Molecular phylogeny and histopathological studies of Gotocotyla secundus (Monogenea: Polyopisthocotylea) isolated from Narrow-barred Spanish mackerel, Scomberomorous commerson in Suez Governorate, Egypt

Abstract

The family Scombridae consists of 15 genera and 49 species of epipelagic marine fishes (mackerels, bonitos and tunas). These fish are of commercial and recreational importance throughout the world's fisheries (Murugesh, 1995). The Egyptian Mediterranean waters have two species of this genus, Scombermorus tritor, (Cuvier and Valenciennes, 1832) -(first record) a species native to the Atlantic, can be spotted in the Canary Islands, Senegal, Gulf of Guinea, and Angola . Scombermorus commerson is a Red Sea immigrant from the Indo-West Pacific (Lester et al., 2001; Pauly and Froese, 2016) migrated to the eastern Mediterranean Sea by the way of the Suez Canal. El Sayed (1994) and Rizkalla (1997) recorded this species in Egyptian waters. The gill apparatus of a mackerel, a common habitat for ectoparasites, is composed of five paired units: the pseudobranch, attached to the operculum and four regular gill arches. Pelagic fishes, such