>Wilhelm Tell DCCXLVI: corrected authorities' names' spellings

2021-07-22T14:14:48Z

corrected authorities' names' spellings

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{{Short description|Species of fish}}
{{Use dmy dates|date=August 2019}}
{{Speciesbox
| image = Aenigmachanna gollum.jpg
| genus = Aenigmachanna
| species = gollum
| authority = [[Ralph Britz|Britz]], [[V.K. Anoop|Anoop]], [[Neelesh Dahanukar|Dahanukar]] and [[Rajeev Raghavan|Raghavan]], 2019
| range_map = {{Location map+ | Kerala
| relief = 1
| caption =
| places =
{{Location map~ | Kerala
| label = Oorakam
| background = none
| lat_deg = 11 | lat_min = 3 | lat_dir = N
| lon_deg = 76 | lon_min = 0 | lon_dir = E
}}
}}
| range_map_caption = Type locality of ''A. gollum'' in Oorakam, Kerala
}}

'''''Aenigmachanna gollum''''', the '''Gollum snakehead''', is a species of [[aquifer]]-dwelling [[Aenigmachanna|dragon snakehead fish]] that is [[Endemism|endemic]] to the [[India|Indian]] state of [[Kerala]].<ref name=":0">{{Cite journal|last1=Raghavan|first1=Rajeev|last2=Dahanukar|first2=Neelesh|last3=Anoop|first3=V. K.|last4=Britz|first4=Ralf|date=2019-05-09|title=The subterranean Aenigmachanna gollum , a new genus and species of snakehead (Teleostei: Channidae) from Kerala, South India|url=https://biotaxa.org/Zootaxa/article/view/zootaxa.4603.2.10|journal=Zootaxa|language=en|volume=4603|issue=2|pages=377–388|doi=10.11646/zootaxa.4603.2.10|issn=1175-5334|pmid=31717234}}</ref>

== Description ==
''A. gollum'' has an elongated, [[eel]]-like body coloured mostly [[brown]] and [[beige]]. Its fins are long and [[Transparency and translucency|transparent]], with the [[dorsal fin]] stretching for about three-quarters of its body length, and the [[anal fin]] stretching for more than half its body length. Its pectoral fin is large, while the [[pelvic fin]] is absent. Its tailfin is [[ovoid]]. Several large scales cover the top of the head. It has a reduced [[swim bladder]].<ref name=":0" /><ref name=":2">{{Cite journal|last=Britz|first=Ralf|last2=Dahanukar|first2=Neelesh|last3=Anoop|first3=V. K.|last4=Philip|first4=Siby|last5=Clark|first5=Brett|last6=Raghavan|first6=Rajeev|last7=Rüber|first7=Lukas|date=2020-09-30|title=Aenigmachannidae, a new family of snakehead fishes (Teleostei: Channoidei) from subterranean waters of South India|url=https://www.nature.com/articles/s41598-020-73129-6|journal=Scientific Reports|language=en|volume=10|issue=1|pages=16081|doi=10.1038/s41598-020-73129-6|issn=2045-2322|doi-access=free}}</ref>

Unlike many [[stygofauna]] - which usually have reduced colouring and have poor or no vision - ''A. gollum'' has well-developed pigmentation and normally-sized eyes.<ref name=":0" /><ref name=":3">{{Cite web|date=2020-10-19|title=Dragon snakeheads—strange new underground fish—discovered in India|url=https://www.nationalgeographic.com/animals/article/new-fish-family-dragon-snakeheads-found-india|url-status=live|access-date=2021-05-18|website=National Geograohic|language=en}}</ref>

Due to its reduced swim bladder, ''A. gollum'' cannot remain buoyant in water.<ref name=":0" /> Like other snakehead fishes, it breathes air. It moves by undulating its fins, like an eel.<ref name=":3" />

== Distribution and habitat ==
''A. gollum'' is known only from its type locality, a paddy field in [[Oorakam]], Kerala, in the biodiverse [[Western Ghats]]; one other occurrence was reported in a well 250 km south of the type locality.<ref name=":0" /> Its habitat in subterranean [[Aquifer|aquifers]] is threatened by about six million groundwater [[Well|wells]] in the region, which lower the [[water table]].<ref name=":3" />

