41. Draba gracillima J. D. Hooker & Thomson, J. Proc. Linn. Soc., Bot. 5: 153. 1861.
纤细葶苈 xian xi ting li
Draba granitica Handel-Mazzetti; D. wardii W. W. Smith.
Herbs perennial, 5-55 cm tall, slender. Caudex with several slender branches terminated in rosettes. Stems decumbent, simple, very slender, somewhat flexuous, basally sparsely pubescent with short-stalked, 3- or 4-rayed, stellate trichomes, rarely densely pilose with primarily simple trichomes, apically glabrous. Basal leaves rosulate, persistent; petiolelike base to 7 mm; leaf blade broadly obovate, spatulate, to oblanceolate, 0.5-2 cm × 1.5-7(-10) mm, abaxially sparsely pubescent with short-stalked, 4-rayed stellate trichomes rarely mixed with more, simple and forked ones, abaxially pilose with simple trichomes replaced with forked or stellate ones at leaf apex, rarely blade glabrous except for margin, base cuneate to attenuate, margin denticulate or subentire, often ciliate, apex subacute or obtuse. Cauline leaves 2-6, sessile, ovate, 2-7 × 1-3 mm, pubescent as basal leaves, base obtuse, not auriculate, margin entire or denticulate, apex acute. Racemes 3-10(-12)-flowered, ebracteate or lowermost flowers bracteate, lax, elongated considerably in fruit. Fruiting pedicels 0.4-4 cm, filiform, glabrous, lowermost longest and strongly recurved, uppermost straight and ascending. Sepals oblong, 1.5-2 × 0.6-1.5 mm, erect, glabrous or rarely with a few trichomes, not saccate, margin narrowly membranous. Petals pale yellow or yellowish white, narrowly obovate to oblanceolate, 2.5-3.5 × 0.8-1.5 mm, apex obtuse or subemarginate; claw absent. Filaments 1.2-2 mm; anthers ovate, 0.2-0.4 mm. Ovules 10-20 per ovary. Fruit narrowly oblong, linear, or linear-lanceolate, (0.5-)0.7-1.3(-1.8) cm × 1-2 mm, pendulous, latiseptate, not twisted; valves glabrous, not veined; style 0.2-0.5 mm. Seeds brown, ovate, 0.9-1.1 × 0.5-0.7 mm, subcompressed, wingless. Fl. and fr. May-Aug.
Mountain slopes, grassy areas, ravines, stony slopes, scree, alpine grasslands; 3200-5000 m. Xizang, Yunnan [Bhutan, NW India, Nepal, Sikkim].
The type collection of Draba granitica, Handel-Mazzetti 9497 (holotype, WU; isotype, W), is indistinguishable from that of D. gracillima, J. D. Hooker s.n. (holotype, K; isotypes, E, K, NY, P, W), in every aspect except flower color. The former species was said to have white instead of yellowish white or pale yellow flowers, but the present authors believe that this distinction is artificial, and the two taxa are united here.
Draba wardii, which is known only from the type gathering, Kingdon Ward 849 (holotype, E), collected from Xizang, was not listed in FRPS or Fl. Xizang. (vol. 2. 1985). It is no more than a young plant of D. gracillima with simple trichomes more abundant that stellate ones.