Betta macrostoma

The spotfin betta or Brunei beauty is a species of labyrinth fish endemic to the island of Borneo. It generally inhabits pools of very slow-moving water along rivers and streams in very shallow waters of 30 cm (12 in) or less. This species grows to a length of 6.7–10 cm (2.6–3.9 in) in the wild, and is occasionally found in the aquarium trade; in captivity this species regularly reaches 10.1 cm in length. It also has a rectangular body.

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