Arthropod Class Insecta (Insects)

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).

Cased caddis larvae blanket this section of stream bottom.

In this picture: Insect Order Trichoptera (Caddisflies).

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).

Hundreds of cased caddis larvae cling to sparse weed growth in the sand under heavy current.

In this picture: Insect Order Trichoptera (Caddisflies).

A variety of cased caddisfly larvae, probably mostly Neophylax, have clustered along the backside of a rock in fast water. There seem to be some Helicopsychidae larvae clustered along the bottom, and a few other taxa are mixed in. It's interesting that several larvae have especially large stones placed over the front openings of their cases, perhaps to block the case off for pupation.

It does seem to be the wrong time of year for Neophylax to be pupating, but that was the ID given for one of these which I collected and photographed up close.

In this picture: Caddisfly Genus Neophylax (Autumn Mottled Sedges) and Caddisfly Genus Helicopsyche (Speckled Peters).

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

In this picture: Insect Order Trichoptera (Caddisflies).