Subtribal division of Ceropegieae (Apocynaceae­Asclepiadoideae)

Monophyly and sister group relationship of Ceropegieae and Marsdenieae, the two Asclepiadoideae tribes possessing erect pollinia, are confirmed by molecular investigation of non­coding cpDNA markers ( trnT­L and trnL­F spacers, and the trnL intron). In Ceropegieae, the analyzed taxa fall in four subclades. The Heterostemma subclade is sister to other three subclades, of which the Conomitra­Leptadenia­Orthanthera subclade is sister to the Anisotoma­Neoschumannia­Riocreuxia­Sisyranthus subclade and to the large subclade comprising the stem­succulent stapeliads, Brachystelma and Ceropegia . Following these results, subdivision of Ceropegieae into four subtribes, Anisotominae, Heterostemminae, Leptadeniinae and Stapeliinae, is proposed.