Insect Order Trichoptera (Caddisflies)

Despite the late date in the season, several caddisfly larvae remain on the rocks in this river.

In this picture: Insect Order Trichoptera (Caddisflies).

This picture from below shows a stillborn (

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This stillborn Ephemerella subvaria dun is trapped in its shuck.

Stillborn: In fly fishing, a stillborn insect is one which got stuck in its nymphal or pupal shuck during emergence and floats helplessly on the surface instead of flying away. It is a specific class of cripple, although it is sometimes used interchangeably with that term.) Ephemerella subvaria (Hendrickson) dun drifting on the surface amidst a number of shed pupal skins from Brachycentrus caddisflies which were heavily hatching that day.

In this picture: Mayfly Species Ephemerella subvaria (Hendrickson) and Caddisfly Species Brachycentrus appalachia (Apple Caddis).

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).

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

In this picture: Saddle-case Maker Genus Glossosoma (Little Brown Short-horned Sedges) and 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).

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 Helicopsyche (Speckled Peters) and Caddisfly Genus Neophylax (Autumn Mottled Sedges).