西南乌头 xi nan wu tou

Caudex obconical, ca. 5 cm, ca. 18 cm in diam. Stem twining, branched, apically sparsely spreading or retrorse pubescent. Leaves long petiolate; petiole ca. 7 cm, retrorse pubescent or nearly glabrous; leaf blade orbicular-pentagonal, ca. 7.5 × 10 cm, both surfaces sparsely pubescent or nearly glabrous, base cordate, 3-sect or -parted to base; central segment rhombic or ovate-rhombic, apex acuminate; lateral segments obliquely flabellate, unequally 2-parted. Inflorescence 4--8-flowered; rachis densely spreading yellowish pubescent; bracts linear. Pedicels appressed white pubescent or subglabrous, or spreading yellowish glandular pubescent, 1.3--3 cm, with 2 bracteoles at middle or below; bracteoles linear, 3--8 × 0.3--0.5 mm, densely spreading pubescent. Sepals blue-purple, abaxially sparsely pubescent; lower sepals ca. 1.3 cm; lateral sepals 1.2--1.4 cm; upper sepal high galeate or cylindric-galeate, 2--2.4 cm high, shortly beaked, 1.4--1.6 cm from base to beak, lower margin slightly concave. Petals glabrous; lip ca. 4.5 mm; spur incurved, ca. 3 mm. Stamens glabrous; filaments entire or 2-denticulate. Carpels (3--)5, yellowish pubescent or glabrous. Follicles 1.1--1.4 cm. Seeds ca. 2.5 mm. Fl. Jul--Nov. 2n = 16*.

* Mountains, forests; 2200--3200 m. W Guizhou, SW Sichuan, Yunnan.