''Paratilapia'' is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

cichlid Cichlids () are a large, diverse, and widespread family of percomorph fish in the family Cichlidae, order Cichliformes. At least 1,760 species have been scientifically described, making it one of the largest vertebrate families, with on ...

s generally restricted to

Madagascar Madagascar, officially the Republic of Madagascar, is an island country that includes the island of Madagascar and numerous smaller peripheral islands. Lying off the southeastern coast of Africa, it is the world's List of islands by area, f ...

. These are large, dark cichlids densely covered in light spots. An additional very poorly known species from the

Congo River The Congo River, formerly also known as the Zaire River, is the second-longest river in Africa, shorter only than the Nile, as well as the third-largest river in the world list of rivers by discharge, by discharge volume, following the Amazon Ri ...

basin in mainland Africa is sometimes also placed in the genus, but this is highly questionable and arguably it is better placed in the "

wastebasket genus Wastebasket taxon (also called a wastebin taxon, dustbin taxon or catch-all taxon) is a term used by some taxonomists to refer to a taxon that has the purpose of classifying organisms that do not fit anywhere else. They are typically defined by e ...

" ''

Haplochromis ''Haplochromis'' is a ray-finned fish genus in the family Cichlidae. It has been used as the default " wastebin taxon" for Pseudocrenilabrinae cichlids of the East African Rift, and as such became the "largest" fish "genus". Many of these cichl ...

'' for the time being.Greenwood (1979). ''Towards a phyletic classification of the 'genus' Haplochromis (Pisces, Cichlidae) and related taxa.'' Bulletin of the British Museum (Natural History) Zoology 35(4): 265-322

Taxonomy

Phylogenetic In biology, phylogenetics () is the study of the evolutionary history of life using observable characteristics of organisms (or genes), which is known as phylogenetic inference. It infers the relationship among organisms based on empirical dat ...

analyses of

DNA sequence A nucleic acid sequence is a succession of bases within the nucleotides forming alleles within a DNA (using GACT) or RNA (GACU) molecule. This succession is denoted by a series of a set of five different letters that indicate the order of the nu ...

and morphological data have hitherto been unable to resolve the relationships of the genus to satisfaction. For example, sequence data from

mtDNA Mitochondrial DNA (mtDNA and mDNA) is the DNA located in the mitochondria organelles in a eukaryotic cell that converts chemical energy from food into adenosine triphosphate (ATP). Mitochondrial DNA is a small portion of the DNA contained in ...

16S rRNA 16S ribosomal RNA (or 16Svedberg, S rRNA) is the RNA component of the 30S subunit of a prokaryotic ribosome (SSU rRNA). It binds to the Shine-Dalgarno sequence and provides most of the SSU structure. The genes coding for it are referred to as ...

and COI disagree regarding its placement, (2004): Molecular phylogeny and biogeography of the Malagasy and South Asian cichlids (Teleostei: Perciformes: Cichlidae). ''Molecular Phylogenetics and Evolution'' 30(3): 599–614. (HTML abstract) and the standard hypothesis among cichlids - that this is due to hybridization effects - can obviously not apply here as both genes are mitochondrial and affected by

hybrid introgression Introgression, also known as introgressive hybridization, in genetics is the transfer of genetic material from one species into the gene pool of another by the repeated backcrossing of an interspecific hybrid with one of its parent species. Introg ...

in the same way. In any case, ''Paratilapia'' tends to occupy a position between African subfamilies such as the

Ptychochrominae The Ptychochrominae are a subfamily in the cichlid family of fish. It includes about 14 species. They are restricted to lakes and rivers in Madagascar, and the majority are threatened. Most cichlid genera native to Madagascar are included in thi ...

and the Indo-Malagasy

clade In biology, a clade (), also known as a Monophyly, monophyletic group or natural group, is a group of organisms that is composed of a common ancestor and all of its descendants. Clades are the fundamental unit of cladistics, a modern approach t ...

comprising the

Etroplinae Etroplinae is a subfamily in the cichlid family of fishes. The subfamily includes 3 genera (and about 16 species) : '' Etroplus'' and '' Pseudetroplus'', which are the only cichlids native to India and Sri Lanka, and '' Paretroplus'' from Madagas ...

and

in most analyses, and this may well be correct. If so, its ancestors must have separated from those of all other living cichlids in the

Mesozoic The Mesozoic Era is the Era (geology), era of Earth's Geologic time scale, geological history, lasting from about , comprising the Triassic, Jurassic and Cretaceous Period (geology), Periods. It is characterized by the dominance of archosaurian r ...

. They most probably were already a distinct lineage by the

Turonian The Turonian is, in the International Commission on Stratigraphy, ICS' geologic timescale, the second age (geology), age in the Late Cretaceous epoch (geology), Epoch, or a stage (stratigraphy), stage in the Upper Cretaceous series (stratigraphy), ...

(about 90 million years ago), as the Indo-Malagasy clade must have originated before the split of Madagascar from the

Indian Plate The Indian plate (or India plate) is or was a minor tectonic plate straddling the equator in the Eastern Hemisphere. Originally a part of the ancient continent of Gondwana, the Indian plate broke away from the other fragments of Gondwana an ...

, which commenced then and was finished by the end of the

Cretaceous The Cretaceous ( ) is a geological period that lasted from about 143.1 to 66 mya (unit), million years ago (Mya). It is the third and final period of the Mesozoic Era (geology), Era, as well as the longest. At around 77.1 million years, it is the ...

. Consequently, they would have to be classified as a

subfamily In biological classification, a subfamily (Latin: ', plural ') is an auxiliary (intermediate) taxonomic rank, next below family but more inclusive than genus. Standard nomenclature rules end botanical subfamily names with "-oideae", and zo ...

of their own, the Paratilapiinae. While currently included in this genus, ''P. toddi'' probably does not belong here. Correct placement is uncertain.

Species

The recognized species in this genus are: * ''

Paratilapia polleni ''Paratilapia polleni'' is a medium-sized cichlid endemism, endemic to Madagascar. It is also a popular fish for display at public aquarium, aquaria. It is sometimes referred to by the common names starry-night cichlid, polleni cichlid, and bla ...

Bleeker Bleeker is a Dutch occupational surname. Bleeker is an old spelling of ''(linnen)bleker'' ("linen bleacher").Paratilapia toddi ''Paratilapia toddi'' is a small species of fish in the family Cichlidae. It is only known from the type locality of Lusambo, Kasai River The Kasai River (, ; called Cassai in Angola) is a left bank tributary of the Congo River, located in ...

'' Boulenger, 1905 – unlikely to belong in this genus

References

{{Taxonbar, from=Q898772 Cichlid fish of Africa Freshwater fish genera Cichlid genera Taxa named by Pieter Bleeker Ptychochrominae