40. Cardamine paucifolia Handel-Mazzetti, Symb. Sin. 7: 359. 1931.
少叶碎米荠 shao ye sui mi ji
Cardamine yunnanensis Franchet var. obtusata C. Y. Wu ex T. Y. Cheo & R. C. Fang.
Herbs perennial, 15-40 cm tall, sparsely pilose or glabrescent. Rhizomes slender. Stems simple, slightly angled. Basal leaves often withered by flowering, trifoliolate; petiole 1.5-4.5 cm; leaflets similar to those of cauline leaves, smaller. Cauline leaves 1-4, trifoliolate; petiole 1.5-6 cm, not auriculate at base; terminal leaflet lanceolate, ovate, or broadly elliptic, 3-6.5 × 1-3.5 cm, sparsely pilose or glabrous, with a petiolule 5-12 mm, base obtuse or cuneate, margin ciliate and dentate or crenate, apex acute or acuminate; lateral leaflets 2, shortly petiolulate or sessile and base decurrent to rachis, nearly as large as terminal one, base oblique. Uppermost leaf often with a sessile terminal leaflet decurrent basally with lateral leaflets. Fruiting pedicels ascending or divaricate, 7-11 mm, straight, slender. Sepals oblong, 3.5-4.5 × 1.2-1.5 mm, base not saccate. Petals white, narrowly obovate, 6-8.5 × 1.5-3.5 mm, not clawed. Median filament pairs 3.5-4 mm, lateral pair ca. 3 mm; anthers oblong, 1.1-1.6 mm. Ovules 10-16 per ovary. Fruit linear, 3-5 cm × 1-1.5 mm; valves smooth, glabrous; style 1.5-2.5 mm. Seeds brown, narrowly oblong, 1.5-2 × 0.6-0.8 mm, apically winged. Fl. and fr. Mar-Jul.
* Ravines, streamsides; 1500-2600 m. Yunnan.
Cardamine paucifolia was not mentioned in FRPS, whereas in Fl. Yunnan. (6: 59. 1995) it was reduced to the synonymy of C. trifoliolata. However, C. paucifolia is most closely related to C. yunnanensis, from which it is readily distinguished by having trifoliolate leaves, no petiolar auricles, larger flowers, glabrous fruit, and apically winged seeds.
The type collection of Cardamine yunnanensis var. obtusata, C. W. Wang 64172 (holotype, KUN; isotypes A, NAS), has no petiolar auricles and glabrous fruit, and therefore clearly belongs to C. paucifolia. By contrast, the three paratypes of this variety, T. T. Yü 16025 (A, KUN), T. T. Yü 11281 (KUN, NAS), and Handel-Mazzetti 8876 (E, WU), have distinctly auriculate petioles and pilose fruit, and they are assigned to C. yunnanensis. Also belonging to C. paucifolia is the invalidly named C. dulongensis H. Li (Fl. Dulongjiang Region, 75. 1993, nomen nudum).