''Steatocranus'' is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

of small

rheophilic A rheophile is an animal that prefers to live in fast-moving water. Examples of rheophilic animals Insects *Many aquatic insects living in riffles require current to survive. *''Epeorus sylvicola'', a rheophilic mayfly species ( Ephemeroptera) ...

cichlid Cichlids are fish from the family Cichlidae in the order Cichliformes. Cichlids were traditionally classed in a suborder, the Labroidei, along with the wrasses ( Labridae), in the order Perciformes, but molecular studies have contradicted this ...

s mostly native to the

Congo River Basin The Congo River ( kg, Nzâdi Kôngo, french: Fleuve Congo, pt, Rio Congo), formerly also known as the Zaire River, is the second longest river in Africa, shorter only than the Nile, as well as the second largest river in the world by discharge ...

DR Congo The Democratic Republic of the Congo (french: République démocratique du Congo (RDC), colloquially "La RDC" ), informally Congo-Kinshasa, DR Congo, the DRC, the DROC, or the Congo, and formerly and also colloquially Zaire, is a country in ...

Congo Brazzaville The Republic of the Congo (french: République du Congo, ln, Republíki ya Kongó), also known as Congo-Brazzaville, the Congo Republic or simply either Congo or the Congo, is a country located in the western coast of Central Africa to the w ...

, although one

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

, '' S. irvinei'', is restricted to the

Volta River The Volta River is the main river system in the West African country of Ghana. It flows south into Ghana from the Bobo-Dioulasso highlands of Burkina Faso. The main parts of the river are the Black Volta, the White Volta, and the Red Volta. In ...

Ghana Ghana (; tw, Gaana, ee, Gana), officially the Republic of Ghana, is a country in West Africa. It abuts the Gulf of Guinea and the Atlantic Ocean to the south, sharing borders with Ivory Coast in the west, Burkina Faso in the north, and To ...

and

Burkino Faso Burkina Faso (, ; , ff, 𞤄𞤵𞤪𞤳𞤭𞤲𞤢 𞤊𞤢𞤧𞤮, italic=no) is a landlocked country in West Africa with an area of , bordered by Mali to the northwest, Niger to the northeast, Benin to the southeast, Togo and Ghana to the ...

, and it belongs in a separate genus.Dunz, A.R., and Schliewen, U.K. (2013). Molecular phylogeny and revised classification of the haplotilapiine cichlid fishes formerly referred to as “Tilapia”. Molecular Phylogenetics and Evolution, online 29 March 2013. doi:10.1016/j.ympev.2013.03.015 There are also at least 10

undescribed species In taxonomy, an undescribed taxon is a taxon (for example, a species) that has been discovered, but not yet formally described and named. The various Nomenclature Codes specify the requirements for a new taxon to be validly described and named. U ...

in the Congo River basin awaiting scientific description. The fish in this genus all have relatively reduced

swim bladder The swim bladder, gas bladder, fish maw, or air bladder is an internal gas-filled Organ (anatomy), organ that contributes to the ability of many bony fish (but not cartilaginous fish) to control their buoyancy, and thus to stay at their curren ...

function. The name ''Steatocranus'' refers to the fatty deposit on the forehead of most species. Steatocranus casuarius young

Two species, '' S. casuarius'' (also known as the lionhead or buffalohead cichlid) and '' S. tinanti'' are relatively common in the

aquarium An aquarium (plural: ''aquariums'' or ''aquaria'') is a vivarium of any size having at least one transparent side in which aquatic plants or animals are kept and displayed. Fishkeepers use aquaria to keep fish, invertebrates, amphibians, aq ...

trade. As for other cichlids brood care is highly developed and both sexes are involved in raising the young. All ''Steatocranus'' species are secretive cave spawners and form

monogamous Monogamy ( ) is a form of Dyad (sociology), dyadic Intimate relationship, relationship in which an individual has only one Significant other, partner during their lifetime. Alternately, only one partner at any one time (Monogamy#Serial monogamy, ...

pairs for breeding. The female is more actively involved in fry raising, while the male is primarily concerned with territorial defence.

Species

There are currently ten recognized species in this genus, but ''S. irvinei'' belongs elsewhere; in 2019 it was proposed to move it to its own genus, ''Paragobiocichla''. * '' Steatocranus bleheri'' M. K. Meyer, 1993 * ''

Steatocranus casuarius ''Steatocranus'' is a genus of small rheophilic cichlids mostly native to the Congo River Basin in DR Congo/Congo Brazzaville, although one species, '' S. irvinei'', is restricted to the Volta River in Ghana and Burkino Faso, and it belongs in a ...

Poll Poll, polled, or polling may refer to: Figurative head counts * Poll, a formal election ** Election verification exit poll, a survey taken to verify election counts ** Polling, voting to make decisions or determine opinions ** Polling places o ...

, 1939 (Lionhead cichlid) * '' Steatocranus gibbiceps''

Boulenger Boulenger is a surname. Notable people with the surname include: * Benjamin Boulenger (born 1990), French footballer * Edward George Boulenger (1888–1946), British zoologist, director of aquarium at London Zoo * George Albert Boulenger (1858–1 ...

, 1899 * ''

Steatocranus glaber ''Steatocranus'' is a genus of small rheophilic cichlids mostly native to the Congo River Basin in DR Congo/Congo Brazzaville, although one species, '' S. irvinei'', is restricted to the Volta River in Ghana and Burkino Faso, and it belongs in a ...

'' T. R. Roberts & D. J. Stewart, 1976 * ''

Steatocranus irvinei ''Steatocranus'' is a genus of small rheophilic cichlids mostly native to the Congo River Basin in DR Congo/Congo Brazzaville, although one species, '' S. irvinei'', is restricted to the Volta River in Ghana and Burkino Faso, and it belongs in a ...

'' ( Trewavas, 1943) * ''

Steatocranus masalamasoso ''Steatocranus'' is a genus of small rheophilic cichlids mostly native to the Congo River Basin in DR Congo/Congo Brazzaville, although one species, '' S. irvinei'', is restricted to the Volta River in Ghana and Burkino Faso, and it belongs in a ...

'' Zamba ''et al.'', 2022 * ''

Steatocranus mpozoensis ''Steatocranus'' is a genus of small rheophilic cichlids mostly native to the Congo River Basin in DR Congo/Congo Brazzaville, although one species, '' S. irvinei'', is restricted to the Volta River in Ghana and Burkino Faso, and it belongs in a ...

'' T. R. Roberts & D. J. Stewart, 1976 * ''

Steatocranus rouxi ''Steatocranus'' is a genus of small rheophilic cichlids mostly native to the Congo River Basin in DR Congo/Congo Brazzaville, although one species, '' S. irvinei'', is restricted to the Volta River in Ghana and Burkino Faso, and it belongs in a ...

'' ( Pellegrin, 1928) * '' Steatocranus tinanti'' (

, 1939) * '' Steatocranus ubanguiensis'' T. R. Roberts & D. J. Stewart, 1976

References

{{Taxonbar, from=Q135247 Pseudocrenilabrinae Fishkeeping Cichlid genera Taxa named by George Albert Boulenger