Tiny Baetis mayflies are perhaps the most commonly encountered and imitated by anglers on all American trout streams due to their great abundance, widespread distribution, and trout-friendly emergence habits.
This is a realy big, dark dragonfly nymph. Notice how "fuzzy" it is--it's covered with small hairs that collect sediment and debris and camouflage the nymph to match its natural surroundings. The greenish cast in some of the photos of this specimen is due to strange lighting during my first night photographing things for this site.