The giant Salmonflies of the Western mountains are legendary for their proclivity to elicit consistent dry-fly action and ferocious strikes.
The bugs they collected were very large. I'd say maybe two inches long was the body, and a big, dragonfly nymph is maybe an inch long is it not?
Jason,..Wish I were better on this darn computer, because I could have emailed the host of that show
The Green Darner (Anax junius) is a common and widespread species of dragonfly with mature nymphs as large as 50-55mm (or about 2").