Arabis serrata Franch. & Sav.

Arabis serrata is highly variable in basal leaf indumentum, margin, and petiole length. Of the many taxa synonymized above, none seems to merit recognition. In fact, A. formosana is indistinguishable from some of the Japanese forms of A. serrata.

Herbs perennial, (5-)12-35(-45) cm tall, densely to sparsely pilose, with minute, short-stalked or subsessile, submalpighiaceous and 3-5-rayed, stellate trichomes, rarely glabrescent or with some simple ones near stem base. Stems erect, single or few from base. Basal leaves rosulate; petiole (0.5-)1-4(-6) cm; leaf blade spatulate, oblanceolate, obovate, or narrowly oblong, (1-)2-7(-14) × (0.5-)1-2(-3) cm, base cuneate or attenuate, margin entire, dentate, or rarely lyrate-sinuate, apex obtuse or rounded. Middle cauline leaves sessile, oblong or ovate, (1-)2-4(-6) × 0.5-2.5(-3.5) cm, base cordate or amplexicaul, margin dentate or entire. Racemes ebracteate. Fruiting pedicels ascending or divaricate, (0.5-)0.8-2(-2.5) cm, slender, straight, often glabrous. Sepals oblong, 3.2-4 × 1.2-1.8 mm, glabrous, lateral pair saccate. Petals white, rarely pinkish, oblong-oblanceolate, 7-10 × (1.5-)2-3(-3.5) mm, apex truncate-emarginate. Filaments 4-5 mm; anthers oblong, 1-1.4 mm. Ovules 28-60 per ovary. Fruit (2-)3.5-7(-8) cm × 1-1.5 mm, erect, divaricate, or rarely reflexed; valves with an obscure or distinct midvein, torulose, glabrous; style 1-2.5 mm. Seeds brown, oblong or rarely suborbicular, (1-)1.5-2(-2.5) × 0.8-1 mm, uniseriate, broadly winged apically; wing 0.3-0.6 mm wide. Fl. Apr-Jun, fr. May-Aug. 2n = 32.

Anhui, Taiwan [Japan, Korea].

Rocky crevices, along streams, mountain slopes, deciduous forest; 100-3200 m.

Arabis alpina Linnaeus var. formosana Masamune ex S. F. Huang; A. amplexicaulis Edgeworth var. japonica H. Boissieu; A. amplexicaulis var. serrata (Franchet & Savatier) Makino; A. boissieuana Nakai; A. boissieuana var. glauca (H. Boissieu) Koidzumi; A. boissieuana var. sikokiana Nakai; A. fauriei H. Boissieu (1899), not H. Léveillé (1910); A. fauriei var. grandiflora Nakai; A. formosana (Masamune ex S. F. Huang) T. S. Liu & S. S. Ying; A. glauca H. Boissieu; A. glauca subsp. pseudoauriculata (H. Boissieu) Voroschilov; A. hallaisanensis Nakai; A. iwatensis Makino; A. kishidae Nakai; A. pseudoauriculata H. Boissieu; A. serrata var. glabrescens Ohwi; A. serrata var. glauca (H. Boissieu) Ohwi; A. serrata var. platycarpa Ohwi; A. serrata var. japonica (H. Boissieu) Ohwi; A. serrata var. sikokiana (Nakai) Ohwi; A. sikokiana (Nakai) Honda.