PENTASTOMID INFECTIONS IN CICHLID FISHES IN THE KRUGER-NATIONAL-PARK AND THE DESCRIPTION OF THE INFECTIVE LARVA OF SUBTRIQUETRA-RILEYI N. SP

During 1995, studies were conducted on the pentastome fauna of the cic hlid fishes Tilapia rendalli and Oreochromis mossambicus in the Kruger National Park. The prevalence of infective pentastome larvae was 40,5 % in T. rendalli and 9,2% in O. mossambicus. Encapsulated nymphs of Le iperia cincinnalis were taken from the mesentery, while Sebekia wedli was either encapsulated or free-living in the swim bladder. The subtri quetrids moved about freely in the swim bladder. L. cincinnalis was pr esent in 0,5% of T. rendalli and 0,8% of O. mossambicus and additional descriptions and measurements of the nymphs are presented. S. wedli w as present in 2,5% of 0. mossambicus and a new Subtriquetra species, f or which the name Subtriquetra rileyi n. sp. is proposed, in 7,5%. Thi s ratio in T. rendalli was 40,5% and 2,2%, respectively. Of the infect ed T. rendalli, 89% harboured one or two sebekiid larvae, while a sing le fish harboured eight. Fish infected with S. rileyi contained only o ne larva each. The condition factor of infected T. rendalli was compar ed statistically to that of uninfected fish and no significant differe nce found. However, infected fish were significantly shorter and light er than uninfected ones. S. rileyi differs from the other three known Subtriquetra spp., Subtriquetra subtriquetra, Subtriquetra megacephala and Subtriquetra shipleyi in both hook size and annulus counts. Furth ermore, S. subtriquetra occurs in South American crocodilians (Riley 1 986), and S. megacephala and S. shipleyi in crocodilians in India (Fai n 1961). This is the first record of the genus occurring in Africa and although adult specimens of S. rileyi n. sp. were not obtained, we as sume that the new species is specific to Nile crocodiles.