Summary. The genus Tylophoropsis, hitherto understood to comprise two species, T heterophyllum and T. yemenensis, is reconsidered. A new East African species, T. erubescens Liede & Meve, is described. The two previously recognized species are combined into one variable species, T. heterophyllum. The affinities of Tylophora and Tylophoropsis are discussed. During the Nyika Plateau excursion of the 1991 AETFAT meeting, an Asclepiadaceae with relatively small but very attractive dark red flowers was found in a remnant of Juniperus forest. None of the experts present could recognize it, and the plant remained one of the unsolved riddles of the conference. When we later examined the flowers more closely, we found that they contained pendulous pollinia. The plant thus belongs to the tribe Asclepiadeae, which one of us (SL) has been studying for several years. Trying to clarify the plant's position within the Asclepiadeae, we found that it matched some specimens in K and MO which had been placed under 'Tylophora indet.' in the Marsdenieae. With pendulous pollinia, clear latex, few flowers per inflorescence and a corona of purely staminal parts, however, this new species clearly is a member of the small, poorly understood genus Tylophoropsis R.Br. During our studies, we realized that the two hitherto recognized species, T. heterophylla (Vatke) N.E.Br. and T. yemenensis (Deflers) N.E.Br., represent a single, but variable and probably clinal species, T. heterophylla. Tylophoropsis heterophylla (Vatke) N.E.Br., Gard. Chron. ser. 3, 16: 244 (1894); Oliv., Hooker's Ic. P1. 24: t.2373 (1895). Vincetoxicum heterophyllum Vatke, Linnaea 40: 212 (1876). Type: Schimper 471