Trees or shrubs, evergreen (Mal. spp.); leaf-scars large. Leaves crowded towards the end of the shoots, spiral, simple, exstipulate, serrate with glandular teeth, often with an apical gland, more rarely entire; nerves a little decurrent along the midrib, both midrib and nerves ± impressed above, ± prominent beneath. Indumentum of branchlets, leaves and inflorescences consisting of simple, and/or long, fascicled and ± patent, and/or minor, ± depressed stellate hairs. Flowers bisexual, regular, 5(-6)-merous. Inflorescences sometimes simple solitary terminal racemes, but mostly consisting of a terminal raceme and several lower approximate racemes, each of the latter from the axil of a ± reduced or caducous leaf, thus forming together a panicle-, fascicle- or umbel-like inflorescence; bracts mostly caducous during anthesis, rarely subpersistent. Calyx lobes 5 (-6), persistent, quincuncially imbricate, united at the base only. Petals 5 (-6), generally free, sometimes cohering to some degree, alternate with the calyx lobes, rather early caducous, generally sweet-scented. Stamens 10(—12) in 2 whorls of 5(-6), the outer whorl opposite the petals, the inner one opposite the calyx lobes; filaments adnate to the corolla at the extreme base; anthers dorsifixed, overturned outwards in bud, erect in anthesis, introrse, upper part of cells ± divergent, opening with apical, slitlike pores; pollen grains single, tricolporate, psilate. Ovary superior, 3-celled, with axile placentation; ovules ∞, small, anatropous; style simple, mostly shortly, very rarely hardly divided into three apical lobes, sometimes more deeply so and trifid, each lobe stigmatic at the top. Fruit a 3-valved, loculicidal capsule, the septae of which become loose from the persistent central axis, subtended or ± enclosed at maturity by the persistent calyx. Seeds ∞, small, subovoid to irregularly angular or subtrigonous, with a foveolate-reticulate testa (all Mal. spp.). Endosperm fleshy. Embryo cylindrical. Distribution. A small, monogeneric family in the Ericales, of (sub)tropical Asiatic-Malesian, and temperate and tropical American distribution, and with 1 sp. in Macaronesia (Madeira, and formerly in Teneriffe).
|Journal||Flora Malesiana - Series 1, Spermatophyta|
|Rights||Released under the CC-BY 4.0 ("Attribution") License|
Sleumer, H. (1972). Clethraceae. Flora Malesiana - Series 1, Spermatophyta, 7(1), 139–150.