The Hellgrammite. It looks nasty and I wouldn’t touch it. Most of you have seen this bug but have no clue what it is. If you’re flipping rocks at just about any river in Maine you will find the larva form of this, which all fish love to eat.
A quick search I found this at : http://entnemdept.ufl.edu/creatures/misc/eastern_dobsonfly.htm
The eastern dobsonfly, Corydalus cornutus (Linnaeus), is one of our largest non-lepidopteran insects. Its larvae, known as hellgrammites, are the top invertebrate predators in rocky streams where they occur. Adult male dobsonflies are particularly spectacular because of their large sickle-shaped mandibles (jaws). There is a total of thirty species of Corydalus (Contreras-Ramos 1997), mostly from South America. In addition to the eastern dobsonfly, Corydalus cornutus, there are three dobsonflies of the genus Corydalus in the western U.S. For simplicity, the term “dobsonfly” throughout the remainder of this publication will refer to the eastern dobsonfly, Corydalus cornutus.
A brown woolly bugger is perfect to match the larvae.
The adult is often mistaken for a adult stone fly! I have never seen a fish eat the adult but I know trout and bass feed on the larva heavily.
Kevin McKay and Stacy Chiasson