Labyrinth Fishes: Anabantoidei

Physical characteristics: Siamese fighting fish reach a length of about 2 inches (6 centimeters). They have a long tube-shaped body. Some species have large fanlike dorsal, anal, and tail fins. Wild Siamese fighting fish have a bluish body and blue and red fins. There are two shiny marks on the gill cover. Males have larger fins and are more brightly colored than females.

Geographic range: Siamese fighting fish live in Southeast Asia and in areas where they have been accidentally released, such as Florida, in the United States.

Habitat: Siamese fighting fish live in standing water with dense plant life, especially rice paddies and canals. They may dig into the Siamese fighting fish are well known for their aggressive behavior, especially against males in their own species. (©A. N. T./Photo Researchers, Inc. Reproduced by permission.) mud when the water level is low and can survive weeks in a small cocoon-like structure made of mud and probably mucus.

Diet: Siamese fighting fish eat invertebrates such as animal plankton and insect larvae.

Behavior and reproduction: Siamese fighting fish are well known for their aggressive behavior, especially against males in their own species. In small tanks, males fight until one of them dies. A male Siamese fighting fish builds a floating nest of bubbles and aggressively defends the territory around it. He mates with a female under the nest, placing sperm on the eggs as she lays them. The male then takes the eggs one at a time into his mouth and shoves them into the nest. The eggs hatch about thirty-six hours later, and the larvae swim free on the fourth day.

Siamese fighting fish and people: Siamese fighting fish are popular in aquariums.

Conservation status: Siamese fighting fish are not threatened or endangered. ∎