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Oroxylum indicum

Family Name: Bignoniaceae
Common Name: Midnight Horror, Broken Bones Plant, Tree of Damocles, Indian Trumpet Flower, Beka, Blonglai, 木蝴蝶
Full Sun: 6-8h Moderate Water Tree


Family Name
Genus Epithet
Species Epithet
Name Status (botanical)
Common Names

Classifications and Characteristics

Plant Division Angiosperms (Flowering Seed Plants) (Dicotyledon)
Plant Growth Form Tree
Lifespan (in Singapore) Perennial
Mode of Nutrition Autotrophic


Native Distribution From India, Tropical China to Southeast Asia.
Native Habitat Terrestrial
Preferred Climate Zone Tropical, Sub-Tropical / Monsoonal
Local Conservation Status Exotic

Description and Ethnobotany

Growth Form It is a semi-deciduous tree, up to 27 m tall. The trunk has grey-brown bark and large leaf scars.
Foliage Leaves are compound, 2 – 4-pinnate, imparipinnate, about 50 – 130 (200) cm long. Leaflets are ovate to oblong (4 – 11 cm long and 3 – 9 cm wide) with entire leaf margin, acute to acuminate leaf tip, unequal to cuneate leaf base and 4 – 5 pairs of lateral veins. Glands are present and scattered on the underside of young and some mature leaves, near the veins axils. The leaflets wilt starting from the tip to the base of the leaf. The leafless stalks break apart at the joints and resemble limb bones as they falls.
Flowers Inflorescence occurs at the terminal in raceme, about 25 – 150 cm long. Flowers are large (7 – 10 cm long), brownish yellow to dirty violet colour, funnel-shaped. Each flower has 5 reflexed lobes, 5 stamens which is hairy at the base, 1 style which is 4 – 6 cm long, and superior ovary. The flower is bad-smelling, opens at night and wilts before sunrise. Each raceme has 1 – 2 flowers opening at any one time. The calyx persist and turn woody after the flowers have faded.
Fruits The fruit is a woody capsule that is sword-shaped (45 – 120 cm long and 6 – 10 cm wide) and pendulous. The pod turns black when ripe. Seeds are round and large (5 – 9 cm long and 2.5 – 4 cm wide), with thin transparent wings. Flowers and fruits may be found on the same tree as each branch can blooms independently of the others.
Habitat It grows in secondary forest, mostly below 1000 m altitude.
Associated Fauna The flowers are pollinated by bats such as Cave Nectar Bat (Eonycteris spelaea).
Cultivation It may shed its leaves during dry season and remain leafless for many months.
Etymology Oros, in greek, means mountain, and xylon means wood or tree. indicum refers to the country India, where the tree is naturally found there.
Ethnobotanical Uses Medicinal ( In Myanmar, a decoction of <i>Oroxylum indicum</i> bark, along with other herbs, to treat various ailments such as arthiritis, jaundice, dysentery, diarrhea, indigestion and rheumatism. In Malaysia, a decoction of the leaves is drunk to relieve stomachache, rheumatism, and wounds.)

Fauna, Pollination and Dispersal

Pollination Method(s) Biotic (Fauna) (Vertebrates (Bat))
Seed or Spore Dispersal Abiotic

Plant Care and Propagation

Light Preference Full Sun
Water Preference Moderate Water


Foliage Retention Drought / Semi-Deciduous
Mature Foliage Colour(s) Green
Foliar Type Compound
Foliar Margin Entire
Foliar Apex - Tip Acuminate

Non - Foliar and Storage

Bark Colour(s) brownish-grey.

Floral (Angiosperm)

Flower Location Terminal
Inflorescence Type Raceme
Flowering Opening Time Night (dusk to dawn)

Fruit, Seed and Spore

Fruit Type 1 Dehiscent Dry Fruit
Fruit Type 2 Capsule


References Van Steenis, C.G.G.J. (1977). Bignoniaceae. In:Van Steenis, C.G.G.J. (ed) Flora Malesiana, ser. 1, vol. 8, pp. 114–186., Alphen aan den Rijn: Sijthoff & Noordhoff International Publishers

Image Repository



Master ID 29403
Species ID 3712
Flora Disclaimer The information in this website has been compiled from reliable sources, such as reference works on medicinal plants. It is not a substitute for medical advice or treatment and NParks does not purport to provide any medical advice. Readers should always consult his/her physician before using or consuming a plant for medicinal purposes.
Species record last updated on: 22 October 2020.