictures

Collected July 9, 2011 from the Touchet River in Washington
Added to Troutnut.com by Bnewell on July 10, 2011

Female Baetis (Blue-Winged Olives) Mayfly Spinner

View 1 Pictures

Collected July 13, 2011 from the Touchet River in Washington
Added to Troutnut.com by Bnewell on July 13, 2011

Male Isoperla fulva (Yellow Sally) Stonefly Adult

View 1 Pictures

Collected April 19, 2012 from the Touchet River in Washington
Added to Troutnut.com by Bnewell on April 19, 2012

Acari (Mites) Mite Adult

View 3 Pictures

Collected June 16, 2018 from the South Fork Snoqualmie River in Washington
Added to Troutnut.com by Troutnut on June 18, 2018

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

View 4 Pictures

Collected August 11, 2018 from the Henry's Fork of the Snake River in Idaho
Added to Troutnut.com by Troutnut on June 12, 2019

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

View 4 Pictures

Collected August 11, 2018 from the Henry's Fork of the Snake River in Idaho
Added to Troutnut.com by Troutnut on June 12, 2019

Epeorus longimanus (Slate Brown Dun) Mayfly Nymph

View 4 Pictures

Collected July 6, 2020 from Mystery Creek #249 in Washington
Added to Troutnut.com by Troutnut on July 12, 2020

Baetisca (Armored Mayflies) Mayfly Nymph

View 4 PicturesI'm unsure which species this is: it lacks the usual features of B. laurentina, but it's small, so maybe it's just an underdeveloped early instar (Instar: Many invertebrates molt through dozens of progressively larger and better-developed stages as they grow. Each of these stages is known as an instar. Hard-bodied nymphs typically molt through more instars than soft-bodied larvae.). Otherwise, it looks like it might be B. obesa.

Collected January 14, 2004 from unknown in Wisconsin
Added to Troutnut.com by Troutnut on January 25, 2006

Eurylophella (Chocolate Duns) Mayfly Nymph

View 2 PicturesIt has the segment 4 gill and abdominal segment 9 is longer than segment 8. I couldn't see abdominal 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.), but they may not yet be developed in such an early instar (Instar: Many invertebrates molt through dozens of progressively larger and better-developed stages as they grow. Each of these stages is known as an instar. Hard-bodied nymphs typically molt through more instars than soft-bodied larvae.).

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

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

View 3 PicturesThis is a really really really really tiny mayfly nymph. It has gills on abdominal segments 3-7 in the characteristic orientation for the Ephemerellidae family, and it has no fain tail as best I can tell, just uniform tail coverage with small black hairs of equal length. I think this one's too young to identify.

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

Specimen Page:1...120121122...126

Jargon Defined:

Instar: Many invertebrates molt through dozens of progressively larger and better-developed stages as they grow. Each of these stages is known as an instar. Hard-bodied nymphs typically molt through more instars than soft-bodied larvae.

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).

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.