岩乌头 yan wu tou

Caudex obconical, 2.3--3.6 cm, 0.9--1.1 cm in diam., or subterete, ca. 7 cm, ca. 5 mm in diam. Stem 40--65 cm tall, glabrous, with leaves equally arranged along stem. Proximal cauline leaves withered at anthesis; middle ones shortly petiolate; petiole terete, 2.2--3 cm, glabrous; leaf blade pentagonal, sometimes orbicular-rhombic, 5.5--9 × 8--10 cm, leathery, glabrous, base cordate or shallowly cordate, 3-parted; central lobe ovate-rhombic, apex long acuminate; lateral lobes obliquely flabellate; distal leaves smaller, broadly ovate or rhombic, 3-fid slightly beyond middle, sometimes narrowly ovate, almost unlobed. Inflorescence 2.2--3 cm, 1--6-flowered; rachis and pedicels glabrous; bracts ovate or narrowly ovate. Pedicels slightly decurved, ca. 1 cm, with 2 bracteoles at middle; bracteoles lanceolate-linear to broadly ovate or rhombic, 3--12 × 1.5--9.5 mm, nearly glabrous. Sepals blue, glabrous; lower sepals ca. 2.1 cm; lateral sepals ca. 2.2 cm; upper sepal cylindric-galeate, 2.4--3.2 cm high, lower margin slightly concave, 1.5--2.4 cm. Petals glabrous; claw long; lip ca. 6 mm; spur incurved, 5--7 mm. Stamens glabrous; filaments 2-denticulate or entire. Carpels 3, glabrous. Follicles 1.6--1.8 cm. Seeds ca. 2 mm. Fl. Sep--Oct. 2n = 16*.

* On rocks in valleys and forests; 1600--2800 m. Guizhou, W Hubei, Sichuan, NE Yunnan.