蔓乌头 wan wu tou

Caudex unknown. Stem twining, branched, glabrous or apically sparsely retrorse pubescent. Middle cauline leaves long petiolate; petiole 3.5--6 cm; leaf blade pentagonal, 7--9 × 8--10 cm, papery, abaxially glabrous or nearly so, adaxially sparsely appressed pubescent, base cordate, 3-sect; central segment usually stipitate, rhombic-ovate; lateral segments obliquely flabellate, unequally 2-fid or nearly to base. Inflorescence terminal or axillary, 3--5-flowered; rachis and pedicels densely spreading yellowish pubescent, or retrorse and appressed pubescent; basal bracts 3-fid, others linear. Pedicels 2--3.8 cm, with 2 bracteoles above middle; bracteoles linear, 2--3 mm. Sepals blue-purple, abaxially spreading pubescent, or retrorse and appressed pubescent; lower sepals 0.8--1.3 cm; lateral sepals 1--1.5 cm; upper sepal high galeate, 1.8--2.7 cm, 1--1.5 cm from base to beak, lower margin oblique upward. Petals glabrous; limb 6--10 mm; lip 3--6 mm; spur incurved, 1.5--3 mm. Stamens glabrous; filaments entire. Carpels 5, glabrous or ovary spreading pubescent. Follicles 1.5--1.7 cm. Seeds ca. 2.5 mm. Fl. Aug--Sep. 2n = 16*.

Grassy slopes, forests, forest margins; 200--1000 m. Heilongjiang, Jilin, Liaoning [Mongolia, Russia (Siberia)].