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Arthropod Class Insecta (Insects)

Mayflies

Caddisflies

Stoneflies

Taxonomic Navigation -?-

Kingdom Animalia (Animals)

» Phylum Arthropoda (Arthropods)

» Class Insecta (Insects)

Order in Insecta
ColeopteraBeetles	0	1
DipteraTrue Flies	0	9
EphemeropteraMayflies	0	67
HemipteraTrue Bugs	0	7
HymenopteraAnts, Bees, and Wasps	0	0
LepidopteraMoths	0	0
MegalopteraHellgrammites, Dobsonflies, and Alderflies	0	0
Odonata-AnisopteraDragonflies	0	0
Odonata-ZygopteraDamselflies	0	0
OrthopteraGrasshoppers and Crickets	0	0
PlecopteraStoneflies	0	6
Psocodea	0	0
TrichopteraCaddisflies	0	55

1 order isn't included.

Common Name

Match	Common Name
	Insects

Pictures Below ↓

Nearly a million species of insects have been described by entomologists. I have left several of them off of this site, just to save time, but I've tried to include all the main aquatic insects trout eat in North America.

This site focuses on aquatic insects, of which the most important are mayflies (Ephemeroptera) and caddisflies (Trichoptera). Stoneflies (Plecoptera) come in third, a position arguably challenged by the many two-winged true flies of the Diptera order, which includes midges and craneflies. I've also included some terrestrial (Terrestrial: Insects which live on land and are fed on by trout only when they incidentally fall into the water are known as "terrestrials" to fly anglers, and they're very important in late summer.) insects which I've found on or near trout streams. Terrestrials (Terrestrial: Insects which live on land and are fed on by trout only when they incidentally fall into the water are known as "terrestrials" to fly anglers, and they're very important in late summer.) like ants, beetles, and grasshoppers are an important food source for trout in many places, especially during the summer months.

Aquatic insects do not live their entire lives in the water. Instead, they grow for a year (give or take quite a bit) as nymphs or larvae underwater, and then they emerge into air-breathing winged insects for a short while to mate and die. There are many variations on this theme.

The most important aquatic insects for fly fishermen are mayflies, stoneflies, caddisflies, and midges. Mayflies and caddisflies are the most discussed by angler-entomologists, because it's so useful to closely identify them. The behavior of their species guides the behavior of feeding trout, and an angler who understands the lifecycle of a particular species has the upper hand when it's hatching. This is not so important for stoneflies and midges, because their hatching behavior is less variable.

Pictures of 1229 Insect Specimens:

Specimen Page:12 3 4...124

Baetisca obesa (Armored Mayfly) Mayfly Nymph

View 12 Pictures

Collected May 6, 2007 from the Neversink River (above reservoir) in New York
Added to Troutnut.com by Troutnut on May 10, 2007

Corydalus (Dobsonflies) Hellgrammite Larva

View 27 Pictures

Collected May 29, 2007 from Paradise Creek in Pennsylvania
Added to Troutnut.com by Troutnut on June 4, 2007

Rhyacophila fuscula (Green Sedge) Caddisfly Larva

View 11 Pictures

Collected April 1, 2007 from Mystery Creek #62 in New York
Added to Troutnut.com by Troutnut on April 3, 2007

Specimen Page:12 3 4...124

114 Underwater Pictures of Insects:

Underwater Photo Page:12 3 4...13

View Full Size and Comment (2.5X larger)

Hundreds of cased caddisfly larvae live on this log in a small brook trout stream.

In this picture: Insect Order Trichoptera (Caddisflies).

StateWisconsin

LocationEighteenmile Creek

Date TakenApr 14, 2004

Date AddedJan 25, 2006

AuthorTroutnut

CameraOlympus C740UZ

View Full Size and Comment (1.7X larger)

Several Baetidae nymphs line up on a rock.

In this picture: Mayfly Family Baetidae (Blue-Winged Olives).

StateNew York

LocationMongaup Creek

Date TakenApr 19, 2006

Date AddedApr 22, 2006

AuthorTroutnut

CameraPENTAX Optio WPi

View Full Size and Comment (2.2X larger)

Desktop Backgrounds

This is my favorite underwater picture so far. It shows a bunch of Simuliidae (black fly) larvae clinging to a rock and swinging in the fast current. There are also at least four visible mayfly nymphs, probably in the family Baetidae.

In this picture: True Fly Family Simuliidae (Black Flies) and Mayfly Family Baetidae (Blue-Winged Olives).

StateWisconsin

LocationEighteenmile Creek

Date TakenMar 19, 2004

Date AddedJan 25, 2006

AuthorTroutnut

CameraOlympus C740UZ

Underwater Photo Page:12 3 4...13

Recent Discussions of Insecta

Missing genera (from missing list)

Posted by AndyV on Nov 8, 2022 in the family Caenidae

Latineosus, Sparbarus, Susperatus should all be included in the genera that aren't included (I think).

Andy

Reply Correct hatch time of year Hydropsyche slossonae? 10 Replies »

Posted by AndyV on Aug 26, 2022 in the species Hydropsyche slossonae

Last reply on Oct 11, 2022 by AndyV

I've seen hatch charts (e.g. DNR hatch chart for SE MN) stating mid-May til the end of July vs June (from this site). Can anyone confirm?

Reply acentrella nymph 22 Replies »

Posted by Goose on Nov 3, 2006 in the genus Acentrella

Last reply on Sep 15, 2022 by Wiflyfisher

Hi Jason! Do you have a picture of the (acentrella-miniature BWO nymph) on the site? I've been fishing them and wanted a better idea of how they look.
Thanks,
Bruce

Reply Family name now Thremmatidae (Little Northeastern Casemakers)

Posted by AndyV on Aug 25, 2022 in the family Uenoidae

I believe Uenoidae is now known as Thremmatidae.

~Andy

Reply Plectrocnemia missing

Posted by AndyV on Aug 25, 2022 in the family Polycentropodidae

I believe this is missing from the list. Unsure of it's importance. However, they was a study on Plectrocnemia conspersa relative to trout populations in Ashdown Forest streams [Schofield et al. (1988)].

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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.

Nymphs: 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).

Terrestrial: Insects which live on land and are fed on by trout only when they incidentally fall into the water are known as "terrestrials" to fly anglers, and they're very important in late summer.