Ecto- and endoparasites of clariids in the Upper Congo Basin (DR Congo): Examining diversity

Abstract

The understanding of the parasite fauna of clariids in the Upper Congo Basin remains limited. In the past decade, heightened interest in fish parasites has led scientists to document and describe several parasite species (metacercariae from members of Clariidae; monopisthocotyleans from members of Cichlidae, Clariidae and Claroteidae), in the Upper Congo Basin. Monopisthocotyleans have been targeted for parasitological studies as they are highly host specific, ubiquitous and have a direct lifecycle, and they are not well studied in many ecoregions in the Upper Congo Basin, an area with a great fish diversity. Few studies have been done, mainly on cichlids, in the Bangweulu Mweru, Tanganyika, and Upper Lualaba ecoregions. Continued studies on monopisthocotyleans and other parasite groups have yielded additional insights into parasite diversity in the Upper Congo Basin, uncovering the presence of representatives of various taxa such as Monopisthocotyla, Digenea, Cestoda, and Nematoda. Five clariids (Clarias ngamensis, C. stappersii, C. buthupogon, C. theodorae and C. gariepinus) were screened for ecto- and endoparasites in 10 localities in the Lufira and Luapula river systems. Ectoparasites: Monopisthocotyla [13 species: on C. ngamensis (Quadriacanthus aegypticus, Q. allobychowskiella, Q. amakaliae, Q. halajiani, Q. domatanai, Q. lubandaensis, Q. curvicirrus, Quadriacanthus sp. ‘shigoleyae’, Macrogyrodactylus clarii, Gyrodactylus sp. 1); on C. stappersii (Q. amakaliae, Q. sp. ‘kalomboi’, Quadriacanthus sp. ‘bassocki’); on C. buthupogon (Q. amakaliae, Quadriacanthus sp. ‘bassocki’; Gyrodactylus sp. 2); on C. theodorae (Quadriacanthus sp. ‘bassocki’); on C. gariepinus (Quadriacanthus sp. ‘bassocki’)]; Endoparasites: Digenea (in C. ngamensis: Clinostomum brieni), Cestoda (in C. stappersii: metacestodes of Gangesinae), Nematoda (in C. gariepinus: Camallanus sp.) have been recorded. These results highlight the potential biodiversity still to be explored in the Upper Congo Basin and it will serve as an important baseline for future studies.