13. Acronema nervosum H. Wolff, Repert. Spec. Nov Regni Veg. 27: 315. 1929.
羽轴丝瓣芹 yu zhou si ban qin
Plants 10–25(–40) cm. Root tuberous, ovoid, ca. 5 mm across. Stem solitary, slender, little-branched. Basal leaves petiolate, petioles ca. 5 cm, slender, sheaths small; blade broad-triangular, 2.2–3 × 1.5–2.5 cm, 2-ternate-pinnate; pinnae petiolulate; ultimate segments obovate to linear-lanceolate, 5–8 × 2–3 mm, entire or 3-toothed, margins and adaxial veins minutely pubescent. Umbels 1.5–3 cm across; peduncles short; bracts and bracteoles absent (bracts occasionally 1); rays 3–6, 1.5–2.7 cm, slender; umbellules 5–12 mm, 3–9-flowered; pedicels 2–9 mm, unequal, spreading and elongating in fruit. Calyx teeth obsolete. Petals white, yellowish-white, or purple, ovate-lanceolate, 2–3 × ca. 0.5 mm; apex linear, ca. 1.5 mm. Stylopodium depressed. Fruit ovoid, ca. 1.5 × 1.5 (mature fruit unknown). Fl. Aug–Sep, fr. Sep–Oct.
Alpine forests; 4100–4500 m. SW Sichuan, S Xizang [Bhutan, NE India, Nepal, Sikkim].
This species has reputed medicinal value (in Xizang).