Aconitum ambiguum Rchb.

Caudex unknown. Stem (28--)50--100 cm, simple or 1- or 2-branched below inflorescence, glabrous, with leaves equally arranged along stem. Proximal cauline leaves withered at anthesis, and middle ones long petiolate; petiole 4--8 cm, glabrous; leaf blade orbicular-pentagonal, 4.6--7 × 6--12.5 cm, both surfaces glabrous, 3-sect; central segment rhombic, base narrowly cuneate, apex shortly acuminate, dissected nearly to midvein, ultimate lobes lanceolate to linear, 2--4 mm wide; lateral segments obliquely flabellate, unequally 2-parted nearly to base. Inflorescence (1--)3--5-flowered; rachis and pedicels glabrous; proximal bracts leaflike, distal ones 3-fid or linear. Pedicels 1--8.5 cm, distally with 2 bracteoles; bracteoles linear, 2.5--6.5 × 0.3--1 mm. Sepals purple-blue, abaxially glabrous; lower sepals 5--9 mm; lateral sepals 0.9--1.1 cm; upper sepal galeate, 1.3--1.5 cm high, shortly beaked, lower margin ca. 1.5 cm. Petals glabrous; limb ca. 7 mm; lip ca. 5 × 1 mm; spur short, ca. 1 mm. Stamens glabrous; filaments 2-denticulate. Carpels 3--5, glabrous. Fl. Aug. 2n = 32*.

Heilongjiang [Mongolia, Russia (Far East, Siberia)].

Forests, forest margins; 400--500 m.

Aconitum ambiguum f. multisectum S. H. Li & Y. H. Huang.