Aenigmachanna

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Aenigmachanna
Aenigmachanna gollum.jpg
Aenigmachanna gollum
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Clade: Percomorpha
Order: Anabantiformes
Suborder: Channoidei
Family: Aenigmachannidae
Britz, Dahanukar, Anoop, Philip, Clark, Raghavan & Rüber, 2020
Genus: Aenigmachanna
Britz, Anoop, Dahanukar and Raghavan, 2019
Type species
Aenigmachanna gollum
Britz, Anoop, Dahanukar & Raghavan, 2019
Species

2, see text.

Aenigmachanna is a genus of ray-finned fish in the order Ananbantiformes. It is the only genus in the family Aenigmachannidae, or dragon snakeheads. It contains two species, both of which are largely restricted to subterranean habitats in southwestern India, namely in the Western Ghats foothills in the state of Kerala. [1] [2]

Contents

Both of the species in this genus display a unique array of traits that distinguish them from their closest living relatives, the true snakeheads in the family Channidae. These include a much longer and more slender body, numerous scales, a very long anal fin, and a lack of ability to maintain buoyancy. Molecular analyses indicate that they split off from Channidae around 34 or 109 MYA. This may indicate that Aenigmachannidae is a uniquely Gondwanan lineage, and if the higher end of estimations is correct, it may have survived the breakup of the Gondwanan supercontinent around 120 MYA. [1] [3]

They are unique among cavefish for being one of the few cave-dwelling members of the large clade Percomorpha. Despite their habitat, they physically display little troglomorphism aside from a slightly reduced pigmentation, indicating that they either colonized the caves relatively recently or that they are subtroglophiles that mostly live underground, but depend on aboveground habitats for some functions. Due to their restricted habitat and unique nature, both are considered relict species. [3] [4] [5]

Taxonomy

Species

The genus was initially described in early 2019 to serve as a monotypic genus for A. gollum, the first species to be described in the genus. Later in the year, A. mahabali was described as a distinct species, indicating that there were indeed multiple species in the genus. [3] [5]

Related Research Articles

<i>Channa</i> Genus of fishes

Channa is a genus of predatory fish in the family Channidae, commonly known as snakeheads, native to freshwater habitats in Asia. This genus contains about 50 scientifically described species. The genus has a wide natural distribution extending from Iraq in the west, to Indonesia and China in the east, and parts of Siberia in the Far East. A particularly high richness of species exists in Myanmar (Burma) and northeastern India, and many Channa species live nowhere else. In contrast, a few widespread species have been introduced to several regions outside their natural range, where they often become invasive. The large and medium-sized Channa species are among the most common staple food fish in several Asian countries, and they are extensively cultured. Apart from their importance as a food fish, snakeheads are consumed in some regions as a traditional medicine for wound healing and reducing postoperative pain and discomfort, and collected for the international aquarium pet trade.

<i>Parachanna</i> Genus of fishes

Parachanna is a genus of snakeheads native to freshwater habitats in tropical Africa. Three recognized extant (living) species are in this genus, but a phylogenetic study from 2017 indicates that a fourth, currently undescribed species also exists.

<i>Pangio</i> Genus of fishes

Pangio is a genus of small Asian freshwater fish in the true loach family Cobitidae. In earlier taxonomic schemes it was known as Acanthophthalmus. The "kuhli loach" is well-known in the aquarium trade and commonly identified as P. kuhlii, but most individuals actually appear to be P. semicincta.

<span class="mw-page-title-main">Snakehead (fish)</span> Family of fishes

The snakeheads are members of the freshwater perciform fish family Channidae, native to parts of Africa and Asia. These elongated, predatory fish are distinguished by their long dorsal fins, large mouths, and shiny teeth. They breathe air with gills, which allows them to migrate short distances over land. They have suprabranchial organs, which are primitive forms of labyrinth organs, that develop when they grow older. The two extant genera are Channa in Asia and Parachanna in Africa, consisting of more than 50 species.

