{{Short description|Species of fish}} {{Speciesbox | image = Betta pi.jpg | image_caption = | status = EN | status_system = IUCN3.1 | status_ref = <ref name="iucn status 20 November 2021">{{cite iucn |author=Low, B.W. |date=2019 |title=''Betta pi'' |volume=2019 |article-number=e.T91310460A91310464 |doi=10.2305/IUCN.UK.2019-2.RLTS.T91310460A91310464.en |access-date=20 November 2021}}</ref> | taxon = Betta pi | authority = H. H. Tan, 1998 | synonyms = }}
'''''Betta pi''''' is a species of gourami belonging to the genus ''Betta''. It is found in the Pru Toe-Daeng peat swamps in Narathiwat Province in Southern Thailand, but its range also extends into northern Peninsular Malaysia, most notably the states of Kelantan and Terengganu.<ref name=":0">{{Cite web |title=Betta pi - Seriously Fish |url=https://www.seriouslyfish.com/species/betta-pi/ |website=Seriously Fish}}</ref> It is primarily found in well-shaded peat forest blackwater swamps and creeks where the pH can be as low as 3.0 or 4.0.<ref name=":0" /> It is benthopelagic. It can grow to a maximum length of {{convert|9.0|cm|in|abbr=on}}.<ref>{{Cite web|title=Betta pi|url=https://www.fishbase.de/summary/Betta-pi.html|access-date=2021-09-07|website=www.fishbase.de}}</ref> It is a fish of mild importance in the aquarium industry. Its diet consists of aquatic invertebrates in the wild, but will also eat frozen, live and dried foods such as larva of Chironomidae (also known as bloodworms), ''Daphnia,'' and brine shrimp in aquariums.<ref name=":0" />
== Anatomy and behavior ==
=== Anatomy === ''Betta pi'' has a body, coloration, and anatomy typical of the ''B.wasseri'' complex of closely related fish. It is mostly clay yellow, with iridescent gold scales in adult males, and black throat markings, which in ''Betta pi'' resemble the Greek letter pi, hence the specific name. It is also, like all fish of the ''Betta'' genus, a facultative air-breathing fish, because of its labyrinth organ.<ref name=":0" />
=== Behavior === ''Betta pi'' is a relatively less aggressive fish than most of the others in the genus ''Betta.'' However, it is still not recommended that it is put in a community aquarium (mostly because of maintenance requirements).<ref name=":0" />
== Sexual dimorphism == ''Betta pi'' displays mild sexual dimorphism, with males growing larger, developing more extended fins, and also having a broader head than females.<ref name=":0" />
== Reproduction and development == Being a mouthbrooder, ''Betta pi'' has a breeding process which is very typical of mouthbrooding fish of the ''Betta'' genus. Following a protracted courtship, eggs and milt are released during a stage where the male is wrapped around the female. This is typical of gouramis. The male might have to wrap around the female several times before spawning happens. Then, fertilised eggs are caught on the anal fin of the male, then picked up in the mouth of the female before being spat out into the water for the male to catch. Once the male has all the eggs in his mouth the process is repeated until the female is spent of eggs, a process which can take some time.<ref name=":0" />A brooding male may swallow or release the eggs prematurely if stressed or inexperienced. The incubation period is usually 10-28 days, after which the male will begin to release free-swimming fry. The adults tend not to eat the fry, and some breeders have reported them to develop at a faster rate when left with the parents. The fry are large enough to accept foods such as microworm and brine shrimp immediately, though there exist reports of young ''Betta'' developing health issues if it eats excessive amounts of the latter. In the aquarium, water changes should be small and regular rather than large and intermittent.<ref name=":0" />
As a result of the males' mouthbrooding capabilities, ''Betta pi'' exhibits male-only parental behavior. After the female releases the eggs, she does not play a role in caring for the offspring. Rather, the male guards the eggs until they have developed.<ref>{{Cite journal |last=Greene |first=Susan M. |last2=Szalda-Petree |first2=Allen D. |date=2022-01-01 |title=Fins of Fury or Fainéant: Fluoxetine impacts the aggressive behavior of fighting fish (Betta splendens) |url=https://linkinghub.elsevier.com/retrieve/pii/S037663572100228X |journal=Behavioural Processes |volume=194 |article-number=104544 |doi=10.1016/j.beproc.2021.104544 |issn=0376-6357|url-access=subscription }}</ref><ref>{{Cite journal |last=Rüber |first=Lukas |last2=Britz |first2=Ralf |last3=Tan |first3=Heok Hui |last4=Ng |first4=Peter K. L. |last5=Zardoya |first5=Rafael |date=2004-04-01 |title=EVOLUTION OF MOUTHBROODING AND LIFE‐HISTORY CORRELATES IN THE FIGHTING FISH GENUS BETTA |url=https://academic.oup.com/evolut/article-abstract/58/4/799/6756785?redirectedFrom=fulltext |journal=Evolution |volume=58 |issue=4 |pages=799–813 |doi=10.1111/j.0014-3820.2004.tb00413.x |issn=0014-3820}}</ref>
== In the aquarium == ''Betta pi'' is of mild importance in the aquarium trade. It is not recommended that it be housed into a community aquarium, not because of its aggressive nature typical of gouramis, but because of its very specific requirements. The water conditions recommendable for ''Betta pi'' include 4.0-6.5 in pH, and 18-90 ppm in GH. It requires acidic water, negligible carbonate hardness and very soft water. It should be maintained in a fully decorated aquarium, and driftwood roots and driftwood branches should be arranged so that there is some degree of shade added, while clay pots and tubes can be added as hiding spots and shelter. Adding dried leaf litter as a substrate can add even more cover and also starts a microbial colony, and tannins present in the leaves are beneficial for ''Betta pi,'' as it is a fish from blackwater environments. ''Betta pi,'' like other fish of its genus, thrive with dim lighting. Plants that withstand the conditions required by ''Betta pi'' include ''Microsorum, Taxiphyllum,'' and ''Cryptocoryne.'' Floating plants are a beneficial addition to the tank as well. The filter should be a low-flow filter, as ''Betta pi'' is an inhabitant of sluggish water.<ref name=":0" />
== Threats == ''Betta pi'' is threatened with mostly habitat destruction by human activity, with large tracts of forest being cleared for the rubber and palm oil industries.<ref name=":0" />
==References== {{Reflist}} {{Taxonbar|from=Q5761554}}
pi Category:Freshwater fish of Malaysia Category:Taxa named by Heok Hui Tan Category:Fish described in 1998
{{Anabantiformes-stub}} Category:Fish of Thailand