Ceropegia distincta (Asclepiadaceae) and Some Related Species in Tropical East and Southern Africa

Abstract

C. distincta was described by N. E. Brown in 1895 from a single collection made by Sir John Kirk in Zanzibar. In his account of the Asclepiadaceae in the Flora of Tropical Africa some eight years later, and since no further material had become available, Brown made the comment that the lobes of the flower were only seen in a bud and that the corona was damaged or incomplete. Werdermann (1939), when studying the East African species of Ceropegia, reported on the lack of a mature flower in the type specimen of this species and commented sceptically on the tubular coalescence of the corolla-lobes in a mature flower. He suspected that, while the narrow, stalk-like part of the corolla-lobes lie close together in the bud, they separate when the flower opens and only remain joined at the tips. He deduced this from a study of a specimen which he described as C. cyrtoidea, a new species closely related to C. distincta (see p. 000). The type specimen of C. distincta in the Kew Herbarium consists of two portions of stem with several detached leaves. The shorter portion of stem, which in its flattened and dried condition is up to 4 mm thick, bears a peduncle 25 mm long with one flower bud attached. The bud is curved, has an overall length of 20 mm and shows the characteristically abruptlynarrowed, stalk-like corolla-lobes with their expanded apices. The comparatively large calyx-lobes, 10-11 mm long, are evident both in the bud and on a separate inflorescence. This latter inflorescence consists of a peduncle 36 mm long bearing a single pedicel 14 mm long with a calyx but no corolla. Mutilated remnants of a corolla and a corona are present but in such a poor condition that no characters at all can usefully be distinguished. Amongst material examined in the Paris Herbarium, Werdermann discovered an undetermined specimen of Ceropegia from Zanzibar, Sacleux 326, which he identified as C. distincta and which is amply described. Huber (1958), in his revision of the genus, confirmed the identity of Sacleux 326 with Kirk's original collection and added two further Zanzibar collections: Vaughan 1177 and 1509 both in the Kew Herbarium. The first of these collections