窄翅南芥 zhai chi nan jie

Arabidopsis yadungensis K. C. Kuan & Z. X. An; Arabis alpina Linnaeus var. purpurea W. W. Smith; A. latialata Y. C. Lan & T. Y. Cheo.

Herbs biennial or short-lived perennial, (10-)20-60(-80) cm tall, densely or rarely sparsely hirsute, primarily with simple trichomes, these often mixed at least distally with long-stalked, forked or rarely stellate ones. Stems erect, simple from base, simple or branched above. Basal leaves rosulate; petiole often absent, rarely distinct and to 4 cm; leaf blade spatulate, oblanceolate, narrowly obovate, or oblong, (1-)2-7(-9) × (0.5-)1-2(-3) cm, base attenuate, margin dentate, serrate, or rarely entire, often ciliate, apex obtuse or acute. Middle cauline leaves sessile, oblong, elliptic, or ovate-lanceolate, (1-)2-4(-5) cm × (2-)4-10(-15) mm, hirsute, with predominantly simple trichomes, base auriculate, cordate, or rarely amplexicaul, margin dentate or entire, apex obtuse or acute. Racemes ebracteate. Fruiting pedicels erect or rarely ascending, often subappressed to rachis, 4-10(-16) mm, slender, straight. Sepals oblong or sublanceolate, 2.5-3.5 × 1-1.5 mm, often glabrous, not saccate. Petals purple, pink, or rarely white, oblong or narrowly oblanceolate, 6-9 × 2-3 mm, apex obtuse. Filaments 3.5-5 mm; anthers oblong, 0.6-1 mm. Ovules 40-80 per ovary. Fruit (2.5-)3-5(-6) cm × 1.5-2 mm, erect, appressed to rachis; valves with a prominent midvein extending full length, torulose, glabrous; style 0.5-1 mm. Seeds brown, orbicular to ovate-orbicular, 1-1.6 mm in diam., uniseriate, broadly winged all around; wing (0.1-)0.2-0.4 mm wide. Fl. (Mar-) May-Jul, fr. Jun-Oct.

Roadsides, woodlands, grassy slopes, alpine meadows; 2900-4300 m. Qinghai, Sichuan, Xizang, Yunnan [Bhutan, India, Kashmir, Pakistan, Nepal, Sikkim].

The above first record from Sichuan is based on Wilson 3215 (A) and Guan Kejian & Wang Wencai 239 (MO, PE); the above first record from Yunnan is based on K. M. Feng 1239 & 2473 (A).

Arabis alpina var. purpurea was listed in FRPS as a synonym of A. paniculata. However, an examination of the type collection of the former (Forrest 13977; holotype, E; isotypes, K, P) clearly shows that it is indistinguishable from plants of A. pterosperma. The type collections of A. latialata and Arabidopsis yadungensis represent fruiting and flowering material, respectively, of A. pterosperma.