screwworm

screw worm |ˈskro͞oˌwərm ˈskruˌwərm | ▶noun a large American blowfly larva that enters the wounds of mammals, developing under the skin and often causing death. The adult fly is called the screwworm fly. [Cochliomyia (or Callitroga ) hominivorax, family Calliphoridae. ]