Abstract: In the classification of J. D. Hooker (1873) and of K. Schumann (1891), the genus Prismatomeris Thw. is included in the tribe Morindeae of Rubiaceae. In the modern classifications, e. g. Bremekamp (1966), however, the taxonomic position of the genus is still uncertain. The genus agrees with the tribe Morindeae in the downward radicle, valvate aestivation of the corolla lobes and presence of raphides, but it differs significantly from the latter in the free flowers, bilocular ovary and the peltate ovule attached to the upper half of septum. Therefore, it would be more suitable that the genus is separated from the tribe Morindeae Miq., and is raised to the rank of tribe, placed in the subfamily Rubioideae based on Bremekamp’s delimitation. In the present paper ten character pairs of the genus and the notes on their taxonomic value are presented and two following species are recognized: 1. P. tetrandra (Roxb.) K. Schum. is found in northern India. Its subspecies, which is distributed in Yunnan of China and in Thailand, was previously called P. tetrandra (Roxb.) K. Schumann, and is now revised as P. tetrandra (Roxb.) K. Schum. subsp. multiflora (Ridley) Y. Z. Ruan. 2. P. connata Y.Z. Ruan is described as a new species, that has been treated as P. tetrandra (Roxb.) K. Schum. by previous auth rs. It is native to the subtropic region of South China. Its tropical new subspecies, P. connata. Y. Z. Ruan subsp. hainanensis Y. Z. Ruan, is found on Hainan Island.

Key words: Prismatomeris, P.tetrandra subsp.multiflora, P.connata, P.connata subsp.hainanensis, Systematic position