''Anilocra capensis'' is a species of

parasitic Parasitism is a close relationship between species, where one organism, the parasite, lives on or inside another organism, the host, causing it some harm, and is adapted structurally to this way of life. The entomologist E. O. Wilson ha ...

isopod Isopoda is an order of crustaceans that includes woodlice and their relatives. Isopods live in the sea, in fresh water, or on land. All have rigid, segmented exoskeletons, two pairs of antennae, seven pairs of jointed limbs on the thorax, an ...

in the family

Cymothoidae The Cymothoidae are a family of isopods in the suborder Cymothoida found in both marine and freshwater environments. Cymoithoids are ectoparasites, usually of fish, and they include the bizarre "tongue-biter" ('' Cymothoa exigua''), which attach ...

. It is endemic to southern Africa. The species preferentially attaches itself to the hottentot seabream.

Description

''Anilocra capensis'' has a smooth, slate-grey carapace, with a five-segmented

pleon The decapod (crustaceans such as a crab, lobster, shrimp or prawn) is made up of 20 body segments grouped into two main body parts: the cephalothorax and the pleon (abdomen). Each segment may possess one pair of appendages, although in various g ...

. The head bears short antennae and is triangular, the

telson The telson () is the posterior-most division of the body of an arthropod. Depending on the definition, the telson is either considered to be the final segment of the arthropod body, or an additional division that is not a true segment on accou ...

is rounded. The legs end in powerful hooks that are used to grip the parasitized fish. The well-developed

uropods Uropods are posterior appendages found on a wide variety of crustaceans. They typically have functions in locomotion. Definition Uropods are often defined as the appendages of the last body segment of a crustacean. An alternative definition sugge ...

often extend well beyond the body. The species can grow quite large and may reach a length of 60 mm.

Distribution

The species occurs on the coast of southern Africa, from the west coast at

Walvis Bay Walvis Bay ( en, lit. Whale Bay; af, Walvisbaai; ger, Walfischbucht or Walfischbai) is a city in Namibia and the name of the bay on which it lies. It is the second largest city in Namibia and the largest coastal city in the country. The c ...

Namibia Namibia (, ), officially the Republic of Namibia, is a country in Southern Africa. Its western border is the Atlantic Ocean. It shares land borders with Zambia and Angola to the north, Botswana to the east and South Africa to the south and e ...

to the east coast at

East London East or Orient is one of the four cardinal directions or points of the compass. It is the opposite direction from west and is the direction from which the Sun rises on the Earth. Etymology As in other languages, the word is formed from the fa ...

South Africa South Africa, officially the Republic of South Africa (RSA), is the southernmost country in Africa. It is bounded to the south by of coastline that stretch along the South Atlantic and Indian Oceans; to the north by the neighbouring count ...

Ecology

The members of the family Cymothoidae are commonly referred to as "fish lice" (although this term is also used for the family

Argulidae The family Argulidae, whose members are commonly known as carp lice or fish lice, are parasitic crustaceans in the class Ichthyostraca. It is the only family in the monotypic subclass Branchiura and the order Arguloida, although a second family, ...

, which are also

crustacean Crustaceans (Crustacea, ) form a large, diverse arthropod taxon which includes such animals as decapods, seed shrimp, branchiopods, fish lice, krill, remipedes, isopods, barnacles, copepods, amphipods and mantis shrimp. The crustacean gro ...

s but not closely related). Like all Cymothoidae, ''A. capensis'' is an

ectoparasite Parasitism is a close relationship between species, where one organism, the parasite, lives on or inside another organism, the host, causing it some harm, and is adapted structurally to this way of life. The entomologist E. O. Wilson ha ...

that attaches to a larger host and feeds off its body fluids. The species parasitizes fish, preferentially the hottentot ''

Pachymetopon blochii ''Pachymetopon blochii'', the hottentot seabream or hottentot, is a species of sea bream in the family (biology), family Sparidae, native to the southwestern coast of Africa. Description ''Pachymetopon blochii'' has a bronzy grey color, with dar ...

'', a mid-sized

sea bream The Sparidae are a family of fish in the order Perciformes, commonly called sea breams and porgies. The sheepshead, scup, and red seabream are species in this family. Most sparids are deep-bodied compressed fish with a small mouth separated by a ...

common in shallow-water

kelp Kelps are large brown algae seaweeds that make up the order Laminariales. There are about 30 different genera. Despite its appearance, kelp is not a plant - it is a heterokont, a completely unrelated group of organisms. Kelp grows in "under ...

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.

References

{{Taxonbar, from=Q2665419 Cymothoida Taxa named by William Elford Leach Crustaceans described in 1818 Crustaceans of South Africa