Flowering from June to July; fruiting from July to August.
Viola biflora var. rockiana is close relative of Viola biflora var. biflora, but differs from the latter in its leaf blade orbicular or nearly reniform (vs. reniform or broadly ovate).
Viola biflora var. rockiana is occurring in Gansu, Qinghai, Sichuan, E Xizang, Yunnan of China.
Herbs perennial. Rhizome erect or obliquely ascending, slender or slightly robust, noded, with numerous rootlets. Stems 2-3 fasciculate, erect or obliquely ascending, slender, up to 10 cm tall, 2-noded, glabrous. Leaves only in lower part, leaf blade orbicular or ovate-orbicular, ca. 1 cm long, 1 cm wide, abaxially glabrous, adaxially sparsely puberulous, sometimes puberulous on both surfaces, base shallowly cordate or subtruncate, margin shallowly repand-crenate, apex obtuse. Stipules free, ovate or ovate-lanceolate, margin entire or remotely denticulate, apex acute. Flowers yellow, sometimes whitish at late anthesis; pedicels 1-6 cm long, slender, 2-bracteolate at upper part; bracteoles lanceolate. Sepals linear-lanceolate or lanceolate, apex acute, basal auricles very short, margin membranous, glabrous or shortly ciliate in middle and lower parts. Petals oblong-obovate, purple veined, lateral ones inside not barbate; spur shallowly saccate; spur of anterior stamens shortly triangular. Ovary glabrous; styles clavate, base slightly geniculate, deeply 2-lobed in upper half, lobes obliquely spreading, with a conspicuous stigma hole in between lobes. Capsule oblong-ovoid, glabrous.
The chromosomal number of Viola biflora var. rockiana is 2n = 12 (Funamoto et al., 1995).
Growing in thickets, alpine grassy slopes; 2800-4000 m.
