Two new Rubiaceae species, Robbrechtia grandifolia and R. milleri from Madagascar are described. Clearly belonging to the tribe Pavetteae, the species possess an unusual combination of characters (sheathing stipules with intrapetiolar lobes, young shoots and inflorescence parts covered with copious colleter exudate, long-tubed flowers with a well-developed calyx, a bilobed stigma and unilocular fruits with a single, deeply ruminate seed) that makes the establishment of a new genus, Robbrechtia, necessary. Detailed descriptions, illustrations and distribution data of the new taxa are given. The characters of the genus are evaluated and compared to those of the other representatives of the tribe Pavetteae.

Communicating Editor: Fred R. Barrie