Botanical Survey of India | Flora of India

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Deciduous or evergreen, armed or unarmed, shrubs or small trees, rarely scandent. Leaves alternate, subopposite or fascicled, petiolate, penninerves, entire or dentate; stipules minute, free, persistent or deciduous. Inflorescence axillary, solitary cymes or fascicles, rarely panicles or thyrses. Flowers 5- or 4-merous, bisexual or polygamo-dioecious. Calyx lobes 4-5, triangular-ovate, erect or spreading; tube urceolate. Petals 4-5 or absent, inserted on the margin of calyx tube, cucullate or flat, shortly clawed. Stamens 4-5; filaments very short; anthers dehiscing longitudinally. Disc thin, tilling the calyx tube. Ovary (2-) 3 or 4-celled, ovoid; styles 3-4 -cleft, rarely 2-cleft about half the length; stigma obtuse, papillose. Drupes with 2-4, free, 1-seeded stones, globose, encircled at base by calyx tube; pyrenes horny or cartilaginous, indehiscent or dehiscing inwardly. Seeds obovate; testa membranous or crustaceous, smooth or furrowed on the back; raphe dorsal, ventral or lateral; albumen fleshy; cotyledons flat or with recurved margins.

America, Europe, Asia, often rare in tropics; ca 150 species, 11 in India.

Notes. Most of the Indian species are confined to the Himalayas except R. purandharensis and R. wightii. which are confined to peninsular India.

Indian species are found in wooded or open forests in Himalaya and Western Ghats, usually at altitudes ranging between 600 to 3000 m.



KEY TO THE SPECIES


1a. Erect shrubs or trees, sometimes rambling 2
b. Prostrate shrubs 10
2a. Plants unarmed 3
b. Plants armed (unarmed in R. procumbens) 8
3a. Leaves pubescent or tomentose 4
b. Leaves glabrous 6
4a. Petals absent; fruits surrounded at base only by rim of the calyx 9. Rhamnus purpurea
b. Petals present; fruits surrounded at base by persistent, 5-lobed calyx 5
5a. Leaves serrate; calyx keeled within; style cleft nearly-down to the base 8. Rhamnus purandharensis
b. Leaves crenate; calyx not keeled; style cleft only at apex 10. Rhamnus triqueter
6a. Leaves distantly crenate 3. Rhamnus nepalensis
b. Leaves closely serrate 7
7a. Flowers ca 6 mm across; petals obtuse and apiculate; disc 5-lobed; ovary 3-4-loculed; style 3-4 cleft 11. Rhamnus wightii
b. Flowers up to 3.5 mm across; petals retuse; disc unlobed; ovary 2-loculed; Style 2-cleft 1. Rhamnus collettii
8a. Flowers 5-merous 4. Rhamnus pentapomica
b. Flowers 4-merous 9
9a. Leaves glabrous, serrulate; petals present 2. Rhamnus dahuricus
b. Leaves pubescent, entire or faintly crenate; petals absent 5. Rhamnus persica
10a. Unarmed; leaves alternate, sharply serrate with acute apex; petals absent 6. Rhamnus procumbens
b. Armed; leaves fascicled, distinctly crenate, with obtuse apex; petals present 7. Rhamnus prostrata


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