<span class="mw-page-title-main">Dwarf snakehead</span>

Dwarf snakehead is a term coined by aquarists to describe a group of Channa snakehead fishes growing to about 25 cm (10 in) maximum. They are found in freshwater habitats in South and Southeast Asia, and southern China.

<span class="mw-page-title-main">Forest snakehead</span> Species of fish

The forest snakehead is a species of snakehead, a fish of the family Channidae. Its range includes most of Southeast Asia and parts of southern China. It lives in forest streams and can reach 40 cm (16 in) in length. The forest snakehead is known in Thai language as pla krasong. Khmer language called it កញ្ជនជៃ, Indonesians named it kehung, while in Malaysia, they called it ikan bujuk in Malay Language and in Vietnamese its name is cá lóc dày

<i>Channa gachua</i> Species of fish

Channa gachua, the dwarf snakehead, is a species of fish in the family Channidae. The name "dwarf snakehead" is also used for several other species of small snakeheads. C. gachua is native to freshwater habitats in southern Asia, where it has a wide distribution from Iran to Indonesia. This fish is considered to be a species complex, a group of several closely related taxa with one name. It is likely at least three to four different species, and further research may differentiate them. A few species such as Channa harcourtbutleri have been separated from the complex in recent decades. The easternmost population of C. gachua is often recognized as a separate species C. limbata, while the isolated Sri Lankan population often is recognized as C. kelaartii.

<span class="mw-page-title-main">Channoidei</span> Suborder of fishes

Channoidei is a suborder of fish in the order Anabantiformes. It contains two families: the true snakeheads (Channidae) and the dragon snakeheads (Aenigmachannidae).

<i>Indoreonectes</i> Genus of fishes

Indoreonectes is a genus of stone loaches native to the Western Ghats in India.

<span class="mw-page-title-main">Ceylon snakehead</span> Species of fish

The Ceylon snakehead is a species of snakehead found in freshwater habitats, typically shaded streams, in southwestern Sri Lanka.

<span class="mw-page-title-main">Cavefish</span> Fish adapted to life in caves

Cavefish or cave fish is a generic term for fresh and brackish water fish adapted to life in caves and other underground habitats. Related terms are subterranean fish, troglomorphic fish, troglobitic fish, stygobitic fish, phreatic fish and hypogean fish.

<i>Channa marulius</i> Species of fish

Channa marulius is a large species of snakehead native to South Asia. Populations in Southeast Asia are now regarded as separate species.

<i>Pethia</i> Genus of fishes

Pethia is a genus of small freshwater fish in the family Cyprinidae native to South Asia, East Asia and Mainland Southeast Asia. Some species are commonly seen in the aquarium trade. The name Pethia is derived from the Sinhalese "pethia", a generic word used to describe any of several small species of cyprinid fishes. Most members of this genus were included in Puntius, until it was revised in 2012.

<i>Badis</i> (fish) Genus of fishes

Badis is a genus of freshwater fish in the family Badidae found in South Asia, Southeast Asia and China. These species have a sharp spine on the opercle, soft and spinous parts of the dorsal fin contiguous, three spines in the anal fin, tubed pores in the lateral line, villiform teeth and a rounded caudal fin. In addition, they differ from the related genus Dario by being larger and displaying more involved parental care.

<span class="mw-page-title-main">Rajeev Raghavan</span> Indian conservation biologist

Rajeev Raghavan is a fisheries scientist and aquatic conservation biologist known for his work on the freshwater fishes of the Indian subcontinent. Rajeev is currently an Assistant Professor at the Kerala University of Fisheries and Ocean Studies, Kochi, India, the South Asia Chair of the IUCN’s Freshwater Fish Specialist Group., and the IUCN Freshwater Fish Red List Authority Coordinator for Asia and Oceania.

