Animal Phylum Arthropoda (Arthropods)

There are several mayfly and stonefly nymphs clinging to this log.

In this picture: Mayfly Family Baetidae (Blue-Winged Olives) and Stonefly Family Taeniopterygidae (Willowflies).

This Brachycentrus "Apple Caddis" struggled more than its kin in escaping its pupal skin, enabling me to take an underwater picture of it from directly below. This is sort of a trout's eye view, but I used the flash for the picture so the transparent shuck (

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Here's an underwater view of the pupal shucks of several already-emerged Brachycentrus numerosus caddisflies.

Shuck: The shed exoskeleton left over when an insect molts into its next stage or instar. Most often it describes the last nymphal or pupal skin exited during emergence into a winged adult.) appears far brighter than it really is.

In this picture: Caddisfly Species Brachycentrus appalachia (Apple Caddis).

There's a large Ephemerella subvaria nymph in the top left.

In this picture: Mayfly Species Ephemerella invaria (Sulphur Dun), Insect Order Trichoptera (Caddisflies), and Mayfly Species Ephemerella subvaria (Hendrickson).

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).

Cased caddis larvae blanket this section of stream bottom.

In this picture: Insect Order Trichoptera (Caddisflies).

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).

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

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