A New Species of Urocleidus (Trematoda: Monogenea) from Gills of the White Perch, Morone americana (Gmelin)

Urocleidus nactus sp. n. is described from the gills of the white perch, Morone americana (Gmelin), from North Carolina. Urocleidus nactus is the seventh species of Urocleidus to be described with a spurlike structure at the base of the anchor point and can be distinguished from other closely related species by the morphology of the hooks and of the accessory piece which is a 2-pronged fork. Urocleidus rogersi Hanek and Fernando 1972 is reported from the white perch, Morone americana, in North Carolina, and the white bass, Morone chrysops (Rafinesque), in North Carolina and Nebraska. Morphological variation of the accessory piece is described and a new interpretation of the haptoral armament is presented.