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The diversity of monogenean ectoparasites of Gyrodactylidae Cobbold, 1864 is well known with more than 440 described species worldwide. However, to date, gyrodactylids from the African continent has not been well-researched. In order to better understand the diversity of viviparous monogeneans parasitizing African cichlids, various species of cichlids were collected and examined during 2011-2013 from Zimbabwe, South Africa, Burundi and Democratic Republic of Congo. In addition viviparous parasites of northern African cichlids, originating from Sudan and Egypt were also included in the study. Thus material from four African riverine basins were examined, i.e. Limpopo River basin (Nwanedzi River, South Africa), Zambezi River basin (Zambezi River, Kariba and Chivero Lakes, Zimbabwe), Congo River basin (Lake Tanganyika, Burundi and Democratic Republic of Congo) and Nile River basin (Nile River, Sudan and Egypt). Viviparous monogeneans of the genus Gyrodactylus Nordmann, 1832 were recorded from a wide range of cichlid hosts, representing five different tribes. The tribes and infected host were as follows: Ectodini - Opthalmotilapia nasuta (Poll & Matthes, 1962); Eretmodini - Eretmodomus marksmithi Burgess, 2012; Haplochromini - Astatotilapia burtoni (Günther, 1894), Ctenochromis horei (Günther, 1894), Pharyngochromis acuticeps (Steindachner, 1866), Pseudocrenilabrus philander (Weber, 1987); Tropheini - Simochromis diaphragma (Günther, 1894), and Tilapiini - Oreochromis niloticus (L.), Tilapia rendalli (Boulenger, 1897), Tilapia sparrmanii (Smith, 1840), Tilapia zillii (Gervais, 1844) and Tilapia sp. Identification of parasite species based on haptoral sclerite morphometry and nuclear ribosomal DNA internal transcribed spacer (ITS) sequences identified 15 Gyrodactylus species. Only three of them are currently known to science i.e. Gyrodactylus nyanzae Paperna, 1973, Gyrodactylus sturmbaueri Vanhove, Snoeks, Volckaert & Huyse, 2011, and Gyrodactylus yacatli García-Vásquez, Hansen, Christison, Bron & Shinn, 2011. Identification of 10 undescribed Gyrodactylus species insinuates high diversity of these parasites in Africa. Based on the shape of the haptoral complex, species were divided into groups within each of them the species can be distinguished based on measurements of the haptoral sclerites and/or the shape of marginal hook sickles. The use of principal component analyses (PCA) helped to distinguish between the different Gyrodactylus species and their relative positions were plotted. Phylogenetic analyses, the maximum likelihood (ML) and Bayesian interference (BI), revealed interspecific relationship and evolutionary lineages indicating different origin of Gyrodactylus species parasitizing African cichlids. Study was financially supported by the projects P505/11/P470 and GBP505/12/G112 from the Grant Agency of the Czech Republic.
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