Marsdenia tinctoria R. Br.

The bark, leaves, and flowers are used in making a blue dye.

As here delimited, Marsdenia tinctoria includes a wide range of forms which need more detailed investigation, and several taxa might be involved. There is also considerable variation in the relative length of corona to anthers and in the size, shape, and indumentum of fruits. The Chinese material has distinctly narrower and often paler leaves than Indian material and also lacks the very long spiral rachis of typical M. tinctoria. Marsdenia globifera was based on material with diseased flowers.

Lianas to 5 m, densely to sparsely pubescent when young, glabrescent. Petiole 1-4 cm; leaf blade oblong to broadly ovate, 5-13 × 2-7 cm, thin papery, bluish when dry, base rounded to cordate, apex acuminate; lateral veins 5-7 (-10) pairs. Inflorescences dense, globose to long racemelike clusters of cymules, (1.5-)3-15 cm; peduncle (0.5-)2.5-5 cm. Pedicel 3-5 mm. Sepals suborbicular, ca. 2 mm. Corolla yellowish white, dark blue when dry, urceolate, 3.5-4(-6) mm long, throat with a ring of hairs, otherwise glabrous; tube ca. 2.5 mm; lobes ovate, 1-1.5 mm, apex rounded. Corona lobes 5, lanceolate, as long as anthers. Pollinia narrowly oblong. Stigma head discoid, slightly convex at apex. Follicles oblong-lanceolate, 5-10 cm × 8-10 mm, pilose to subtomentose. Seeds ovate, ca. 10 × 3 mm; coma 1-2 cm. Fl. Mar-Nov, fr. Jul-Dec.

Subtropical Himalaya (Nepal to Bhutan), Assam, east to W. & S. China, Taiwan, Malaysia.

Guangdong, Guangxi, Guizhou, Hainan, Hubei, Hunan, Sichuan, Taiwan, Xizang, Yunnan [Bhutan, India, Indonesia, Japan (Ryukyu Islands), Laos, Malaysia, Myanmar, Nepal, Philippines, Sri Lanka, Thailand, Vietnam]

500-1200 m

Humid mixed woods; 400-1000 m.

Marsdenia globifera Tsiang; M. tinctoria var. brevis Costantin; M. tinctoria var. tomentosa Masumune ex Tsiang & P. T. Li.

Marsdenia tinctoria là một loài thực vật có hoa trong họ La bố ma. Loài này được R. Br. mô tả khoa học đầu tiên năm 1810.

蓝叶藤（学名：Marsdenia tinctoria）是夹竹桃科牛奶菜属的植物。分布在斯里兰卡、印度、缅甸、印度尼西亚、越南、菲律宾、台湾岛以及中国大陆的西藏、四川、云南、贵州、湖南、广西、广东等地，生长于海拔200米至1,800米的地区，见于潮湿杂木林中。