Parasites of South African freshwater fish. II. Redescription of the African species of the genus Phyllodistomum Braun, 1899 (Trematoda: Gorgoderinae) and the description of a new species.

During 1980 a survey of the parasites of freshwater fish was conducted in the Sabie and Crocodile Rivers in the southern part of the Kruger National Park, Transvaal. A new species of Phyllodistomum, Braun, 1899, for which the name Phyllodistomum bavuri is proposed, was found in the urinary bladder of many of the catfish, Clarias gariepinus (Burchell, 1822), examined. The new species resembles Phyllodistomum linguale Odhner, 1902 and Phyllodistomum vanderwaali Prudhoe & Hussey, 1977, but may be differentiated from the former species in that the ovary and the vitellaria are smooth, while those of P. linguale are irregularly lobed. The ovary of P. vanderwaali is irregularly lobed while that of P. bavuri never has more than 3 indistinct lobes. In addition, P. bavuri is much larger than P. vanderwaali. P. bavuri is readily differentiated from the other 4 African species of Phyllodistomum, namely, Phyllodistomum spatula (Odhner, 1902), Phyllodistomum spatulaeforme (Odhner, 1902), Phyllodistomum ghanense Thomas, 1958 and Phyllodistomum symmetrorchis Thomas, 1958. For comparative purposes the African species are briefly redescribed and illustrated. P. bavuri occurred throughout the year and their numbers do not appear to fluctuate seasonally in the Kruger National Park.