四川丝瓣芹 si chuan si ban qin

Plants 15–30 cm, slender. Rhizome tuberous, ovoid, 3–25 × 4–7 mm. Stem thinly ribbed. Lower stem leaves petiolate, petioles 2–5.5 cm, sheaths short, small; blade broad-triangular, 3.5–10 × 6–12 cm, 2-ternate-pinnate; pinnae remote, petiolules 2–5 cm, pinnule petiolules 0.2–2.5 cm, semi-orbicular, 0.5–1.5 × 0.6–1.7 cm, apex 3-lobed, lobes obovate, 2–3-toothed. Uppermost leaves reduced, segments linear, entire or sparsely incised-serrate. Umbels 2–5 cm across; peduncle 3–6 cm, slender; bracts absent or 1; rays 3–6, 1.5–4.5 cm, very unequal; bracteoles absent; umbellules 5–10 mm across, 3–10-flowered; pedicels 2–9 mm, unequal, spreading in fruit. Calyx teeth triangular, minute, ca. 0.2 mm. Petals white or pink, ovate-lanceolate, ca. 3 × 0.6 mm; apex linear, ca. 2 mm. Fruit broad-ovoid, ca. 2 × 3 mm, base cordate; vittae 2–3 in each furrow, 2–4 on commissure. Fl. Jun–Jul, fr. Aug–Sep.

Forests, damp shady crevices; 3200–4000 m. S Qinghai, SW Sichuan, S Xizang, NW Yunnan [?Bhutan, ?Sikkim].

Plants from the E Himalayas are smaller (2.5–6.5 cm), with almost sessile, lax umbels. They may represent a different, as yet undescribed species, but further work and new collections are needed to confirm this.