Altolamprologus calvus is a cichlid

Cichlid

Cichlids are fishes from the family Cichlidae in the order Perciformes. Cichlids are members of a group known as the Labroidei along with the wrasses , damselfish , and surfperches . This family is both large and diverse. At least 1,300 species have been scientifically described, making it one of...

 endemic to the southern shoreline of Lake Tanganyika

Lake Tanganyika

Lake Tanganyika is an African Great Lake. It is estimated to be the second largest freshwater lake in the world by volume, and the second deepest, after Lake Baikal in Siberia; it is also the world's longest freshwater lake...

 in eastern Africa

Africa

Africa is the world's second largest and second most populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area...

. The species has an extremely laterally compressed body and a high dorsal fin

Dorsal fin

A dorsal fin is a fin located on the backs of various unrelated marine and freshwater vertebrates, including most fishes, marine mammals , and the ichthyosaurs...

. Males may grow to 13 cm (5 inches), while females are normally smaller.

It is physically similar to its close relative A. compressiceps

Altolamprologus compressiceps

Altolamprologus compressiceps is a species of fish in the Cichlidae family. It is found in Burundi, the Democratic Republic of the Congo, Tanzania, and Zambia. Its natural habitat is freshwater lakes. It is not considered threatened by the IUCN....

, though it is less deep-bodied and has a longer snout.

A. calvus is commonly kept as an aquarium

Aquarium

An aquarium is a vivarium consisting of at least one transparent side in which water-dwelling plants or animals are kept. Fishkeepers use aquaria to keep fish, invertebrates, amphibians, marine mammals, turtles, and aquatic plants...

 fish

Fish

Fish are a paraphyletic group of organisms that consist of all gill-bearing aquatic vertebrate animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish, as well as various extinct related groups...

 in setups devoted to East African fish. Several local variants exist, and some may prove to be distinct species

Species

In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

 or subspecies

Subspecies

Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...

. Examples include:

• 'Black Sambia'
• 'Black Pectoral'
• 'Black Zaire'
• 'Black Kapampa'
• 'Yellow'
• 'White'
• 'Red Fin'