Myzobdella lugubris. (A) burrowing into the buccal mucosa of a largemouth bass (arrow) from Orion Lake; (B) ulcerations and leeches (arrows) in the roof of the mouth of a largemouth bass from Orion Lake; (C) severe ulceration associated with a leech infestation in the roof of the mouth of a largemouth bass from Devils Lake with suppurative inflammation and subsequent pus formation (arrow); and (D) M. lugubris (arrow) attached to the tongue of a largemouth bass from Devils Lake.