Lecithaster helodes n. sp. is described from Mugil curema and M. cephalus. It differs from the closely related L. mugilis Yamaguti, 1970 by having four rather than three ovarian lobes and other minor differences. Discussions and measurements are presented for L. confusus Odhner, 1905, L. leiostomi Overstreet, 1970, Hysterolecitha elongata Manter, 1931, Aponurus pyriformis (Linton, 1910) n. comb., and A. elongatus Siddiqi & Cable, 1960. Branchadena Linton, 1910 is considered a synonym of Aponurus Looss, 1907. New host records are listed for some of the above hemiurid trematodes. Leurodera ocyri Travassos, Frietas & Bihrnheim, 1965 and L. inaequalis Travassos, Freitas & Biihrnheim, 1965 are considered synonyms of A. pyriformis
