The Malabar swamp eel (''Rakthamichthys indicus'') (not to be confused with ''

Ophichthys fossorius ''Ophichthys'' is a genus of swamp eels native to South Asia. They live in freshwater or subterranean habitats, and some have a fossorial lifestyle. Taxonomy All species in this genus were formerly classified in ''Monopterus'', but a 2020 stu ...

'', also known as the Malabar swampeel) is a species of troglobitic swamp eel

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsew ...

to subterranean springs in

Kottayam Kottayam () is a municipal town in the Indian state of Kerala. Flanked by the Western Ghats on the east and the Vembanad Lake and paddy fields of Kuttanad on the west. It is the district headquarters of Kottayam district, located in south-we ...

in the

Indian Indian or Indians may refer to: Peoples South Asia * Indian people, people of Indian nationality, or people who have an Indian ancestor ** Non-resident Indian, a citizen of India who has temporarily emigrated to another country * South Asia ...

state of

Kerala Kerala ( ; ) is a state on the Malabar Coast of India. It was formed on 1 November 1956, following the passage of the States Reorganisation Act, by combining Malayalam-speaking regions of the erstwhile regions of Cochin, Malabar, South ...

Taxonomy

It was originally described as ''

Monopterus ''Monopterus'' is a genus of swamp eels native to Asia. They live in various freshwater habitats and some have a fossorial lifestyle.Britz, R., Doherty-Bone, T.M., Kouete, M.T., Sykes, D. & Gower, D.J. (2016)''Monopterus luticolus'', a new specie ...

indicus'' by K. C. Eapen in 1963, but another fish with the same scientific name, the

Bombay swamp eel The Bombay swamp eel (''Ophichthys indicus''), also known as the paytop in Marathi, is a species of fish in the family Synbranchidae. It is endemic to the state of Maharashtra in India. Taxonomy It was at first classified in the genus ''Amphip ...

(formerly also ''Monopterus indicus'', now ''Ophichthys indicus'') had already been described 2 years prior. Due to this causing a

homonym In linguistics, homonyms are words which are homographs (words that share the same spelling, regardless of pronunciation), or homophones (equivocal words, that share the same pronunciation, regardless of spelling), or both. Using this definition, ...

the species had to be renamed but due to the lack of specimens, it was tentatively referred to as ''Monopterus'' "''indicus''". It was later redescribed as ''Monopterus eapeni'' in 1991. A 2020 study found ''M. eapeni'' to form a clade with two other troglobitic species from the Western Ghats and one fossorial species from Northeast India, leading it to be reclassified in the new genus ''Rakthamichthys'', lifting the homonym problem and allowing the original

specific epithet In taxonomy, binomial nomenclature ("two-term naming system"), also called nomenclature ("two-name naming system") or binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, bot ...

of ''indicus'' to be revived.

Status

Due to the subterranean nature of this species, very little information is known about it, and it had not been collected from the type locality since 1979 till 2021 March when it was found while cleaning a well at Panthalam, Kerala. Due to this, it is classified as

Data Deficient A data deficient (DD) species is one which has been categorized by the International Union for Conservation of Nature (IUCN) as offering insufficient information for a proper assessment of conservation status to be made. This does not necessaril ...

on the

IUCN Red List The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is the world's most comprehensive inventory of the global conservation status of biol ...

References

Rakthamichthys Cave fish Freshwater fish of India Taxa named by K.C. Eapen Fish described in 1963 Endemic fauna of the Western Ghats Fauna of Kerala {{synbranchiformes-stub