| Description |
Freshwaters of Afrotropical Region harbour more than 200 characiform fishes (Characiformes) currently arrayed in four families: Alestidae (118 species), Citharinidae (8 species), Distichodontidae (101 species), and Hepsetidae (5 species). Alestidae, often called African tetras, are known to be parasitized by ectoparasitic flatworms (Monogenea: Dactylogyridae) representing three genera: Annulotrema (41 species), Characidotrema (10 species), and Afrocleidodiscus (1 species, namely A. hydrocynuous). During field trips (2007 – 2017) we sampled 11 species of African tetras (Alestes baremoze, A. dentex, Arnoldichthys spilopterus, Brycinus imberi, B. leuciscus, B. nurse, Hydrocynus forskahlii, H. brevis, H. vittatus, Micralestes accutidens, M. elongatus) from eight African countries (Cameroon, Democratic Republic of the Congo, Kenya, Nigeria, Senegal, South Africa, Sudan, and Zimbabwe). Our investigation of parasite diversity of African tetras revealed the presence of monogeneans belonging to two genera within the Dactylogyridae: Annulotrema (19 species), and Characidotrema (6 species). Preliminary phylogenetic analyses supporting morphological data confirmed the monophyly of Characidotrema species, while species of Afrocleidodiscus hydrocynuous and representatives of Annulotrema clustered together. Afrocleidodiscus paracleidodiscus from Distichodus rostratus (Characiformes: Distichodontidae) forms separate cluster close to the Characidotrema spp. Division of both Afrocleidodiscus species highlights the necessity of revising the genus. The presence of haptoral bars with supporting membranes provides an additional supportive character for transfer of A. hydrocynuous to Annulotrema.
|
