Ceratopetalum
Content
Description
Trees to canopy size (in Australia also shrubs).
Leaves opposite and decussate, trifoliolate (occasionally bifoliolate) or (in Australia) unifoliolate, with nerves and venation prominent on both surfaces;
Stipules interpetiolar, one pair per node, resinous, early caducous.
Inflorescences terminal and/or axillary, proximal branching opposite and decussate and ultimate branching cymose, ± corymbose in shape, many-flowered, with small caducous bracts.
Flowers 4-6-merous (except gynoecium), bisexual, with short pedicel gradually widening into discoid receptacle.
Sepals valvate, ± reduplicate, coriaceous, substantially enlarged and woody in fruit.
Petals in one Australian species 3-5-furcate, in all others absent.
Stamens with subulate filaments and cordate anthers.
Ovary semi-inferior, syncarpous, 2-carpellate, superior part conical;
Fruit indehiscent, a pseudosamara, surrounded by radiating enlarged woody sepals;
Distribution
Asia-Tropical: New Guinea present, NE Australia present, New Britain present, SE Australia present
8 species, 2 in SE Australia and 6 in NE Australia (including 2 as yet undescribed), one of which extends to Malesia: New Guinea and New Britain.
Ecology
Most species are typically tall rain forest trees but one of the Australian species (C. gummiferum Sm.) is a shrub to small tree, usually found in drier sclerophyll forest and heathland on sandstone, and in NE Australia some species occur and (R.W. Barnes, pers. comm.).
Uses
The genus has some importance as a source of timber and in horticulture. A summary for Malesia is given by Dickison (). In New Guinea, C. succirubrum is of local commercial im-portance though supplies are limited. It is widely used in furniture and cabinet work, house building, general turnery and carving, and it is also suitable for plywood. The timber of C. apetalum D.Don from Australia is highly valued for furniture and less so as a general building hardwood. It is also used as outer veneer in high quality plywood for furniture. It was previously used in coach building, hence the Australian name ‘Coachwood’. In C. gummiferum, the calyx lobes are bright red and contrast with the deep green foliage, and the species is valued as Christmas decoration, hence the name ‘Christmas Bush’ (see ).