Ornithogalum pendens (Hyacinthaceae), a new cliff-dwelling succulent from the Northern Cape (South Africa)

摘要

Ornithogalum pendens Van Jaarsv. from sheer rock-faces north-west of Springbok in the Northern Cape is described. The bulbous genus Ornithogalum L. (in a narrow sense) consists of 200 species of which about 108 are confined to South Africa and in particular to the Cape Flo-ristic Region (Obermeyer 1978; Manning & Goldblatt 2003). Recent field studies on cliffs associated with dry river val-leys have revealed several members of Ornithogalum new to science (Van Jaarsveld & Van Wyk 1999, 2003; Van Jaarsveld 2003), including a new summer-dormant species. The new species described in the present paper belongs to subgenus Aspasia, a group found mairily in the winter-rainfall, semi-arid regions of Namaqualand. This group is characterised by their leafy, cymbiform bracts and a style as long as or shorter than the ovary (Obermeyer 1978). Or-nithogalum pendens appears to be an obligate cremnophyte and is only known from sheer cliffs along the Skaaprivier in Namaqualand. Plants grow in rock crevices and leaves become pendent with age.