Altolamprologus compressiceps is a species of fish in the family Cichlidae, endemic to the shallow rocky areas of Lake Tanganyika. The lake holds at least 250 species of cichlid fish, including species yet to be described. Almost all (98 percent) of Tanganyika cichlid species are endemic to the lake, and it is thus an important biological resource for the study of speciation in evolution. A. compressiceps is categorized as a least-concern species by the International Union for Conservation of Nature. This fish was photographed at the Karlsruhe Zoo in Germany.Photograph credit: H. Zell