Metazoan parasites of trachinid fishes (Teleostei: Trachinidae) from Tunisian coasts (Mediterranean Sea)

Trachinids (Teleostei: Trachinidae) are a family of benthic marine fish living on sandy or muddy bottoms, typically on the continental shelf but also in deeper waters of 150 to 200 m. These fish have a wide distribution through the eastern Atlantic coasts, Mediterranean Sea and Black Sea. In Tunisia, the most commonly known species of trachinids are: the greater weever, (Trachinus draco), the spotted weever, (Trachinus araneus) and the starry weever (Trachinus radiatus). Several studies have been performed on the metazoan parasites of trachinids through the word (DILLON & HARGIS, 1965; ORRECHIA & PAGGI, 1978; GEORGES, 1982; PETTER & MAILLARD, 1988; TRILLES et al., 1989; CANNING et al., 1999; HORTON, 2000; AKMIRZA, 2004; ÖKTENER & TRILLES, 2004; FARJALLAH et al., 2008). Nevertheless, in Tunisia, only two studies have been achieved on trachinid fishes, AZIZI et al. (2016) described a new species of myxosporean Zschokkella trachini from the gallbladder of Trachinus draco and FARJALLAH et al. (2008) who reported the nematode Anisakis pegreffi parasite of T. draco. Parasitic diseases may influence weight, reproduction, growth and survival of the host, inducing significant economic losses in fish production particularly in aquaculture. Therefore, data on biodiversity and ecology of parasites in natural ecosystems, the nature of the host/parasite relationship and the possible use of parasites as biological tags are very important in terms of conservation. In order to expand our knowledge on the biodiversity of trachinids parasites, we have undertaken a parasitological A parasitological survey of Trachinus draco Linnaeus, 1758; Trachinus araneus Cuvier, 1829 and Trachinus radiatus Cuvier, 1829 collected from Tunisian coasts was performed from January 2014 to January 2015. In total, 18 species of metazoan parasites belonging to 13 genera were found: nine Myxozoa, four Nematoda, one Cestoda, one Digenea, one Monogenea, one Isopoda and one Annelida Hirudinea. Data on morphology, location and infection levels of parasites were provided. The higher species richness was recorded in Trachinus draco (18 species), while Trachinus radiatus and Trachinus araneus harbored 9 and 7 species, respectively. Species richness and diversity according to the host species and the sampling sites based on the Simpson and Shannon-Wiener indices are reported.