Caddisfly adults resemble moths, but when resting they fold their wings over their back, and they don't have scales on their wings as butterflies or moths do. The aquatic larvae of dragonflies and damselflies metamorphose into the elegant, winged creatures you've probably seen near streams, rivers, and lakes. The larva itself is a rather bizarre looking creature. It is elongated and gray, black, brown, orange or green in color. You'll find these insects in submerged vegetation or in the bank regions of streams and ponds.
Large logs are also good collection sites.
Burrowing forms sometimes make trails in sandy, backwater areas. You might sight trails along the stream banks in shallow areas. Fly and midge adults are not aquatic, but many have immature stages which live in water. Fly and midge larvae occur in every type of freshwater environment. Aquatic diptera larvae are more varied in body structure than any other groups of aquatic insects.