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**Mayfly Genus Eurylophella (Chocolate Duns)**

Mayflies

Caddisflies

Stoneflies

Taxonomic Navigation -?-

Kingdom Animalia (Animals)

» Phylum Arthropoda (Arthropods)

» Class Insecta (Insects)

» Order Ephemeroptera (Mayflies)

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

» Genus Eurylophella (Chocolate Duns)

Species in Eurylophella
Eurylophella bicolorChocolate Dun	0	0
Eurylophella funeralisChocolate Dun	0	0
Eurylophella lutulentaChocolate Dun	0	0
Eurylophella temporalisChocolate Dun	1	9

10 species aren't included.

Common Name

Match	Common Name
	Chocolate Duns

Pictures Below ↓

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

The behavior and habitat of Eurylophella.

Pictures of 22 Mayfly Specimens in the Genus Eurylophella:

Specimen Page:123

Male Eurylophella (Chocolate Duns) Mayfly Spinner

View 12 Pictures

Collected June 3, 2005 from the Namekagon River in Wisconsin
Added to Troutnut.com by Troutnut on May 24, 2006

Female Eurylophella (Chocolate Duns) Mayfly Spinner

View 4 PicturesI collected this uncooperative specimen as part of a small cloud of female spinners clustered tightly together high about 10 feet above the water, without any males that I could see.

Collected June 21, 2005 from the Namekagon River in Wisconsin
Added to Troutnut.com by Troutnut on May 26, 2006

Eurylophella (Chocolate Duns) Mayfly Nymph

View 5 Pictures

Collected January 31, 2004 from unknown in Wisconsin
Added to Troutnut.com by Troutnut on January 25, 2006

Eurylophella (Chocolate Duns) Mayfly Nymph

View 5 PicturesThis nymph is an extremely 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 February 7, 2004 from unknown in Wisconsin
Added to Troutnut.com by Troutnut on January 25, 2006

Eurylophella (Chocolate Duns) Mayfly Nymph

View 4 PicturesClose examination under a microscope easily showed 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.).

Collected January 31, 2004 from unknown in Wisconsin
Added to Troutnut.com by Troutnut on January 25, 2006

Eurylophella (Chocolate Duns) Mayfly Nymph

View 3 Pictures

Collected February 5, 2004 from unknown in Wisconsin
Added to Troutnut.com by Troutnut on January 25, 2006

Eurylophella (Chocolate Duns) Mayfly Nymph

View 3 PicturesThis nymph is an extremely 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 February 7, 2004 from unknown in Wisconsin
Added to Troutnut.com by Troutnut on January 25, 2006

Eurylophella (Chocolate Duns) Mayfly Nymph

View 3 PicturesLooking at this specimen under a microscope revealed prominent sharp 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.). Also, abdominal segment 9 is distinctly longer than abdominal segment 8, meaning this is definitely a Eurylophella nymph.

Collected February 7, 2004 from unknown in Wisconsin
Added to Troutnut.com by Troutnut on January 25, 2006

Eurylophella (Chocolate Duns) Mayfly Nymph

View 3 Pictures

Collected February 7, 2004 from unknown in Wisconsin
Added to Troutnut.com by Troutnut on January 25, 2006

Eurylophella (Chocolate Duns) Mayfly Nymph

Collected February 7, 2004 from unknown in Wisconsin
Added to Troutnut.com by Troutnut on January 25, 2006

Specimen Page:123

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.

Useful References:

Caucci, Al and Nastasi, Bob. 2004. Hatches II. The Lyons Press.

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