Unique co-occurrence of two genera of cymothoid ectoparasitic isopods on the same individual fish host

Abstract

Parasitism of a host fish by a single species of cymothoid is regularly reported. For the first time on a temperate-fish host and in South African waters, we observed two species of cymothoids, the flesh-infesting Anilocra capensis and the tongue-infesting Ceratothoa africanae, simultaneously infesting the same individual hottentot seabream Pachymetopon blochii. Each P. blochii harboured an ovigerous and non-ovigerous A. capensis and an ovigerous and non-ovigerous C. africanae. Cymothoid co-occurrence is rarely reported, and this is the first report of two cymothoid species infesting a single fish host from Africa. Globally, it is the first record of flesh- and tongue-infesting cymothoids parasitising the same individual fish.