Taxonomy and Faunistics of the Helminth Parasites of Clarias gariepinus (Burchell, 1822), and Oreochromis mossambicus (Peters, 1852) from Temporary Pans and Pools in the Save-Runde River Floodplain, Zimbabwe

摘要

Two freshwater fish species, Clarias gariepinus and Oreochromis mossambicus, were collected from pans, dry-season pools, and tributaries of the Save and Runde rivers in the southeastern lowveld of Zimbabwe from December 2004 until June 2006. Helminth parasites infecting these fish were isolated from the gills, skin, muscles, body cavity, gall bladder, stomach, and intestines and were examined microscopically. Adult helminths were collected from the darter, Anhinga melanogaster, a piscivorous bird, to compare and possibly link them to the larvae recovered from fish. Stomach contents of the birds were analyzed, and their prey fish species were identified. Larval helminths collected include digenean metacercariae (clinostomes and strigeids), larval cestodes (gryporhynchids), and juvenile nematodes (Contracaecum). Adult worms include the monogeneans Macrogyrodactylus clarii, Macrogyrodactylus karibae, and Macrogyrodactylus congolensis; the digenean Clinostomum complanatum; the nematodes Paracamallanus cyathopharynx, Contracaecuni rudolphi, Contracaecum multipapillatum, and Contracaecum rodhaini; and the cestodes Polyonchobothrium clarias and Echinorhynchotaenia tritesticulata. Many of these observations are the first record of that particular parasite species in Zimbabwe or southern Africa. Morphological measurements were made and compared with the original species description, and some unique morphological features are here described.