Pleurospermum hookeri C. B. Cl.

This highly variable and complex taxon is wide-ranging in distribution and leaf form across the Himalayan region and SW China. Two varieties are currently recorded from China, but further revision of the taxon, together with P. giraldii and P. tsekuense, is needed.

Plants 10–40 cm, glabrous. Root dark brown, 4–6 mm across. Stem ribbed. Basal and lower petioles 3–8 cm, sheaths narrowly oblong, membranous margined; blades triangular-ovate, 5–13 cm, 3–4-ternate-pinnate; pinnae-7–9 pairs, ovate-lanceolate, 3–5 × 1.5–2.5 cm; ultimate segments linear, ca. 2 mm. Leaves gradually reduced upwards, petioles becoming wholly sheathing. Umbels 5–7 cm across; peduncles 6–12 cm; bracts 5–7, obovate-lanceolate or linear-lanceolate, 1.5–2.5 cm, margin membranous, white or tinged brown, apex long-caudate or occasionally pinnatifid; rays 6–12, 2–4 cm, subequal, ribbed; bracteoles 6–10, ca. 5 mm, similar to bracts, pedicels numerous, ca. 5 mm, flattened. Calyx teeth narrowly triangular, ca. 1 mm. Petals rounded, 1–1.2 mm, white. Anthers dark purple. Fruit ovoid, 3–4 mm; ribs narrowly winged; vittae 3 in each furrow, 6 on commissure. Fl. and fr. Aug–Oct.

Himalaya (Kashmir to Bhutan), Tibet, W. China (Szechuan).

Gansu, Qinghai, Sichuan, SE Xizang, NW Yunnan [Bhutan, Nepal, Sikkim].

3900-5200 m

Open pastures by streams, grassy slopes; 2700–5400 m.