Articles

Mitragyna speciosa (Korth.) Havil.

 

Mitragyna speciosa (Korth.) Havil.

Family

Rubiaceae

Synonyms

Nauclea speciosa Miq.

Vernacular Names

Malaysia Ketum, kutum, biak-biak.
Indonesia Kadamba (Kalimantan), purl (Batak Toba).
Thailand Bai krathom, ee-thaang (Central), thorn (Peninsular).
Vietnam Giam d[ef]p, giam l[as] nh[or].
Philippines Mambog (Tagalog), lugub (Mandaya), polapupot (Ibanag).

Geographical Distributions

Mitragyna speciosa is found from Peninsular Malaysia, Sumatra and Borneo to the Philippines and New Guinea. It is cultivated in southern Vietnam, peninsular Thailand and Burma (Myanmar).

Description

M. speciosa is a large tree, which can reach 10-30 m tall. The big bole measures 60-100 cm in diametre. The bark is grey, shallowly sculptured and with blister-like prominent lenticels.

The leaves are opposite, simple, entire, oblong-ovate and measure 8-15cm x 4-10 cm. The leaf base is broadly rounded, apex abruptly acuminate, smooth or veins beneath covered with soft short hairs, veins 12-15 pairs and stalk is measures (1-)2-5 cm long. The stipules are lance-shaped, measure 2 cm long, with soft hair, 9 veins and with colleters inside at the base.

The inflorescence is terminally on lateral branches, composed of 3(-7) spherical heads, where 1 head is nearly subsessile between the 2 others on long peduncles which are 5 cm long and head 2.5 cm in diametre when flowering, shortened to 1.5 cm when fruiting with receptacle hairy and leafy bracts measuring up to 4 cm long. The petiolate is between flower bracteoles measuring up to 3.5 mm long. The flowers are bisexual, 5-merous, sessile with cup-shaped sepal, measuring up to 2 mm long and 5-lobed. The funnel shaped petals are yellowish-white turning deep yellow which are 5-8 mm long with 5 lobes that are 3 mm long and thickened at apex while margin is revolute. There is a conspicuous ring of hairs inside at the base of its lobes. The stamens are 5 which intersection with lobes while anthers are lance-shaped, heart-shaped and conspicuously protruding from the petal with ovary inferior consists of 2-celled. The style is exserted with 13 mm long while the stigma is rounded and 2 mm long.

The fruit composed of 2 cocci, exocarp thin, splitting from the dorsal suture along its length and 10-ridged. The seeds are numerous and shortly winged on 2 sides while the lower wing shortly bifid or notched.

Ecology / Cultivation

M. speciosa generally occurs rather sparsely in open savanna, secondary forest and at low altitudes. In Borneo, it is usually encountered in swamp and riverine forests which are periodically flooded, where it is one of the dominant species observed as colonising vegetation on old ox-bow riverbeds.

Line Drawing / Photograph

Mitragyna_speciosa

Read More

  1) Safety

  2) Malaysian Herbal Plants

References

  1. Plant Resources of South-East Asia No 12(2): Medicinal and poisonous plants 2.