A revision of Lebeckia sect. Lebeckia: The L. pauciflora and L. wrightii groups (Fabaceae, Crotalarieae)

All 14 species of the type section of the genus Lebeckia Thunb. are endemic to the Cape Floristic Region and are easily recognized by their phyllodinous, acicular (needle-shaped) leaves. Ten of the 14 species, comprising the L. sepiaria and L. plukenetiana groups, have already been revised. The last two groups are formally treated in this paper: 1. the L. pauciflora group (two virgate perennials with terete to semi-terete, stipitate fruits) and 2. the L. wrightii group (two trailing fireweeds with flat, sessile fruits). One of these, L. uniflora B-E.van Wyk and M.M.le Roux sp. nov., is here described as new. The new species was previously confused with L. wrightii (Harv.) Bolus but differs in the single-flowered inflorescences, larger flowers and black seeds. The nomenclature, typification, morphological and diagnostic characters are presented as well as distribution maps. A comprehensive key to all 14 species of section Lebeckia is provided.