| Description |
Parasites of the genus Gyrodactylus von Nordmann, 1832 are distributed worldwide. In the recent past, studies focused mainly on hosts which are important for the aquaculture, but recently the interest expanded which enabled deeper knowledge on the variety and phylogenetic traits of this highly diverse parasitic group. An increasing amount of available data on the distribution of these parasites allows revalidation regarding host specificity, preferences of site of infection and relationship within phylogenetic lineages. The present study includes data from several surveys. The majority of the samples were collected during 2011-2015 in Burundi, Democratic Republic of Congo, South Africa, Sudan and Zimbabwe. Collected hosts were examined for the presence of Gyrodactylus. Infected host tribes and species belongs to: Ectodini - Opthalmotilapia nasuta; Eretmodini - Eretmodomus marksmithi; Haplochromini - Astatotilapia burtoni, Ctenochromis horei, Pharyngochromis acuticeps, Pseudocrenilabrus philander; Tropheini - Simochromis diaphragma, and Tilapiini - Oreochromis niloticus, Coptodon rendalli, Tilapia sparrmanii, Tilapia zillii and Tilapia sp. Identification of parasite species was based on the morphometric analyses of attachment organ hard parts and molecular analyses of nuclear ribosomal DNA internal transcribed spacer (ITS) sequences. In total, 16 species of Gyrodactylus were recognized, Gyrodactylus sp. 1-8, G. chitandiri, G. nyanzae, G. occupatus, G. parisellei, G. sturmbaueri, G. thysi, G. thlapi and G. yacatli. Maximum likelihood (ML) and Bayesian interference (BI) were used for the evaluation of phylogenetic relationships between parasitic species. Morphometric characteristic were visualized via Principal Component Analyses (PCA) what allows simplified interpretation of crucial patterns in attachment organ hard parts of specimens. Results of the present study demonstrate a relationship between hard parts of attachment organ and molecular sequences, patterns in host/geographical distribution and also the importance of using integrative approach during parasite idnetification.
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