10. Arabis axilliflora (Jafri) H. Hara, J. Jap. Bot. 47: 107. 1972.
腋花南芥 ye hua nan jie
Parryodes axilliflora Jafri, Notes Roy. Bot. Gard. Edinburgh 22: 207. 1957; Arabis axilliflora var. brevistyla H. Hara.
Herbs perennial, 3-20 cm tall, with a branched caudex covered with leaf remains of previous years, sparsely to moderately pilose, with simple and stalked forked trichomes. Stems erect, 1 or few from caudex. Basal leaves rosulate; petiole (0.5-)1.5-5 cm; leaf blade spatulate or oblanceolate, (0.5-)1.5-5 × (0.3-)0.7-1.5 cm, pilose throughout or only along margins and midvein, base attenuate, margin entire or denticulate, apex rounded. Cauline leaves 1-3, sessile, sometimes absent; leaf blade oblong, oblanceolate, spatulate, or obovate, 1-4 × 0.5-1.5 cm, base cuneate, margins entire or few toothed. Racemes bracteate throughout; bracts similar to cauline leaves but progressively smaller upward. Fruiting pedicels (0.3-)0.7-2(-2.5) cm, divaricate to divaricate-ascending, straight or slightly recurved. Sepals spreading, light purple, oblong-ovate, 4-7 × 1.5-2.5 mm, lateral pair saccate. Petals purple, spatulate or narrowly obovate, 0.7-1.5 cm × 3-6 mm, apex rounded. Filaments 4-11 mm; anthers oblong, 1-1.3 mm. Ovules 28-40 per ovary. Fruit 2.5-5.5 cm × 1.5-2 mm; valves glabrous, with a prominent midvein extending full length; style slender, 1-3 mm. Seeds dark brown, ovate, 1.2-1.5 × 0.9-1 mm, wingless. Fl. Jun-Jul, fr. Jul-Aug.
Mountain slopes, cliffs, ledges; 3600-5000 m. S Xizang [Bhutan].
The holotype of Arabis venusta H. Hara (J. Jap. Bot. 47: 108. 1972, described from Bhutan) probably represents a small-flowered form or variety of A. axilliflora. Except for its small flowers (sepals 2.5-3.5 mm, petals 5-6 mm), it is indistinguishable from the latter species. In fact, the holotype of A. axilliflora var. brevistyla (sepals 4-5 mm, petals 7-12 mm ) falls exactly halfway between those of A. axilliflora and A. venusta. Both species were recognized in Fl. Bhutan (1(2): 435. 1984), and it appears that poor sampling resulted in the recognition of three taxa instead of perhaps only one.