深山唐松草 shen shan tang song cao

Plants 50--70 cm tall, glabrous. Roots tuberous. Stems branched, smooth. Basal leaf 1, 25--30 cm; petiole 11--19 cm; leaf blade 3-ternate, 13--23 cm; leaflet blade ovate or rhombic-elliptic, 4--4.5 × ca. 3.5 cm, herbaceous, base rounded or subcordate, apex 3-lobed; veins raised abaxially. Cauline leaves 2, opposite, 3.5--6 cm; leaf blade 3-ternate. Inflorescence paniculate. Bracts ternate. Sepals early deciduous, elliptic, ca. 2 mm. Filament base filiform, apex oblanceolate, ca. 3 × as broad as anther; anther ovate, ca. 0.5 mm. Carpels 3--5; style absent; stigma capitate, small. Achene stipe ca. 1.6 mm; body obliquely narrowly ellipsoid, ca. 3.5 mm. Fl. Jun--Jul.

Scrub, slopes. 800--1100 m. Heilongjiang, Jilin, Liaoning [Japan, Korea, Russia (Siberia)].

This species is similar to Thalictrum filamentosum, which differs in having cauline leaves 2, opposite, and simple; it is also similar to T. acutifolium, which differs in having rootlets without tubers and cauline leaves often alternate.