Cardamine nudicaulis Linnaeus, Sp. Pl. 2: 654. 1753; Achoriphragma ajanense (N. Busch) Soják; A. nudicaule (Linnaeus) Soják; Arabis nudicaulis (Linnaeus) de Candolle; Cheiranthus scapiger Adams; Hesperis arabidiflora de Candolle; H. scapigera (Adams) de Candolle; Matthiola nudicaulis (Linnaeus) Trautvetter; Neuroloma ajanense (N. Busch) Botschantzev; N. arabidiflorum (de Candolle) de Candolle; N. griffithii Botschantzev; N. nudicaule (Linnaeus) Andrzejowski ex de Candolle; N. scapigerum (Adams) de Candolle; N. speciosum Steudel; Parrya ajanensis N. Busch; P. arabidiflora (de Candolle) Nicholson; P. integerrima G. Don; P. linnaeana Ledebour; P. macrocarpa R. Brown; P. scapigera (Adams) G. Don.
Plants (4-)10-35(-45) cm tall, cespitose, glandular throughout or eglandular, glabrous; caudex branched, covered with petiolar remains of previous years. Basal leaves rosulate; petiole often becoming thickened, (0.5-)2-10(-15) cm, glabrous or rarely sparsely ciliate; leaf blade lanceolate, linear, spatulate, or oblong, (1.2-)3-11(-14) cm × 4-10(-15) mm, base cuneate or attenuate, margin dentate to dentate-sinuate, rarely subpinnatifid or repand, apex acute. Cauline leaves absent. Racemes 2-20-flowered. Fruiting pedicels erect-ascending or divaricate, lowermost (1.5-)2.2-7(-11) cm. Sepals linear to linear-oblong, 6-11 × 1.5-3 mm, glabrous or glandular, white margined. Petals pink with a yellowish center, rarely white or purple, broadly obovate, (1.4-)1.6-2(-2.2) cm × 6-10 mm, apex rounded to shallowly emarginate; claw 0.8-1.2 cm. Filaments white, median pairs 6-8 mm, lateral pair 3-5 mm; anthers linear, 2.5-3 mm. Ovules 16-40 per ovary. Fruit linear to linear-lanceolate, (3-)4-7(-9) cm × (3.5-)4-7 mm; valve margin flat; replum flattened; style 0.5-1.5(-3) mm; stigma 0.5-1.5 mm. Seeds suborbicular, 3-8 mm in diam., flattened, broadly winged; wing (0.5-)1-3 mm wide. Fl. May-Aug, fr. Jul-Sep.
Dry stony hillsides, rocky crevices, among boulders, scree; 2200-5500 m. Qinghai, Xizang [Afghanistan, Bhutan, India, Kashmir, Russia, Sikkim; North America].
The records of Parrya fruticulosa Regel & Schmalhausen in FRPS and Fl. Xinjiang. (2(2): 175. 1995) were based on misidentified plants of the highly variable P. nudicaulis. The present authors have seen no Chinese material of P. fruticulosa, which is endemic to Tajikistan (Pamir Alai) and adjacent Uzbekistan. It is a shrub or subshrub with leafy, strongly woody stems and narrowly linear, entire leaves.
