Sonneratia ovata Backer

Columnar tree, up to 2-5(-20) m tall, with stem up to 20 cm in diameter. Stem short and usually twisted, base not buttressed, surounded by thin, pointed, pneumatophores about 20 cm long. Bark grey, smooth to slightly fissured, lenticellate, inner bark pale brown to reddish, faintly laminated, rather watery. Sapwood pale yellow, soft. Twigs distincly jointed above the nodes, quadrangular when young, terete with age, greyish brown. Leaves simple, opposite, exstipulate; petiole 2-15 mm long; blade usually ovate to orbicular or broadly ovate, 4-10 cm x 3-9 cm, base rouded or subcordate, apex broadly rounded, upper surface glossy, slightly corrugated with 9-16, fine but conspicuous lateral veins. Flowers bisexual, usually in terminal groups of 2-3(-4), occasionally solitary; pedicel 1-2 cm long, sometimes absent; buds broadly avoid, apex rounded or obtuse, finely verruculose, 1.5-3 cm x 1-1.5 cm; calyx persistent, calyx tube cup-shaped, tapering abruptly into a stalk-like base, ribbed segments usually 6, ovate-triangular, 13-15 mm long, inner surface markedly reddish cream at base; petals absent or vestigial; stamens many, filaments about 2 cm long, white, anthers yellow; ovary 10-15 celled, style about 2.5 cm long. Fruit an indehiscent, flattened globose berry, resting on the calyx-tube, 3-5 cm in diameter, 2-3 cm thick, dark green when young turning yellowish-green when ripe. Seeds numerous, rounded, irregular, about 5 mm long, embedded in foul-smelling pulp; embryo straight. Hybrids between S. ovata, S. alba, J. Smith and S. caseolaris (L.) A. Engler have been found in the estuary of brunei, where they grow together. Normally they are ecologically separated, S. ovata growing closest to the land-side. Diagnostic field characteristics for S. ovata are the broadly ovate leaves without mucro, the verruculose calyx surface, the appressed calyx lobes in fruit, the absence of petals, the white filaments and the rounded irregular seeds.

Its flowers are ephemeral and open at sunset, lasting for only one night; stamens fall off in the early morning. Bats and nectar-feeding birds are the pollinators. In Papua New Guinea, S. ovata flowers from March to October, and fruits are ripe in April-December. In Vietnam it flowers in March-April and bears mature fruits in June-July.

S. ovata is occasionally found on the banks of tidal creeks and rivers, on muddy soils inundated only by spring tides. Fruits float, so water is normal means of dispersal. It is found as individual trees, scattered among other mangrove species, such as Excoecaria agallocha L. S. ovata has never been found forming pure stands similar to S. alba and has also never been recorded from coral reefs.

Propagation is by seed.

Erosion control: It can be used to control erosion of tidal river banks. Ornamental: It is cultivated as an ornamental in some villages in coastal Sarawak. Other services: Because of their acidity they are sometimes used as substitutes for vinegar.

Fuel: The wood serves as firewood Tannin or dyestuff: Like other Sonneratia spp., the bark contains tannin, but in amounts too small for commercial exploitation. Food: The fruits are edible, though they taste very sour. Medicine: The fruit is also applied in poultices to relieve sprain. The fermented juice is believed to check haemorrhages.