Well, you learn something new every day!
I was going to go straight to the bottom of the page and post "Hey, everyone - it's a hellgamite!"
Turns out they're the same thing - never heard them called Dobson fly larvae before, though.
I used to have a friend whose family had a cabin on the Allegheney River - that place was full of hellgamites - and yes - once a year, they sprout wings and fly around!!
