Diversity of digenean trematodes of Clinus superciliosus (Linnaeus, 1758) from the coast of South Africa

Abstract

To date, 87 digenean species from 63 genera of 24 families have been described or reported from marine fishes in South Africa. However, when considering the range of available hosts along this biodiversity-rich coastline, this is not all there is to be found. From these, two species have been found in the super klipfish Clinus superciliosus from Port Elizabeth: Coitocaecum capense and Helicometra fasciata. The present study aimed to further explore the trematode diversity of this endemic fish host by incorporating more and dispersed sampling localities. Specimens of C. superciliosus collected from Saldanha Bay, Cape Town harbour, Hermanus, Tsitsikamma National Park, Jeffreys Bay and Chintsa, were subjected to helminthological examination. Digenean trematodes found were characterised by molecular (28S rDNA, ITS1-5.8S-ITS2, ITS2, cox1) and morphological analyses. This revealed the presence of metacercariae belonging to four species: Cardiocephaloides physalis, Cardiocephaloides sp., Dollfustrema sp., Stephanostomum sp.; and adult specimens of ten species: Co. capense, Coitocaecum sp. 1, Coitocaecum sp. 2, Coitocaecum sp. 3, Helicometra sp. 1, Helicometra sp. 2, Hemiuridae gen. sp. 1, Hemiuridae gen. sp. 2, Proctoeces sp. and Zoogonidae gen. sp. Thus, C. superciliosus is now known to host digeneans from seven families (Acanthocolpidae, Bucephalidae, Fellodistomidae, Hemiuridae, Opecoelidae, Strigeidae and Zoogonidae). This is the first report of C. superciliosus as second intermediate host to digenean species of the families Acanthocolpidae, Bucephalidae and Strigeidae, as well as definitive host to species of the families Fellodistomidae, Hemiuridae and Zoogonidae. Except for Co. capense, all other species are reported from this fish host for the first time. This study also provides the first molecular characterisation of adult digeneans from South Africa as well as the molecular characterisation of digenean species from this fish host. The astonishing diversity of digeneans found from a single fish species, supports the theories that the marine parasite diversity in South Africa is vastly understudied, thereby highlighting the opportunity for future explorative taxonomic and biodiversity research along this coastline.