A revision of Centella series Capenses (Apiaceae)

Centella capensis (L.) Domin and related species form a distinct but poorly known group within the genus. The most conspicuous diagnostic feature is the unique inflorescence structure. Each umbel comprises a central umbellule reduced to a single, sessile, functionally female flower and four lateral, functionally male, pedicellate umbellules each reduced to a single flower. The umbel is surrounded by four large, foliaceous bracts. Another unusual character is the habit. Most of the species are annuals or short-lived perennials, while all other species of the genus are perennial shrublets. A taxonomic revision of the four species and three varieties recognized, is presented.