Endospermum ovalifolium Pax & K.Hoffm.

A medium-sized to fairly large tree of up to 35(-40) m tall, bole stout, columnar, up to 150 cm in diameter, with thick buttresses, bark surface smooth, becoming rugose to scaly in patches, grey-fawn, inner bark thick, cream with orange flecks. Leaves non-peltate (sometimes peltate in saplings), obovate to broadly ovate or cordate, 7-25 cm X 4-22 cm, palmately 3-9-veined, the midrib with 3-5 pairs of lateral veins petiole with 0-2 small glands at the apex. Inflorescence long and simple or the male one with short sideaxes; male flowers with 9-11 stamens, female flowers with a 2-3-celled ovary and a 1.5 mm wide stigma. Although E. malaccensis is a full synonym of E. diadenum, it is still often used, especially within Malaysia, which causes some confusion.

Usually, trees flower every year, and in Malaysia E. diadenum often even flowers twice a year. Mature fruits are present 2-3 months after flowering. Trees 3 years old may already produce viable seeds. E. diadenum is strictly dioecious, just like most other Endospermum species; female trees were found to have on average a thicker bark than male trees.

E. diadenum occurs in primary forest and particularly in secondary forest on low, undulating country or along streams and occasionally on permanently inundated sites. Sometimes in association with Sapium baccatum Roxb. Although Endospermum is often found in assocation with other typical swamp forest species, but especially E. diadenum, are known as opportunist species characteristic of gaps in the forest and hence are common in areas with shifting cultivation.

Seed of E. diadenum are often heavily predated by insects, making it difficult to obtain viable seeds. In Malaysia it is suggested to used wildlings for planting because seed is scarce. Transplanted wildlings suffer high mortality unless care is taken to minimize root damage, but with appropriate care the survival rate may be as high as 70%. The survival rate of young trees of E. diadenum after 2 years is 70-90%.

Pests: In Peninsular Malaysia, fruits of E. diadenum are subject to a high degree of insect predation, resulting in a very small proportion of seeds reaching maturity. E. diadenum can be heavily defoliated by caterpillars of the moth Uraptevoides astheniata, with devastating effect on its growth.

Reclamation: It used for reforestation. Shade or shelter: As a shade tree.

Medicine: The bark is used to cure dropsy and the roots are applied to injuries. Timber: The timber is an important source of sesendok; it is one of the favourite timbers for clogs.