21. Rheum sublanceolatum C. Y. Cheng & T. C. Kao, Acta Phytotax. Sin. 13(3): 82. 1975.
窄叶大黄 zhai ye da huang
Herbs 30-55 cm tall. Stem erect, hollow, 5-8 mm in diam. at base, glabrous. Basal leaves 3-5; petioles short, 3-6 cm, glabrous; leaf blade purple-red abaxially, narrowly ovate or broadly lanceolate, 5-15 × 3-5.5 cm, leathery, glabrous, basal veins 3-5, palmate, middle one stout, base rounded, margin entire or rarely sinuolate, apex acute. Stem leaves 1 or 2 or absent, very shortly petiolate, nearly lanceolate or ovate-triangular, small; ocrea ca. 1 cm, membranous when dry, glabrous, clasping. Panicle narrow, 18-25 cm, only once branched, sparse, glabrous or sparsely papilliferous. Pedicel 2.5-3 mm, jointed below middle. Flowers 4- or 5-fascicled. Tepals 6, narrowly elliptic, outer 3 smaller, ca. 1.5 mm. Filaments subequal to perianth, slightly compressed. Ovary ellipsoid or obovoid; stigma inflated. Fruit ovoid-ellipsoid, 7.5-8.5 × 6-6.5 mm, base subcordate, apex round; wings red, narrow, ca. 1.5 mm wide, slightly membranous, with longitudinal veins at middle. Seeds brown, ovoid. Fl. Jun, fr. Aug.
* Slopes; 2400-3000 m. Gansu, Qinghai, Xinjiang.