80. Rubovietnamia Tirvengadum, Biogeographica (Paris). 74(4): 166. 1998.
越南茜属 yue nan qian shu
Authors: Tao Chen & Charlotte M. Taylor
Shrubs, unarmed, sometimes with some internodes markedly shortened. Raphides absent. Leaves opposite, sometimes appearing ternate due to reduced internode and marked anisophylly grouping 2 leaves at one node plus an apparently solitary leaf at another node, usually with domatia, at apex sometimes aristate; stipules caducous to late deciduous, shortly united around stem, triangular, inside (i.e., adaxially) pubescent, sometimes aristate. Inflorescences terminal and/or pseudoaxillary, cymose and 2-8-flowered or sometimes reduced to 1 flower, pedunculate, bracteate with bracts often stipuliform. Flowers pedunculate or pedicellate, bisexual, monomorphic. Calyx limb deeply 5-lobed; lobes sometimes imbricate in bud. Corolla white turning yellow with age, salverform to funnelform, inside glabrous except with a pilosulous ring near base; lobes 5, convolute in bud. Stamens 5, inserted near corolla throat, partially exserted; filaments reduced; anthers dorsifixed near base, becoming twisted with age, shortly sagittate at base, with connective prolonged in an apical triangular appendage. Ovary 1-celled, ovules 2-4 on parietal placentas; stigmas 2, spatulate, partially exserted. Fruit baccate, fleshy to leathery, subglobose, smooth, mature color unknown, with calyx limb tardily deciduous; seeds few to several, medium-sized, ovoid to subglobose, smooth; endosperm abundant; embryo minute, basal, nail-shaped; radicle slightly longer than cotyledons; cotyledons suborbicular.
Two species: China, Vietnam; two species (one endemic) in China.
The protologue figure is labeled "Vidalasia aristata," but this species was treated in the text in Rubovietnamia; Vidalasia Tirvengadum was also described in this same article, and presumably R. aristata was to be included in that genus initially. Vidalasia has several-flowered compound cymes, erose-setose stipules and bracts, numerous ovules and seeds, and probably may be expected in China also.
