Animal Phylum Arthropoda (Arthropods)

These are probably 3rd instar larvae of Dicosmoecus gilvipes. The 4th instar larvae will be the round case made of sand grains.

In this picture: Caddisfly Species Dicosmoecus gilvipes (October Caddis).

The white blotches on this rock are Leucotrichia caddisfly cases, and the wispy tubes are cases made by a type of midge.

In this picture: Mayfly Species Ephemerella invaria (Sulphur Dun), Caddisfly Species Leucotrichia pictipes (Ring Horn Microcaddis), and True Fly Family Chironomidae (Midges).

Some large Ephemerella mayfly nymphs cling to a log. In the background, hundreds of Simuliidae black fly larvae swing in large clusters in the current.

In this picture: Mayfly Species Ephemerella subvaria (Hendrickson), True Fly Family Simuliidae (Black Flies), and Mayfly Species Ephemerella invaria (Sulphur Dun).

Three big Ephemerella subvaria mayfly nymphs share a rock with some cased caddis larvae.

In this picture: Mayfly Species Ephemerella subvaria (Hendrickson) and Saddle-case Maker Genus Glossosoma (Little Brown Short-horned Sedges).

This Ephemerella subvaria (Hendrickson) nymph picture is one of my favorites.

In this picture: Mayfly Species Ephemerella subvaria (Hendrickson).

There's a stonefly nymph in the bottom right corner of this picture, but what's really interesting is those white blotches. They're pretty common in my Wisconsin home river river, stuck flat onto the rocks--lots of rocks have a speckled look as a result. They are microcaddis cases, made by larvae of the caddisfly family Hydroptilidae. These are made by larvae of the subfamily Leucotrichiinae, most likely the genus Leucotrichia. They spin little flat oval cases of silk tight and immobile against the rocks.

In this picture: Caddisfly Species Leucotrichia pictipes (Ring Horn Microcaddis).

Cased caddis larvae blanket this section of stream bottom.

In this picture: Insect Order Trichoptera (Caddisflies).

Several caddis larvae cling in the current amongst the debris collected on an underwater alder branch.

In this picture: Insect Order Trichoptera (Caddisflies).