2. Rubovietnamia nonggangensis F. J. Mou & D. X. Zhang, Bot. Stud. (Taipei). 51: 123. 2010.
弄岗越南茜 nong gang yue nan qian
Shrubs or trees, to 3 m tall, without spines; young branches covered with hairs and densely hirsute under stipules. Petiole 0.5-1 cm; leaves thickly papery, obovate, 8-18 × 3-5 cm, densely pubescent on both surfaces, base cuneate, apex acuminate; main and lateral nerves visible adaxially, very prominent abaxially, secondary veins 7-14 pairs; stipules ca. 5 mm, papery, outside coated with thick hairs, terminating with 2 minute interpetiolar limbs. Inflorescences 2-8-flowered cymes, superaxillary on lateral branches, with both bracts and bracteoles triangular, 3-4 mm; pedicels to 25 mm in open flowers. Flowers 5-merous, very fragrant. Calyx tube campanulate, to 8 mm, hispid, widening at apex with enlarged (well-developed) lobes; lobes elliptic-lanceolate, to 10 × 5 mm, imbricate, markedly veined, coated with dense hairs, apiculate, deciduous. Corolla tubular, glossy, fleshy, waxy, cream white at anthesis, turning yellow with age and without spots in tube; tube dilating gradually to throat, to 35 mm, very narrowly tubular in lower part and convex in middle, ca. 5 mm wide at middle, outside hairy, inside largely glabrous except for a zone 1-1.5 cm above base covered with hairs; lobes obovate to lanceolate, to 18 × 5.5 mm, contorted to left in bud stage, pubescent outside, mostly glabrous inside, reflexed at anthesis. Stamens 5, inserted just at corolla throat and between corolla lobes, sessile; anthers linear, to 5 mm, adnate, 1/2 of length exserted ± medifixed, exserted after anthesis. Ovary inferior, with 2 parietal placentas, numerous ovules each in 2 rows on an oblong-elliptic placenta fusing to form a compact mass when mature; style 3.5-4 cm, with glabrous columnar basal part and pubescent at 2 cm above base; stigma ca. 4.5 × 3 mm, with 2 lobes initially cohering together, fluted, wholly exserted. Floral disk annular. Berry to 2 × 1.5 cm, tomentose, crowned by remnants of calyx and a large yellow disk, lacking ribs; petiole to 2.5 cm; seeds to 6.
● Rocky crevices in moist forests of limestone areas; 200-400 m. SW Guangxi [?Vietnam].