hellgrammite

/ˈhɛlɡrəˌmaɪt/
noun
  1. The aquatic larva of a dobsonfly, used as fishing bait; also spelled hellgrammiate.
    • The bait shop sold hellgrammites in small containers.
    • A live hellgrammite wiggles vigorously on the hook.
    • He dug under a river rock and found a hellgrammite.