Cratoxylum formosum (Jack) Dyer

Cratoxylum formosum (Jack) Dyer




Tridesmis ochnoides Spach, Tridesmis formosa (Jack) Korth., C. pentadelphum Turcz.

Vernacular Names

Malaysia Derum (Peninsular), geronggang biabas (Sabah), entemu(Sarawak).
Indonesia Kemutul (Sumatra), mulun, kasat bakun (Kalimantan).
Philippines Salinggogon (General, Pilipino), mango-gong, marangguub (Palawan).
Laos Tiou-tiou 'som-som.
Thailand Tiu khao (Bangkok), tiu som (Nakhon Ratchasima), muu-to (Peninsular).
Vietnam Th[af]nh ng[aj]nh d[ej]p.
Brunei Pelawan.

Geographical Distributions

Cratoxylum formosum is found in Burma, southern China, southern Vietnam, Cambodia, southern Thailand, Peninsular Malaysia, Sumatra, Java, Borneo, Sulawesi and the Philippines.


C. formosum is a medium-sized to large tree that can reach up to 45 m tall, with slightly fluted bole and spiny at the base and measuring up to 65 cm in diametre. The bark surface is papery scaly and grey-brown to red-brown or purplish. The inner bark is yellow to yellow-brown.

The leaves are elliptical or lance-shaped to ovate or obovate, measuring 3-17 cm x 1-8 cm, with acute or short acuminate to rounded at the apex and sometimes glaucous beneath.

The inflorescence consists of small 1-6-flowered cymes in the lower axils of shoots or apparently axillary on the older branches. The flowers are heterodistylous, white or pink to red or rarely purplish petals and with an entire nectary scale at the base.

The seeds are (7-)12-17 per locule and unilaterally winged.

Ecology / Cultivation

C. formosum characteristically occurs in freshwater or peat-swamp forests on sandy or sandy-loamy soils, and sometimes in coastal dipterocarp swamp forests. It generally appears scattered but sometimes locally abundant and can even become dominant. It is found in areas without a pronounced dry season (A and B rainfall types) from sea level up to 900 m altitude and in Sabah up to 1800 m altitude. It is often found in areas with shifting cultivation or other more secondary habitats. In Sabah, it is found associated with palawan (Tristania spp.) and Weinmannia blumei Planchon. In Sumatra, the main associated species are pulai (Alstonia scholaris (L.) R.Br.), terentang (Campnosperma spp.) and perupok (Lophopetalum spp.).

Line Drawing / Photograph



  1. Plant Resources of South-East Asia No. 5(1): Timber trees: Major commercial timbers.