Diane Blair demonstrates how to tie Michael Verduin’s Mighty Mite Hellgrammite fly in this fly tying video demonstration. What’s A Hellgrammite Hellgrammites are the aquatic immature (larval) stage of the Dobsonfly. The lifespan of the hellgrammite ranges from 2 to 5 years which constitutes the majority of a Dobsonfly lifespan for the pupal stage lasts…