I didn't manage to collect a nymph, but here's the hollow shuck left over from an emerged dun, showing the basic pattern of the nymph. From the West Branch of the Delaware River in New York.
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I didn't manage to collect a nymph, but here's the hollow shuck (

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Here's an underwater view of the pupal shucks of several already-emerged Brachycentrus numerosus caddisflies.
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.) left over from an emerged dun, showing the basic pattern of the nymph.

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