Herb or undershrub. Flowers small, in many-flowered verticillasters condensed in terminal and axillary spikes. Stamens ,in 2 pairs, the lower pair slightly longer;
Asia-Temperate:, China South-Central (Yunnan ‒ present) Asia-Tropical:, Thailand (Thailand ‒ present) Burma: present Central Sumatra: present Continental SE. Asia: present E. Java: present Lesser Sunda Is: present
Monotypic, continental SE. Asia (Burma, Thailand to Yunnan); in Malesia: Central Sumatra, E. Java, and Lesser Sunda Is.