澜沧唐松草 lan cang tang song cao

Plants 17--70 cm tall, glabrous. Stems branched, erect. Leaves both basal and cauline; stipules leaflike, 1--6 mm, membranous; petiole 0.8--15 cm; leaf blade 1- or 2-ternate, 5--10 cm; petiolule 0.5--1.2 mm; leaflet blade orbicular or cuneate-obovate, 0.7--2.2 × 0.7--2.9 cm, papery, base cordate, margin 3(--9)-lobed; lobes crenate, apex obtuse or sometimes very shortly mucronate; veins abaxially prominent, adaxially inconspicuous. Inflorescence terminal or axillary, paniculate, several flowered. Sepals 4, early deciduous, white, obovate, 3.7--4.2 mm. Stamens ca. 30; filament whitish, 2.4--2.7 mm, apex strongly dilated, narrower than anther; anther ca. 1--1.2 mm, apex obtuse. Carpels (5--)9--15; style 1.5--2.2 mm; stigma conspicuous. Achenes shortly stipitate; body narrowly cylindric-ovoid, 2.5--3 mm; persistent style straight to circinate, 0.2--0.3 mm; veins 6--8, stout. Fl. Jun--Aug, fr. Sep--Oct.

* Sparse forests; ca. 2000 m. SW Yunnan (Lancang Lahu Zu Zizhixian).

This species is similar to Thalictrum leve, but differs in having much smaller leaflets and much longer styles.