Freshwater Invertebrate Underwater Pictures, Page 5

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 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).

A big crayfish lurks under a log.

In this picture: Arthropod Order Decapoda (Crayfish).

This log houses several Ephemerella mayfly nymphs and, on the top right, an Epeorus mayfly nymph.

In this picture: Mayfly Species Ephemerella invaria (Sulphur Dun) and Mayfly Genus Epeorus (Little Maryatts).

This isn't really an underwater picture, but a picture taken into my aquarium of midge larvae which lived in the silt I used for substrate. Each larva has a little tower of detritus (Detritus: Small, loose pieces of decaying organic matter underwater.) built up along the bottom, while the bare larva waves around from the top.

In this picture: True Fly Family Chironomidae (Midges).