Betta fish can breathe out of water…if they need to!
The anabantoids are also known as labyrinth fishes, which, unlike most other fishes, often do not rely primarily on the gills for respiration. The gills of labyrinth fishes are relatively small and primarily excrete the waste products ammonia and carbon dioxide. In fact, many labyrinth fishes are obligate air breathers, meaning they must breathe at the surface to survive. Other fishes have evolved a number of solutions to allow them to breathe air, including lungs and modifications to their gut and skin. Labyrinth fishes take their name from a specialized air-breathing structure called the labyrinth organ. Labyrinth fishes have paired chambers located above the gills which are extensions of the first gill arch. These chambers contain complex, folded, bony structures covered with respiratory epithelium (the labyrinth organ), allowing them to breathe air.
EVOLUTION, CULTURE, AND CARE FOR BETTA SPLENDENS
Craig Watson, Matthew DiMaggio, Jeffrey Hill, Quenton Tuckett, and Roy Yanong