Parasites of Anemonefish (Pomacentridae, Amphiprioninae) in the Gulf of Nha Trang, South China Sea, Vietnam

In summer and autumn 2016-2017, the parasitic fauna in four anemonefish species (Amphiprionclarckii (53 ind.), A. polymnus (58 ind.),A. perideraion (15 ind.), and A. frenatus (10 ind.) (Pomacentridae)) from the areas close to Nha Trang, South China Sea, Vietnam, were studied. In total 11 parasite species were found in the studied fish with 3-8 parasite species per fish species. The survey revealed two species of copepods (Hatschekia sp. 1 and Hatschekia sp. 2), six digeneans (Macvicaria sp. 1, Macvicaria sp. 2, Aponurus piriformis,Aponurus laguncula, Hysterolecitha nahaensis, Bivesicula sp. metacercariae), two nematodes (Spirocamallanus istiblenni and Hysterothylacium sp. J4), and one acanthocephalan (Echinorhynchus sp.). The trematode Hysterolecitha nahaensis and the nematode Spirocamallanus istiblenni were the most abundant and prevalent parasites. These parasites reached a prevalence of 64% and 90% with an intensity of infection of 1-6 ind. and 1-37 ind., respectively. Two ectoparasite taxa were found: Hatschekia sp. 1 (a single specimen found in A.clarckii) and Hatschekia sp. 2. Among them, Hatschekia sp. 2 was the most frequent and abundant species in A. polymnus (prevalence 96.6%, intensity of infection 0-51).