Baliospermum
Blume
Herbs or shrubs, monoecious or dioecious. Leaves simple, alternate, sometimes shallowly
to deeply 3 - 5-lobed, penninerved; petioles biglandular at apex; stipules lanceolate, persistent
or caducous. Inflorescences leafy at the end of branches or axillary and leafless, sometimes
with long naked peduncle, bisexual or unisexual, crowded towards ends of branches, thyrsoid;bracts occasionally foliaceous. Male flowers: pedicellate; sepals (4 -) 5 (- 6), free or shortly
connate, imbricate, orbicular; petals absent; disc glands free or connate and shortly cupular;
stamens 12 - 25, free, the outer shorter than the inner; anthers 2-loculed, adnate to a broad
connective, basifixed, longitudinally and laterally dehiscent; pistillodes absent. Female flowers:
pedicellate; sepals 5 or 6 (- 10), sometimes accrescent and enlarging in fruit, imbricate; petals
absent; disc cupular; staminodes absent; ovary 3-locular, each 1-ovuled; styles 3, free or shortly
connate at base; stigmas mostly expanded and flabellate, bilobed or bifid, rarely capitate, recurved.
Fruits capsular, tricoccous, usually with persistent sepals; seeds carunculate, marbled;
endosperm fleshy; cotyledons broad.
India, S. China, S. & SE. Asia, Malesia, ca 12 species; 2 species in India.
Literature. CHAKRABARTY, T. & N. P. BALAKRISHNAN 1990 (1992). A revision of the genus Baliospermum Bl. (Euphorbiaceae) for the Indian subcontinent. Bull. Bot. Surv. India 32: 1 - 27, ff. 1 - 9.
Notes. This small genus shows a high degree of phenotypic variation, causing great difficulties for specific and infraspecific demarcation and classification.
Perry (Amer. J. Bot. 30: 527 - 543. 1943) reported the chromosome number of B. montanum to be 2n = 28 (from plants cultivated in Arnold Arboretum, USA). Sarkar et al. (Taxon 25: 649. 1976) recorded the chromosome number of the same species to be 2n = 22 (from materials obtained from wild plants of Uttar Pradesh, India). If both these counts are correct, the basic chromosome number of the genus may be x = 7 and 11.
Punt (Wentia 7: 1 - 116. 1962) studied the pollen grains of B. solanifolium (= B. montanum). The grains are inaperturate with characteristic “Crotonoid” pattern of polygonally arranged clavate sexinous processes. The diameter of the grain is about 43 øm and the diameter of the clavae is about 1.5 øm.
The genus shows wide range of ecological adaptations from sea level to 2000 m altitude in the E. Himalayas, in shaded primary evergreen forests to secondary deciduous forests, open forests, mixed forests and scrub jungles, from damp places near watercourses to dry wastelands and also as weeds in cultivated fields.
India, S. China, S. & SE. Asia, Malesia, ca 12 species; 2 species in India.
Literature. CHAKRABARTY, T. & N. P. BALAKRISHNAN 1990 (1992). A revision of the genus Baliospermum Bl. (Euphorbiaceae) for the Indian subcontinent. Bull. Bot. Surv. India 32: 1 - 27, ff. 1 - 9.
Notes. This small genus shows a high degree of phenotypic variation, causing great difficulties for specific and infraspecific demarcation and classification.
Perry (Amer. J. Bot. 30: 527 - 543. 1943) reported the chromosome number of B. montanum to be 2n = 28 (from plants cultivated in Arnold Arboretum, USA). Sarkar et al. (Taxon 25: 649. 1976) recorded the chromosome number of the same species to be 2n = 22 (from materials obtained from wild plants of Uttar Pradesh, India). If both these counts are correct, the basic chromosome number of the genus may be x = 7 and 11.
Punt (Wentia 7: 1 - 116. 1962) studied the pollen grains of B. solanifolium (= B. montanum). The grains are inaperturate with characteristic “Crotonoid” pattern of polygonally arranged clavate sexinous processes. The diameter of the grain is about 43 øm and the diameter of the clavae is about 1.5 øm.
The genus shows wide range of ecological adaptations from sea level to 2000 m altitude in the E. Himalayas, in shaded primary evergreen forests to secondary deciduous forests, open forests, mixed forests and scrub jungles, from damp places near watercourses to dry wastelands and also as weeds in cultivated fields.
KEY TO THE SPECIES
| 1 a. Plants dioecious; upper leaves not appreciably smaller than leaves of lower nodes; inflorescences leafless; male disc glands distinct; ovary glabrous or sparsely pubescent; fruits depressed, not intruded at apex, 5 - 8 x 9 - 10 mm | 1. Baliospermum calycinum |
| b. Plants mostly monoecious; upper leaves often appreciably smaller than leaves at lower nodes; inflorescences leafy; male disc glands connate into a cup; ovary tomentellous; fruits often turbinate-obovoid, intruded at apex, 8 - 10 x 11 - 13 mm | 2. Baliospermum solanifolium |
