Strobilanthes cusia Kuntze-Assam indigo, Chinese rain bell

 Strobilanthes cusia Kuntze, Revis. Gen. Pl. 2: 499 (1891).

Strobilanthes cusia (Nees) Kuntze; Photos Hoang Thanh Son

Vietnamese name: 

Chàm mèo; Phẩm rô; chàm nhuộm; chàm lá to; mã lam; thanh đại.

Chinese name: 

板蓝 ban lan

English name: 

Assam indigo, Chinese rain bell, room

Latin name: 

Strobilanthes cusia (Nees) Kuntze 

Family: 

Acanthaceae 

Synonym name:

Baphicacanthus cusia (Nees) Bremek.

Dipteracanthus calycinus Champ.

Goldfussia cusia Nees

Ruellia indigofera Griff.

Ruellia indigotica Fortune

Strobilanthes balansae Lindau

Strobilanthes championii T.Anderson ex Benth.

Strobilanthes flaccidifolia Nees

Description: 

Herbs 0.5-1.5 m tall, erect, branched, drying blackish, isophyllous to weakly anisophyllous. Stems glabrous or minutely brown puberulent. Petiole 0.5-7 cm; leaf blade elliptic to ovate, 4-20 × 2-9 cm, both surfaces glabrous or abaxially minutely puberulent along veins, abaxially paler green, adaxially dark green, secondary veins 7-9 on each side of midvein, base attenuate, margin serrate, apex acute. Inflorescences terminal or axillary, bracteate spikes, 1-6 cm, often aggregated to form a leafy branched panicle; peduncle 1-12 cm; bracts leaflike, petiolate, oblanceolate, obovate, or spatulate, 1.2-2.5 cm, basally usually sterile; bracteoles linear-oblanceolate, 2-3 mm, deciduous before bracts. Calyx 0.8-1.5 mm in flower, accrescent to ca. 2.5 cm in fruit, minutely puberulent, 5-lobed almost to base; 4 lobes linear-lanceolate, apex acute to obtuse; 1 lobe oblanceolate and much longer. Corolla blue, 3.5-5 cm, straight to slightly bent, outside glabrous; tube basally cylindric and ca. 3 mm wide for 1-1.5 cm then slightly curved and gradually widened to ca. 1.5 cm at mouth; lobes oblong, ca. 9 × 9 mm, subequal. Stamens 4, included; filaments glabrous, shorter pair ca. 3 mm, longer pair ca. 7 mm; anther thecae oblong, ca. 3 mm; pollen type 4. Ovary oblong, apex puberulent with few gland-tipped trichomes; style ca. 3.2 cm, glabrous. Capsule 1.5-2.2 cm, glabrous, 4-seeded. Seeds ovate in outline, ca. 3.5 mm, covered with appressed trichomes; areola small. 2n = 16, 32. 

Flower and fruid season: 

Fl. Jul-Feb, fr. Dec-Feb 

Distribution: 

This species is distributed in China (Fujian, Guangdong, Guangxi, Guizhou, Hainan, Hunan, Sichuan, Taiwan, SE Xizang, Yunnan, Zhejiang), Bangladesh, Bhutan, India, Laos, Myanmar, Thailand and VietNam. In VietNam, it found in Lào Cai, Lai Châu, Sơn La, Hà Giang, Cao Bằng, Lạng Sơn, Bắc Thái, Hà Bắc.

Ecological: 

The tree grows wild in wet valleys and rocky mountains; at elevations of 100-2000 m.

Parts used: 

Leaves (Folium Strobilanthis Cusiae)

Chemical composition: 

The indigo leaves contain 0.4-1% indican. When hydrolyzed, indican gives indoxyl and glucose. When oxidized, indoxyl gives indigotin. Indigotin has a dark blue color. There is also indirubin.

Uses: 

Eczema is used to treat children with fear, fever, fever, fever, fever, swelling of amydgal, vomiting, hemorrhage, menorrhagia, bleeding. On use 4-6g high leaves mix with sugar, or use 1-4g Thanh Dai powder with water. Use outside to take both highly cooked cat indigo to treat eczema, gingivitis, mouth, mouth sores, poisonous snakes and insect bites.

Reference: 

- theplantlist.org

- efloras.org

- ipni.org