The peaceful betta or crescent betta (''Betta imbellis'') is a

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

gourami Gouramis, or gouramies , are a group of freshwater anabantiform fishes that comprise the family Osphronemidae. The fish are native to Asia—from the Indian Subcontinent to Southeast Asia and northeasterly towards Korea. The name "gourami", of ...

native to

Southeast Asia Southeast Asia, also spelled South East Asia and South-East Asia, and also known as Southeastern Asia, South-eastern Asia or SEA, is the geographical United Nations geoscheme for Asia#South-eastern Asia, south-eastern region of Asia, consistin ...

. ''Betta imbellis'' has a pair of suprabranchial chambers that each house a

labyrinth organ The Anabantoidei are a suborder of anabantiform ray-finned freshwater fish distinguished by their possession of a lung-like labyrinth organ, which enables them to breathe air. The fish in the Anabantoidei suborder are known as anabantoids or lab ...

, a complex bony structure lined with thin, highly vascularised

respiratory epithelium Respiratory epithelium, or airway epithelium, is a type of ciliated columnar epithelium found lining most of the respiratory tract as respiratory mucosa, where it serves to moisten and protect the airways. It is not present in the vocal cords o ...

. The labyrinth organ is a morpho‐physiological adaptation that allows the ''B. imbellis'' to extract oxygen from air. This adaptation allows the species to persist in extreme conditions. Males of the species may fight each other especially when in breeding condition.

Description

''Betta imbellis'' grows to a maximum

standard length Fish measurement is the measuring of individual fish and various parts of their anatomies. These data are used in many areas of ichthyology, including taxonomy and fisheries biology. Overall length * Standard length (SL) is the length of a fish m ...

of .

Distribution

''Betta imbellis'' occurs naturally in

Southern Thailand Southern Thailand, Southern Siam or Tambralinga is a southernmost cultural region of Thailand, separated from Central Thailand region by the Kra Isthmus. Geography Southern Thailand is on the Malay Peninsula, with an area of around , bounded ...

Malaysia Malaysia ( ; ) is a country in Southeast Asia. The federation, federal constitutional monarchy consists of States and federal territories of Malaysia, thirteen states and three federal territories, separated by the South China Sea into two r ...

, and

Indonesia Indonesia, officially the Republic of Indonesia, is a country in Southeast Asia and Oceania between the Indian and Pacific oceans. It consists of over 17,000 islands, including Sumatra, Java, Sulawesi, and parts of Borneo and New Guine ...

, although it has been introduced to

Singapore Singapore (), officially the Republic of Singapore, is a sovereign island country and city-state in maritime Southeast Asia. It lies about one degree of latitude () north of the equator, off the southern tip of the Malay Peninsula, borde ...

Habitat

''Betta imbellis'' lives in sluggish bodies of water, including

rice paddies A paddy field is a flooded field of arable land used for growing semiaquatic crops, most notably rice and taro. It originates from the Neolithic rice-farming cultures of the Yangtze River basin in southern China, associated with pre-Aust ...

, swamps, streams and ponds, with a substrate composed of

leaf litter Plant litter (also leaf litter, tree litter, soil litter, litterfall or duff) is dead plant material (such as leaves, bark, needles, twigs, and cladodes) that have fallen to the ground. This detritus or dead organic material and its constituent ...

and mud.

Conservation status

''Betta imbellis'' is listed as

least concern A least-concern species is a species that has been categorized by the International Union for Conservation of Nature (IUCN) as evaluated as not being a focus of species conservation because the specific species is still plentiful in the wild. T ...

by 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 ...

. It is still threatened by pollution and hybridization with released domesticated bettas (

Siamese fighting fish The Siamese fighting fish (''Betta splendens''), commonly known as the betta, is a freshwater fish native to Southeast Asia, namely Cambodia, Laos, Myanmar, Malaysia, Indonesia, Thailand, and Vietnam. It is one of 73 species of the genus ''Bett ...

) and other bettas in the ''B. splendens'' complex.

Diet

In the wild, ''Betta imbellis'' feeds on terrestrial and aquatic

invertebrates Invertebrates are a paraphyletic group of animals that neither possess nor develop a vertebral column (commonly known as a ''backbone'' or ''spine''), derived from the notochord. This is a grouping including all animals apart from the chordate ...

. In captivity, the species is fed live or frozen food like ''

Daphnia ''Daphnia'' is a genus of small planktonic crustaceans, in length. ''Daphnia'' are members of the order Anomopoda, and are one of the several small aquatic crustaceans commonly called water fleas because their saltatory swimming style resembl ...

'', ''

Artemia ''Artemia'' is a genus of aquatic crustaceans also known as brine shrimp. It is the only genus in the family Artemiidae. The first historical record of the existence of ''Artemia'' dates back to the first half of the 10th century AD from Urmia La ...

'' or bloodworms.

Breeding

The more colorful bodies of the males distinguish them from the females, with the males having blue hues in their brownish bodies. Male and female individuals of ''Betta imbellis'' can live together outside of breeding season, as well as getting together for breeding. Males will build a bubble nest before breeding. After mating, the male catches the falling eggs and places them in his bubble nest. In 1–2 days, the eggs hatch and continue to absorb their yolk sack for 2 days. After that, the fry became free to swim. Until then, the male cares for them.

Human use

''Betta imbellis'' is found in the aquarium trade.

References

External links

Betta imbellis care sheet at FishGeeks
Peaceful betta Freshwater fish of Indonesia Freshwater fish of Malaysia Fish of Singapore Fish of Thailand Taxa named by Werner Ladiges Fish described in 1975 {{Anabantiformes-stub