Etroplus is a small genus

Genus

In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 of 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...

s with only three species. They are found in southern India

India

India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...

 and Sri Lanka

Sri Lanka

Sri Lanka, officially the Democratic Socialist Republic of Sri Lanka is a country off the southern coast of the Indian subcontinent. Known until 1972 as Ceylon , Sri Lanka is an island surrounded by the Indian Ocean, the Gulf of Mannar and the Palk Strait, and lies in the vicinity of India and the...

, where they are the only native cichlids.

Their closest living relatives are Paretroplus

Paretroplus

Paretroplus is a genus of fishes in the cichlid family, all of which are endemic to lakes and rivers of Madagascar. The vast majority are threatened and restricted to the northwestern part of the island. Only P. polyactis is found in the southern half of Madagascar and only P. polyactis and P....

from Madagascar

Madagascar

The Republic of Madagascar is an island country located in the Indian Ocean off the southeastern coast of Africa...

. These two lineages must have separated during the Mesozoic

Mesozoic

The Mesozoic era is an interval of geological time from about 250 million years ago to about 65 million years ago. It is often referred to as the age of reptiles because reptiles, namely dinosaurs, were the dominant terrestrial and marine vertebrates of the time...

 already, as Madagascar and the Indian Plate had separated by the end of the Cretaceous

Cretaceous

The Cretaceous , derived from the Latin "creta" , usually abbreviated K for its German translation Kreide , is a geologic period and system from circa to million years ago. In the geologic timescale, the Cretaceous follows the Jurassic period and is followed by the Paleogene period of the...

(Sparks 2004).