Large trees to small trees. Buttresses absent. Spines absent. Stilt roots absent. Bark gray, brown; not peeling in strips. Slash brown. Vertical stripes in the inner bark or wood absent. Odor absent. Exudate absent. Terminal buds not enclosed by leaves.
Complex hairs absent. Stinging hairs absent. Mature twig indumentum absent.
Leaves whorled; 5-20 per whorl; scale-like.
Inflorescences present; terminal; on an unbranched axis; specialized inflorescence units present, or absent; specialized inflorescence units heads; numerous and persistent inflorescence bracts absent. Flowers at least some flowers unisexual; with male and female flowers on the same plant, or with male and female flowers on different plants; not stalked; with the parts barely visible to the eye; round; with male or female parts not raised on a column. Hypanthium absent. Disk absent. Perianth absent. Stamens 1; filaments present; joined, or free of each other; all equal in size. Anthers 4 loculed; attached by the base; not awned; dehiscing by long slits. Ovary superior. Carpels joined; 2. Locules 2 (one aborts). Styles solitary. Stigmas 2 lobed; not distinctive. Fruit a samara; non-fleshy; multiple; splitting; not enclosed in, or sitting on, fleshy perianth parts; winged. Seeds 100 per fruit; barely visible; winged; uniform in cross-section; aril absent; non-endospermic.
Includes Ceuthostoma and Gymnostoma. Leaves resembling horsetails, inflorescence cone-like. Taxon images: casuarin.gif
Cite this publication as: Jarvie, J.K. and
Ermayanti (1996 onwards). `Tree Genera of Borneo - Descriptions and
Dallwitz (1980) and Dallwitz, Paine and Zurcher (1993) should also be cited.