Parasite Fauna of the Dusky Grouper (Epinephelus marginatus, Lowe 1834) from the Central Mediterranean Sea

SIMPLE SUMMARY: The dusky grouper (Epinephelus marginatus) is one of the most expensive species present in the central Mediterranean Sea and the parasite fauna of this species has not been investigated, so far. The aim of the present survey was describing the dusky grouper parasites according to fish size and parasite charge. E. marginatus specimens in two groups (cold and warm months) were also divided to establish the relation between parasite fauna and fishing period. According to the results obtained, we can speculate that the infection differences between cold and warm periods could be related to the availability of different prey representing intermediate parasites host. None of the parasites found pose a threat to humans. ABSTRACT: This study aimed to investigate parasite fauna of E. marginatus from the central Mediterranean Sea between Messina and Syracuse. In the present survey; parasite fauna of dusky grouper was investigated for two main reasons: the economic value of this species and the current lack of studies regarding the capture area. Seventy dusky groupers were caught from May 2018 to February 2020. Forty-seven out of the 70 specimens (67.2%) were infected with one or more parasite species. The most abundant species was Prosorhynchus caudovatus (42.9%), followed by Podocotyle temensis (28.6%), Didymodiclinus sp. (18.6%), Philometra jordanoi (5.7%), Anisakis Type II larvae (5.7%). Higher prevalence of infection of P. jordanoi and Contracaecum sp. was found in warm months (March to September), while P. caudovatus and P. temensis were mostly found during cold months. Weight and total length of E. marginatus were positively correlated with the parasitic load of P. jordanoi and Didymodiclinus sp. The different prevalence of parasite infection found between warm and cold months is probably related to the diet of the dusky grouper; which is characterized by mollusks that are intermediate hosts for parasite species found. None of the parasites found in the present survey is responsible for zoonosis