Paracaesicola nanshaensis n. gen., n. sp. (Monogenea, Microcotylidae) a gill parasite of Paracaesio sordida (Teleostei, Lutjanidae) from the South China Sea

Novel molecular data for monogenean parasites of sparid fishes in the Mediterranean and a molecular phylogeny of the Microcotylidae Taschenberg, 1879

During a study of the monogeneans of four sparid fishes (Diplodus vulgaris, Pagellus bogaraveo, Pagrus pagrus and Sparus aurata) from the Western Mediterranean off Algeria, a large collection of parasites was characterised molecularly (28S rRNA and cox1 genes). A total of 46 partial sequences (23 for each gene) were generated from 38 isolates of monogeneans which included four species (Atrispinum acarne, Microcotyle erythrini (sensu stricto), Sparicotyle chrysophrii and Prostatomicrocotylinae gen. sp.) of the family Microcotylidae, two putative species of the family Capsalidae (Encotyllabe spp.), and one species (Choricotyle chrysophryi) of the family Diclidophoridae. Our study provides (i) the first molecular data for the Capsalidae in the Mediterranean; (ii) the first record of a member of the Prostatomicrocotylinae in the Mediterranean and in a sparid fish (D. vulgaris); (iii) the first cox1 sequences for A. acarne; (iv) the second record of M. erythrini (s.s.) from P. pagrus; and (v) the second confirmed by molecular data record of S. chrysophrii in wild populations of S. aurata. The first phylogenetic hypotheses for the family Microcotylidae developed here, revealed the monophyly of the subfamily Prostatomicrocotylinae and the genus Microcotyle but the relationships among the subfamilies were still largely unresolved with the best represented subfamily Microcotylinae being polyphyletic. Our results highlight the importance of molecular methods in the assessment of monogenean diversity and the need for a thorough taxon-sampling approach to increase the accuracy of phylogenetic reconstruction of the relationships of the large and taxonomically complex polyopisthocotylean family Microcotylidae.