==Etymology==
''A. gollum'' is named after the cave-dwelling character [[Gollum]] from [[J. R. R. Tolkien]]'s ''[[The Hobbit]]'' and ''[[The Lord of the Rings]]'' book series, as a reference to both ''A. gollum'' and Gollum being former surface-dwellers that evolved to adapt to the caves they lived in.<ref name=":0" /><ref name=":1">{{Cite web|url=https://www.nhm.ac.uk/discover/news/2019/may/new-species-of-subterranean-fish-named-after-the-lord-of-the-rings-character.html|title=New species of subterranean fish named after The Lord of the Rings character|website=www.nhm.ac.uk|language=en|access-date=2019-05-09}}</ref><ref>{{Cite web|url=https://www.nhm.ac.uk/press-office/press-releases/-precious--newly-discovered-subterranean-fish-named-after-the-lo.html|title='Precious' newly discovered subterranean fish named after The Lord of the Ring's Gollum|website=www.nhm.ac.uk|language=en|access-date=2019-05-09}}</ref> The genus ''Aenigmachanna'' was raised for the first time on discovery of ''A. gollum'', with ''aenigma'' meaning "[[wikt:enigma|enigma]]" in [[Latin]], and ''Channa'' being the generic name of Asian snakehead fishes.<ref name=":0" />

== Taxonomy ==
[[File:Aenigmachanna gollum taxonomy.jpg|left|thumb|283x283px|Cladogram depicting ''A. gollum''<nowiki/>'s relationship with other channids]]
''A. gollum'' was the first discovered species of the genus ''[[Aenigmachanna]].'' The genus was first placed in the true snakehead fish family [[Snakehead (fish)|Channidae]].<ref name=":0" />

''A. gollum'' was placed in a separate genus because of significant physiological and genetic differences between itself and the other genera in Channidae - ''[[Parachanna]]'' and ''[[Channa]]''. ''A. gollum'' has an unusually long dorsal fin, anal fin and [[vertebral column]] compared to ''Parachanna'' and ''Channa'', and also has a more eel-like body. Unlike the other channids, it also lacks pored scales on the [[lateral line]], which normally carry the lateral-line canal, and has more [[Vertebra|vertebrae]] lacking [[Rib|ribs]]. The other channids also have a longer swim bladder.<ref name=":0" /><ref name=":2" /><ref name=":3" />

In 2020, ''Aenigmachanna'' was placed in its own [[Monotypic taxon|monotypic]] family, the Aenigmachannidae, or the dragon snakeheads.<ref name=":2" /><ref name = Fishbase>{{Fishbase|Aenigmachanna|gollum|month=February|year=2021}}</ref>

==Discovery==
''A. gollum'' was discovered as a result of the [[2018 Kerala floods]], when several individuals were washed out of their aquifer habitat and into a [[paddy field]] in Oorakam, where they were found and photographed by a resident of the village, who posted the pictures on social media. The pictures were noticed by [[Rajeev Raghavan]] from the [[Kerala University of Fisheries and Ocean Studies]], who prompted a study into the species. It was described in 2019. It is the eighth species of fish known from the Kerala aquifers, indicating the presence of a large, hidden ecosystem in the hard-to-study habitat.<ref name=":1" />

== See also ==
* [[Gollum (genus)|''Gollum'' (genus)]], another [[taxon]] of fish named after Gollum

== References ==
{{reflist}}

{{Taxonbar|from=Q63676102}}

[[Category:Fish described in 2019]]
[[Category:Aenigmachanna|gollum]]
[[Category:Cave fish]]
[[Category:Fauna of Kerala]]
[[Category:Freshwater fish of India]]
[[Category:Endemic fauna of India]]
[[Category:Taxa named by Ralf Britz]]

Aenigmachanna gollum - Revision history

>Wilhelm Tell DCCXLVI: corrected authorities' names' spellings