[Ebook] The New Guide to Aquarium Fish – Anabantids
The anabantids are a large group of fishes found in the tropical waters of Africa and Asia. They are best known for their ability to breathe atmospheric air. The organ that they use for this is known as the labyrinth (hence the common name labyrinth fishes) and is situated on either side of the head in the gill cavity directly above the gills. The fish takes in air from above the water surface and passes it into two chambers, each of which has a rosette-like structure which looks not unlike a sponge. This has a very good supply of blood vessels close to the surface of the structure, and therefore the fish is able to absorb oxygen from the air.