[2][3] The genus is native to tropical and subtropical regions of Africa, Asia, South America, and Australia.

[7] The flowers are held in a herbaceous bract that is many nerved and has two to six clear ribs.

[7] The ovary is oblong and beaked with strongly developed placentas dividing it into six chambers that contain many ovules.

[5][6]They are mostly found growing in lakes, slow flowing creeks and rivers.

[6] Global cooling, the development of the East Asian monsoon climate and tectonic movement likely aided diversification in China.

The movement of the Yunnan-Guizhou Plateau Pin the liocenehas been suggested to explain the high endemism of Chinese species of Ottelia.