Hexabothriid monogeneans from the gills of deep-sea sharks off Algeria, with the description of Squalonchocotyle euzeti n. sp. (Hexabothriidae) from the kitefin shark Dalatias licha (Euselachii, Dalatiidae)

Abstract

SummarySharks (765 specimens from ten species) from the Mediterranean Sea off Algiers, Algeria, were examined for the presence of gill monogeneans. The following deep-sea sharks were investigated from 2009 to 2015: Centrophorus granulosus (27 specimens); Centrophorus uyato (39); Etmopterus spinax (67); Somniosus rostratus (19); Galeus melanostomus (189); Scyliorhinus canicula (261), Hexanchus griseus 3), and Dalatias licha (100). In addition, two pelagic shark species were examined: Alopias vulpinus (7), and Prionace glauca (53). Only two species of gill monogeneans were found. Protocotyle grisea (Cerfontaine, 1899) Euzet et Maillard, 1974 was found on its type-host Hexanchus griseus; comparative measurements are provided, and Algeria is a new geographic record. Squalonchocotyle euzeti n. sp. from Dalatias licha is described here. We found that the species of Squalonchocotyle Cerfontaine, 1899 can be separated into two groups, according to body size. Small-bodied species include 7 species. Large-bodied species (body > 20mm) include S. borealis (Van Beneden, 1853), S. laymani Yamaguti, 1958 and S. euzeti n. sp; the latter is distinguished from the two other species by a characteristically slender body. A sequence of Cytochrome Oxidase Type I (COI) gene, potentially useful for barcoding, was obtained for S. euzeti n. sp. and is the fi rst for the family Hexabothriidae.

Microcotyle visa n. sp. (Monogenea: Microcotylidae), a gill parasite of Pagrus caeruleostictus (Valenciennes) (Teleostei: Sparidae) off the Algerian coast, Western Mediterranean

“…Recent studies have shown that the biodiversity of monogeneans of marine fish in the southern part of the Mediterranean is far from being completely known (Chaabane et al, 2015(Chaabane et al, , 2016a(Chaabane et al, , b, 2017Chaari et al, 2016;Kheddam et al, 2016;Boudaya & Neifar, 2016;Ayadi et al, 2017). In the course of a parasitological study of monogeneans of sparid fishes off the Algerian coast, we collected representatives of an undescribed species of Microcotyle on the gills of Pagrus caeruleostictus.…”

Towards the resolution of the Microcotyle erythrini species complex: description of Microcotyle isyebi n. sp. (Monogenea, Microcotylidae) from Boops boops (Teleostei, Sparidae) off the Algerian coast

“…This paper is a part of an ongoing effort to characterise the parasite biodiversity of fish of the southern shores of the Mediterranean Sea (Ayadi et al 2017;Boudaya and Neifar 2016;Bouguerche et al 2019;Chaabane et al 2015Chaabane et al , 2016aChaabane et al , b, 2017Chaari et al 2016;Kheddam et al 2016;Kouider El Ouahed-Amine 1998).…”

A new species of Microcotyle (Monogenea: Microcotylidae) from Scorpaena notata (Teleostei: Scorpaenidae) in the Mediterranean Sea

“…Since sequences of mitochondrial cytochrome c oxidase subunit I (COI) have proven reliable for distinguishing monogenean species [12] [13], we provide new sequences for both Microcotyle species. This paper is part of a project on the monogeneans of the south shores of the Mediterranean Sea [13][14][15][16].…”