Spermacoce or false buttonweed is a genus of flowering plants in the family Rubiaceae. It comprises about 275 species found throughout the tropics and subtropics. Its highest diversity is found in the Americas, followed by Africa, Australia and Asia. It can be used for the treatment of eczema by rubbing the leaves on the affected part.
Description
The species are herbs or small shrubs with small- to medium-sized, four-lobed flowers arranged in capitate inflorescences. Some have a brightly coloured calyx and are eye-catching, particularly the Australian species. The corolla is variable in colour, often white, but also all shades of blue, pink and maroon. The fruit is usually a two-seeded capsule, sometimes a schizocarp or nut.
Selected species
Spermacoce is a highly diverse genus with over 290 species in many tropical and subtropical places around the globe. North American species include:
Spermacoce alata Aubl. - West Indies, most of Latin America; naturalized in Africa, India, China, Southeast Asia, Australia, Melanesia
Spermacoce brachysepala (Urb.) Alain in H.A.Liogier & L.F.Martorell - West Indian false buttonweed - Puerto Rico, Haiti, Dominican Republic
Spermacoce capitata Ruiz & Pav. - baldhead false buttonweed - Central and South America from Belize to Argentina
Spermacoce confusa Rendle - river false buttonweed - Florida, West Indies, Latin America from Mexico to Argentina
Spermacoce densiflora (DC.) Alain - bouquet false buttonweed - Florida, West Indies, Latin America from Mexico to Argentina
Spermacoce eryngioides (Cham. & Schltdl.) Kuntze - whorled-leaf false buttonweed - West Indies including Puerto Rico; southeastern South America from Bolivia and Brazil to Argentina
Spermacoce exilis (L.O. Williams) C. Adams - Pacific false buttonweed - Latin America from Mexico to Argentina, plus West Indies; naturalized in Africa, China, India, southeast Asia and some tropical oceanic islands
Spermacoce glabra Michx. - smooth false buttonweed - southern and...
