My friend Willy captured this early instar damselfly nymph and brought it to me for identification. It is more robust and stocky at this early stage than the spindly appearance of the later instars, and its appearance is less familiar.
The trout in Wisconsin on July 3, 2008 were eating the fly's as they emerged. Gosh they make a ruckus as they took to the air. They only emerged under a very low bridge, not upstream or downstream from the bridge. I've never witnessed this before.