Comparative scanning electron microscopical studies were carried out on Chonopeltis australis Boxshall, 1976 collected from different localities in the Orange-Vaal River System in South Africa and on material of Chonopeltis minutus Fryer, 1977 and Chonopeltis australissimus Fryer, 1977 on loan from the Albany Museum, Grahamstown. This elucidates the fine structure of morphological features, which are of taxonomic importance and illustrates the significance of the copulatory structures on the legs as a taxonomic tool. It was also concluded that C. australissimus is the same as C. minutus, with C. australissimus the junior synonym.
A new species Chonopeltis liversedgei sp. n. of the endemic African genus Chonopeltis Thiele, 1900 (Crustacea: Branchiura) is described. T his ectoparasite inhabits the branchial chamber of its mormyrid host Mormyrus lacerda Castelnau, 1861 and was collected from three localities in the Okavango River and its inland Delta in Botswana, Southern Africa.
Current records of marine myxozoans from the coast of Africa are limited to the descriptions of 52 species from mostly Senegal, with a few from Tunisia and southern Africa. Between 1998 and 2000 several intertidal fishes from the southern Cape coast of South Africa were examined for the presence of myxozoan infections. Three new species, Ceratomyxa dehoopi sp. n., C. cottoidii sp. n. and C. honckenii sp. n. were identified from the gall bladders of Clinus superciliosus L., C. cottoides Valenciennes and Amblyrhynchotes honckenii (Bloch), respectively. A fourth new species Henneguya clini sp. n. was also identified from the gills and gill arches of C. superciliosus.
Fieldwork was conducted in 1998 and 1999 in the Okavango River and Delta and a total of 275 fishes representing 31 species were examined for the presence of myxosporean parasites. A total of seven myxosporeans of the genus Myxobolus Bütschli, 1882 were found infecting the fishes. Two new species namely Myxobolus etsatsaensis sp. n. from Barbus thamalakanensis Fowler, 1935 and M. paludinosus sp. n. from Barbus paludinosus Peters, 1852 are described. Myxobolus africanus Fomena, Bouix et Birgi, 1985, M. camerounensis Fomena, Marqués et Bouix, 1993, M. hydrocyni Kostoïngue et Toguebaye, 1994, M. nyongana (Fomena, Bouix et Birgi, 1985) and M. tilapiae Abolarin, 1974 are recorded for the first time in Botswana and descriptions of these species are provided.
During a recent investigation of parasites infecting fishes from the Okavango River and Delta, Botswana (southern Africa) fourteen sharptooth catfish, Clarias gariepinus (Burchell, 1822) (Siluriformes: Clariidae) were examined for the presence of myxozoan infections. Results revealed the presence of two species of the genus Henneguya Thélohan, 1895 and one species of the genus Myxobolus Bütschli, 1882 infecting this fish host. Two of the sampled fish exhibited large plasmodia of Henneguya suprabranchiae Landsberg, 1987 in the cartilage of the accessory breathing organ, another two individuals were infected with H. samochimensis sp. n. plasmodia in the gills and another three individuals revealed an infection with Myxobolus gariepinus sp. n. plasmodia in the ovaries.