Differt a speciebus ceteris generis Riveae habitu erecto et praesertim speciei proximae Riveae ornatae sepalis exterioribus margine piano non involute et staminibus circa medium tubi corollae insertis vel paullo inferius. Indo-China. Laos, prov. Vientiane, vicinity of Vientiane, c. 200 m alt., in open Dipterocarpaceae monsoon forest, on sandy lateritic soil; erect shrub, 1.50 m high; flowers white with greenish midpetaline bands, fl. Aug. 20, 1953 (rain-season); vernacular name: phi yik; Vidal 2350 (TL, type; fragments in L). A fruiting specimen from the same locality was collected Oct. 8, 1952; Vidal 1120 (TL; fragments in L).