Calotropis gigantea (PROSEA)

Plant Resources of South-East Asia Introduction

List of species

Calotropis gigantea (L.) Aiton f.

Protologue: Hort. kew. 2, 2: 78 (1810).

Synonyms

• Asclepias gigantea L. (1753).

Vernacular names

• Crown flower, giant Indian milkweed (En).
• Faux arbre de soie, mercure végétal (Fr)
• Indonesia: bidhuri (Sundanese, Madurese), sidaguri (Javanese), rubik (Aceh)
• Malaysia: remiga, rembega, kemengu
• Philippines: kapal-kapal (Tagalog)
• Laos: kok may, dok kap, dok hak
• Thailand: po thuean, paan thuean (northern), rak (central)
• Vietnam: bồng bồng, lá hen, nam tì bà.

Distribution

From India and Sri Lanka to Thailand and southern China, naturalized in Malesia and Hawaii in coastal areas, and planted in villages.

Uses

The French name "mercure végétal" refers to its use as an alternative to mercury in the treatment of syphilis. Immigrants from India in South-East Asia use it widely, and the uses have thus spread. The leaves are applied as a poultice for sores, and the juice is dropped into deaf ears and sore eyes. The smoke of the burnt leaves is inhaled to treat ulcerations of the nose. The latex is dropped into teeth with caries, and is applied to boils.

Observations

• A large shrub or small tree, 3-4(-10) m tall, stems erect, up to 20 cm in diameter.
• Leaves broadly elliptical to oblong-obovate, 9-20 cm × 6-12.5 cm, subsessile; cymes 5-12.5 cm in diameter, peduncle 5-12 cm long, pedicel 2.5-4 cm long.
• Calyx lobes broadly ovate, 4-6 mm × 2-3 mm, corolla 2.5-4 cm in diameter, lobes broadly triangular, 10-15 mm × 5-8 mm, pale lilac, cream coloured towards the tips, corona with 5 narrow scales, fleshy, laterally compressed, 5-8 mm long, adnate to and shorter than the staminal column, forming an upturned horn with 2 obtuse auricles on either side, cream coloured or lilac to purple, with a dense longitudinal dorsal row of short white hairs.
• Follicles mostly in pairs, ovoid, boat-shaped, inflated, 6.5-10 cm × 3-5 cm.

C. gigantea is a common weed in open waste ground, roadsides and railway lines, as well as village surroundings. It is found in semi-cultivated state throughout Indo-China.

Selected sources

44,

• Burkill, I.H., 1966. A dictionary of the economic products of the Malay Peninsula. Revised reprint. 2 volumes. Ministry of Agriculture and Co-operatives, Kuala Lumpur, Malaysia. Vol. 1 (A-H) pp. 1-1240, Vol. 2 (I-Z) pp. 1241-2444.

263, 407, 739, 788, 810, 826, 990.

Authors

R. Kiew