A new genus of stapeliad, Baynesia (Apocynaceae - Asclepiadoideae - Ceropegieae), is described with a single species, B. lophophora Bruyns. This is known from the mountainous area in the northwestern-most corner of Namibia ,where it was relatively plentiful but very local. Its relationships to Caralluma R. Brown and Pseudolithos P. R. 0. Bally are discussed. At present the group of highly succulent plants known as the stapeliads is considered to form a monophyletic group within the Ceropegieae ,and it consists of 25 genera (Bruyns, 2000). The present new species does not fit comfortably into any of these genera, and consequently it is placed in a new genus, Baynesia. Its closest relationships appear to lie with Caralluma and Pseudolithos; the differences between them are discussed in detail.