Osphronemus

The elephant ear gourami, Osphronemus exodon, is a large gourami from Thailand, Laos and Cambodia. Its greatly enlarged teeth, with an extra set in concentric bands on the outer lips, stay visible when the mouth is closed and are used to pick fruit from overhanging branches. Reaching 60 cm, it inhabits still or slow-moving areas of large rivers and enters flooded forest in the rainy season.

The giant gourami, Osphronemus goramy, is a large gourami from Borneo, Java, Sumatra, Thailand, Indo-china and the Malay Peninsula. Reaching 70 cm and living for over 20 years, it is often sold as a juvenile with no information on its adult size. It is cultured for food on a large scale, a golden variety exists in aquaria, and dyed fish are produced by injecting colour under the skin.

The giant red tail gourami, Osphronemus laticlavius, is a large gourami from Indonesia and Malaysia, described to science in the early 1990s. Adults develop bright red fin edges with filamentous extensions and a body colour between blue-green and almost black. It reaches 50 cm and probably inhabits slow-moving rivers and other sluggish or stagnant water.