Some parasitic worms in freshwater fishes and fish-predators from the Transvaal, South Africa.
Several species of helminths are reported from freshwater fishes and their predators from the Transvaal, South Africa. Gyrodactylus transvaalensis n.sp. from the skin of Clarias gariepinus differs from African species of Gyrodactylus with a single row of spines on the cirrus in the shape and and size of its anchors. It also lacks a membrane to the transverse ventral bar of the opisthaptoral armature. One specimen, closely resembling G. transvaalensis except for its greater measurements, is thought to be a giant form of the new species. Phyllodistomum vanderwaali n.sp. from the urinary bladder of C. gariepinus most resembles P. linguale but differs in the smaller body and eggs, and in the shape and orientation of the vitelline bodies. The following were also recovered and are described: Acanthostomum productum from the intestine of Crocodylus niloticus; Nephrostomum ramosum from Ardea cinerea, the body shape of which differs slightly from the norm; Euclinostomum heterostomum adult from A. cinerea and metacercariae from Sarotherodon (Tilapia) mossambicus; Euclinostomum metacercariae from Clarias gariepinus; Apharyngostrigea cornu from Ardea cinerea (new geographical record); Pseudoneodiplostomum bifurcatum from Crocodylus niloticus; diplostome metacercariae from Clarias gariepinus; Ligula intestinalis and Paradilepis delachauxi from Phalacrocorax africanus; and Contracaecum larvae in Clarias gariepinus. The taxonomy of several of these species is discussed and Nephrostomum legonum is synonymized with N. ramosum.