Aneilema is a genus of approximately 60 species of monocotyledonous flowering herbs in the family Commelinaceae (order Commelinales), making it the third largest genus in that family worldwide, surpassed only by Commelina and Tradescantia. The genus belongs to the monocot class Liliopsida and is one of only six genera in Commelinaceae to occur in both the Eastern and Western Hemispheres.
Plants are annual or perennial herbs distinguished from the closely related Commelina primarily by their flowers: blooms are zygomorphic (bilaterally symmetrical) and, unlike Commelina, typically lack a spathe — the folded, boat-shaped modified leaf that encloses the flower stalk — at the time of flowering. Flowering stalks are generally longer than those of Commelina, ranging from as little as 2 cm to over 25 cm in length.
The overwhelming majority of species are native to sub-Saharan Africa, spanning arid to humid tropical zones across eastern, central, southern, and western Africa. A small number extend into Oceania (Queensland, New Guinea, New Caledonia, Vanuatu), and one species, Aneilema brasiliense, occurs in South America.
Distribution
Aneilema is distributed primarily across sub-Saharan Africa, with the greatest diversity in eastern and southern Africa. A handful of species occur in Oceania (Australia, New Guinea, New Caledonia, Vanuatu), one species (Aneilema brasiliense) is native to South America (Brazil, Venezuela), and one reaches the Caribbean and Central America. The genus is notable as one of only six in Commelinaceae found in both the Eastern and Western Hemispheres.
Taxonomy Notes
Aneilema is placed in the family Commelinaceae, order Commelinales, within the monocots (class Liliopsida). It is most closely allied to Commelina, from which it differs primarily in the general absence of a spathe subtending the inflorescence. With approximately 60 accepted species, it ranks as the third largest genus in Commelinaceae after Commelina and Tradescantia.
