Abstract:
Two species of the Accacoeliidae Odhner, 1911, Accacoelium contortum (Ruldolphi, 1819) and Accacladocoelium petasiporum (Odhner, 1928), are redescribed based on new materials collected from the intestine of the sharptail mola Masturus lanceolatus (Lienard) off the coast of Hainan Island in the South China Sea. Characteristics of uterus of the two species are different from previous descriptions, and the specimens of A. contortum were collected in intestine rather than gills as reported previously. Both of these two species and their genera are firstly recorded in China.