Department of Botany, University of Karachi, Karachi.
Evergreen, glabrous trees or shrubs with or without conical respiratory roots (pneumatophores) or stilt roots. Branchlets swollen at the nodes. Leaves simple, opposite, rarely alternate, entire, leathery, mostly mucronate; stipules interpetiolar, conspicuous, caducous, leaving annular scar, rarely absent. Inflorescence axillary, mostly lax or congested biparous cymes or racemes of spikes or fascicled, rarely flowers solitary axillary. Flowers generally bisexual, rarely unisexual (plants then monoecious), actinomorphic, hypogynous to epigynous; bracteoles cupuliform or absent. Sepals 3-16, united into a tube, basally ± adnate to the ovary, lobes valvate, persistent. Petals as many as and alternating with sepals, free, often clawed, fleshy and conduplicate, mostly bifid and fringed, rarely persistent. Stamens 8 -numerous, free or epipetalous, anthers dorsifixed, introrse, 4-loculed rarely multilocellate, dehiscing lengthwise or by a ventral valve; staminodes in female flowers present. Ovary of (1-) 2-12, united carpels, inferior rarely perigynous or superior, (1-) 2-12-loculed, placentation axile, ovules anatropous, pendulous, usually 2 in each locule; style with simple or lobed stigma. Fruit 1-seeded, unilocular, mostly an indehiscent berry or drupe rarely septicidally dehiscent, 2-4-chambered capsule. Seeds with or without aril, endospermic or not, often viviparous; embryo straight or curved with macropodous radicle.
A family of 16 genera and c. 120 species, distributed in tropical areas, mainly of the Old World and forming part of the mangrove vegetation of muddy coasts. Represented in Pakistan coastal swamps by 3 genera and 5 species. The family is poorly known in our area and further collecting is needed.
Acknowledgements: We are grateful to the United States Department of Agriculture for financing this research under P.L. 480 with the coordination of Pakistan Agricultural Research Council, Islamabad. Thanks are also due to Messers B.L. Burtt, I.C. Hedge & Miss J. Lammond of the Royal Botanic Gardens, Edinburgh, for their helpful suggestions.