 In Asia, they are found throughout East, Southeast, and South Asia, especially but not exclusively in the warm, slow-flowing, low-oxygen waters.In Africa, significantly smaller numbers of labyrinth fish can be found in the southern half of the continent, with concentrations in the rainforest waters.The characteristics of the fish habitats are indicators of the size of the labyrinth organ, as the organ size is negatively correlated with the level of oxygen in the waters.