Doryxylon Zoll.

Trees or large shrubs, monoecious, evergreen, with dense sessile and peduncled stellate or lepidote hairs; axillary buds sometimes modified into thorns. Leaves spirally arranged, simple, white tomentose beneath, long-petiolate, subpeltate or epeltate at base, entire or distantly dentate; stipules triangular, hairy, caducous. Inflorescences axillary or terminal, bracteate spiciform racemes, seldom branching; rachis densely hairy. Male flowers: in fascicles of 3 - 5, in axils of bracts; calyx 3 - 5-partite; lobes valvate; petals 4, 5 or 10, short, imbricate or valvate; disc absent or rarely very small, obsolete and dentate; stamens ca 75 to numerous, arranged on convex hairy receptacle; filaments free, erect; anthers oblong, basi-dorsifixed, longitudinally dehiscing; pistillode absent. Female flowers: solitary in each cluster of male flowers; calyx 5 - 6- partite; lobes shortly imbricate; petals absent or rudimentary; disc small, annular; ovary 3- loculed; ovule one in each locule; styles 3, connate at base, entire or slightly bifid. Fruits 3- loculed capsule with 3 bivalved cocci, septicidal from apex to base and loculicidal from base to apex, thin-walled; seeds usually 3, rarely 2, subglobose, angular, large, smooth or pitted-foveolate outside, with fleshy sarcotesta and fibrous endotesta; embryo straight; cotyledons flat; endosperm copious.

NE. India, Myanmar, Thailand, Vietnam, Malaysia, Java, Sumatra and Philippines, 2 species; one in India.

Notes. The genera Sumbavia Baillon and Sumbaviopsis J.J. Smith are included in this genus. The generic name Doryxylon Zollinger has priority over them.

Literature. BALAKRISHNAN, N. P. (1967). Studies in Indian Euphorbiaceae II. The genus Doryxylon Zoll. Bull. Bot. Surv. India 9: 56 - 58, ff. 1 - 7. VAN WELZEN, P. (1999). Revision and phylogeny of subtribes Chrozophorinae and Doryxylinae (Euphorbiaceae) in Malesia and Thailand. Blumea 44: 411 – 436.

List of Lower Taxa