''Betta cracens'' is a species of

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 ...

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 else ...

to the island of Sumatra in

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 ...

. It is an inhabitant of freshwater swamp forest. This species grows to a length of , typically inhabits blackwaters that have very soft and very acidic water and is a

bubble nest Bubble nests, also called foam nests, are created by some fish and frog species as floating masses of bubbles blown with an oral secretion, saliva bubbles, and occasionally aquatic plants. Fish that build and guard bubble nests are known as aph ...

brooder. The Latin term ''cracens'' means "slender" or "elegant" and is so named because of the fish's slender body. It was first described in 1996 by Heok Hui Tan and Peter K. L. Ng in ''

The Raffles Bulletin of Zoology ''The Raffles Bulletin of Zoology'' is a peer-reviewed open-access scientific journal published by the Lee Kong Chian Natural History Museum at the National University of Singapore. It covers the taxonomy, ecology, and conservation of Southeast ...

''. The ''Betta Cracens'' have a Labyrinth Organ, a morpho‐physiological adaptation that allows them to respirate in air. The Labyrinth Organ is a folded suprabranchial accessory breathing organ and a defining characteristic of fish in the suborder Anabantoidei. It is formed by vascularized expansion of the epibranchial bone of the first gill arch. This adaptation allows these fish to thrive in their harsh habitats.

References

cracens Taxa named by Heok Hui Tan Taxa named by Peter Kee Lin Ng Fish described in 1996 {{Anabantiformes-stub