<span class="mw-page-title-main">Anabantiformes</span> Order of fishes

The Anabantiformes, collectively known as labyrinth fish, are an order of air-breathing freshwater ray-finned fish with two suborders, five families and having at least 207 species. In addition, some authorities expand the order to include the suborder Nandoidei, which includes three families - the Nandidae, Badidae and Pristolepididae - that appear to be closely related to the Anabantiformes. The order, and these three related families, are part of a monophyletic clade which is a sister clade to the Ovalentaria, the other orders in the clade being Synbranchiformes, Carangiformes, Istiophoriformes and Pleuronectiformes. This clade is sometimes referred to as the Carangaria but is left unnamed and unranked in Fishes of the World. This group of fish are found in Asia and Africa, with some species introduced in United States of America.

Channa royi, the Andaman emerald snakehead, is a species of snakehead fish endemic to the Andaman and Nicobar Islands of India. This dwarf snakehead is distinct from other snakehead species due to its differing coloration, number of vertebrae, and teeth, most notably its greenish-gray dorsum. It was only scientifically described in 2018 and its closest relative is the Burmese snakehead, and a review in 2019 argued that the two are synonyms.

Aenigmachanna gollum, the Gollum snakehead, is a species of aquifer-dwelling dragon snakehead fish that is endemic to the Indian state of Kerala.

Aenigmachanna mahabali, the Mahabali snakehead, is a species of troglophilic snakehead fish that is endemic to the Indian state of Kerala.The fish is named after Mahabali, an asura king from Hindu mythology who lived underground and is associated with Onam. It is known from a single specimen recovered from a well over 200 kilometers south of the locality where its closest relative, A. gollum, was found. Alongside A. gollum, it is unique for being the only known cave-dwelling snakehead fish. It can be distinguished from A. gollum due to having fewer dorsal fin rays, vertebrae, and lateral scales, as well as its pectoral fin rays extending beyond the margin of the membrane, forming filaments.

<i>Channa aurolineata</i> Species of fish

Channa aurolineata is a species of Asian snakehead in the family Channidae. It is found natively in most of Myanmar's waterways as well as the Mae Khlong drainage in Thailand. There is also an invasive population found in Southeast Florida, United States. This species was recently split from C. marulius, the bullseye snakehead, and confirmed as a separate species in 2018; and the Florida and Thailand populations were not discovered to be C. aurolineata until even more recently in 2019. Before this, the Thailand population's species was unknown and the Florida ones were assumed to be C. marulius. C. aurolineata was able to be separated as a new species and identified in other areas due to slight differences in color pattern, lateral line scale and fin ray morphology, and DNA structure from the other species in the marulius complex.

References

  1. 1 2 Britz, Ralf; Dahanukar, Neelesh; Anoop, V. K.; Philip, Siby; Clark, Brett; Raghavan, Rajeev; Rüber, Lukas (30 September 2020). "Aenigmachannidae, a new family of snakehead fishes (Teleostei: Channoidei) from subterranean waters of South India". Scientific Reports. 10 (1): 16081. Bibcode:2020NatSR..1016081B. doi: 10.1038/s41598-020-73129-6 . ISSN   2045-2322. PMC   7527459 . PMID   32999397.
  2. Main, Douglas (19 October 2020). "Dragon snakeheads—strange new underground fish—discovered in India". National Geographic . Archived from the original on 20 October 2020.
  3. 1 2 3 Raghavan, Rajeev; Dahanukar, Neelesh; Anoop, V. K.; Britz, Ralf (9 May 2019). "The subterranean Aenigmachanna gollum , a new genus and species of snakehead (Teleostei: Channidae) from Kerala, South India". Zootaxa. 4603 (2): 377–388. doi:10.11646/zootaxa.4603.2.10. ISSN   1175-5334. PMID   31717234. S2CID   164781147.
  4. "New species of subterranean fish named after The Lord of the Rings character". www.nhm.ac.uk. Retrieved 9 May 2019.
  5. 1 2 Ravi, Charan; Basheer, V. S.; Kumar, Rahul G. (17 July 2019). "Aenigmachanna mahabali , a new species of troglophilic snakehead (Pisces: Channidae) from Kerala, India". Zootaxa. 4638 (3): 410–418. doi:10.11646/zootaxa.4638.3.6. ISSN   1175-5334. PMID   31712470. S2CID   203899040.