Anilocra capensis has a smooth, slate-grey carapace, with a five-segmented pleon. The head bears short antennae and is triangular, the telson is rounded. The legs end in powerful hooks that are used to grip the parasitized fish. The well-developed uropods often extend well beyond the body. The species can grow quite large and may reach a length of 60 mm.[2]
The members of the family Cymothoidae are commonly referred to as "fish lice" (although this term is also used for the family Argulidae, which are also crustaceans but not closely related). Like all Cymothoidae, A. capensis is an ectoparasite that attaches to a larger host and feeds off its body fluids. The species parasitizes fish, preferentially the hottentot Pachymetopon blochii, a mid-sized sea bream common in shallow-water kelp beds on the southern African coast. The isopod attaches itself to the fish's head above and behind the eye, rasps a hole into the skin, and consumes blood and other body juices. It was found that the size of A. capensis individuals and the hottentot it parasitizes were positively correlated, indicating that both host and parasite grow together. Both length and weight of parasitized fish were found to be slightly below those of unaffected fish, which suggests that host condition suffers to some extent from the presence of the isopod.[4]
^Branch, G. M.; Griffiths, C. L.; Branch, M. L.; Beckley, L. E. (2010). Two Oceans: a Guide to the Marine Life of Southern Africa. Cape Town: Struik Nature.
^Kensley, Brian (1978). Guide to the marine isopods of southern Africa. South Africa Museum. ISBN0-908407-43-2.
^Wright, R.V.; Lechanteur, Y.A.R.G.; Prochazka, K.; Griffiths, C.L. (2001). "Infection of hottentot Pachymetopon blochii by the fish louse Anilocra capensis (Crustacea: Isopoda) in False Bay, South Africa". African Zoology. 36 (2): 177–183. doi:10.1080/15627020.2001.11657135.
