Phylogenetic relationships elucidate colonization patterns in the intertidal grazers Osilinus Philippi, 1847 and Phorcus Risso, 1826 (Gastropoda: Trochidae) in the northeastern Atlantic Ocean and Mediterranean Sea

► We construct molecular phylogenies for all recognized Osilinus and Phorcus species. ► O. kotschyi is removed from genus Osilinus; the remaining 9 species are all assigned to Phorcus. ► Mediterranean species colonized post-MSC from the Atlantic on several occasions. ► Atlantic Island Osilinus species derived by sequential dispersal events from the mainland.