New species of Drimia (Hyacinthaceae: Urgineoideae) allied to Drimia marginata from Western and Northern Cape, South Africa

Abstract

Plants until now identified as Drimia marginata (Thunb.) Jessop on account of their leathery, oblong to elliptical leaves with thickened, cartilaginous margins and capitate inflorescences of campanulate flowers, are shown to comprise three sets of populations separable on leaf morphology, ecology and distribution. Typical D. marginata produces 1 (2) oblong, apiculate leaves with retrorsely-scabridulous margins and occurs in fine-grained clay soils on the Hantam and Roggeveld Plateaus. Plants from Namaqualand and the Richtersveld. described here as Drimia pulchromarginata J.C.Manning & Goldblatt. occur in sandy or gravelly soils and produce 2 -4 , elliptical to suborbicular, apiculate leaves with an ornate, duplex margin: the dorsal surface bears a submarginal band of dense, velvety trichomes fringing the thickened, colliculate margin. A third series of populations from seasonally moist sandstones at higher altitude on the interior mountains of the West Coast produces2 or 3(4) narrowly oblong, obtuse leaves with a simple, papillate or colliculate margin and are recognized as D. ligulata J.C.Manning & Goldblatt. A fourth taxon with a similar capitate inflorescence of campanulate flowers produces a solitary, subterete or subclavate leaf, elliptical in section. Recorded from scattered localities in the Northern and Western Cape', it is here described as D. vermiformis J.C.Manning & Goldblatt.