Breynia
J.R.Forst. & G.Forst., nom. cons.
Shrubs or trees, occasionally scandent or climbing, monoecious, evergreen, glabrous or
rarely pubescent. Leaves alternate or distichous, entire and sometimes reflexed or revolute
along margins, penninerved; petioles short; stipules short. Male inflorescences usually in the
lower leaf-axils, fascicled, few-flowered. Flowers: pedicellate; calyx obconical, turbinate or
sometimes cupular, 6-fid at apex with inflexed and imbricate lobes; petals and disc absent;
stamens 3; filaments united in a column; anthers adnate to the column, linear, 2-loculed,
longitudinally dehiscent. Female inflorescences usually in the upper leaf-axils, solitary or in
pairs. Flowers: pedicellate, calyx obconical, cupular or patelliform, shallowly or deeply 6-lobed,
often accrescent in fruit; petals and disc absent; ovary 3-locular; locules biovulate; styles 3,
conspicuous and bifid or minute and simple. Fruits capsular, somewhat fleshy, 3-locular, unlobed,
red when ripe, tardily dehiscent; seeds trigonous, with rounded backs; seed coat fleshy;
endosperm copious; cotyledons broader than and 1 - 2 times larger than radicle.
Sri Lanka and India to China, SE. Asia, Malesia, Australia and New Caledonia, ca 25 species; 3 species in India.
Literature. CHAKRABARTY, T & M. GANGOPADHYAY (1996). The genus Breynia (Euphorbiaceae) in the Indian subcontinent. J. Econ. Taxon. Bot. 20: 501 - 512.
Notes. The haploid chromosome numbers in B. retusa and B. vitis-idaea are reported to be n = 26 (Dutta, Taxon 16: 341 - 350. 1967; Mehra & Hans, Taxon. 18: 310 - 315. 1969 and Gill & Bedi, Taxon 28: 402. 1979).
The pollen grains are oblate spheroidal to oblate, intectate, reticulate; lumina 1 - 2 ìm. Aperture characterised by the large number of colpi and the double circular colpi transversalis (Punt, Wentia 7: 1 - 116. 1962).
Sri Lanka and India to China, SE. Asia, Malesia, Australia and New Caledonia, ca 25 species; 3 species in India.
Literature. CHAKRABARTY, T & M. GANGOPADHYAY (1996). The genus Breynia (Euphorbiaceae) in the Indian subcontinent. J. Econ. Taxon. Bot. 20: 501 - 512.
Notes. The haploid chromosome numbers in B. retusa and B. vitis-idaea are reported to be n = 26 (Dutta, Taxon 16: 341 - 350. 1967; Mehra & Hans, Taxon. 18: 310 - 315. 1969 and Gill & Bedi, Taxon 28: 402. 1979).
The pollen grains are oblate spheroidal to oblate, intectate, reticulate; lumina 1 - 2 ìm. Aperture characterised by the large number of colpi and the double circular colpi transversalis (Punt, Wentia 7: 1 - 116. 1962).
KEY TO THE SPECIES
| 1a. Styles prominent, 1 - 2 mm long, bifid; fruiting calyx greatly enlarged, 6 - 12 mm in diam. | 2. Breynia retusa |
| b. Styles almost obsolete, up to 0.5 mm long, simple, subulate, triangular or deltoid; fruiting calyx not much enlarged, 2 - 5 mm in diam. | 2 |
| 2a. Plants usually scandent or climbing; leaves coriaceous, glaucous beneath, conspicuously reflexed or revolute along margins; fruits 6 - 10 mm in diam. | 1. Breynia racemosa |
| b. Plants arborescent; leaves membranous or often chartaceous, not or scarcely glaucous beneath, flat along margins; fruits 4 - 6 mm in diam. | 3. Breynia vitis-idaea |
