Shrubs or small trees, dioecious or rarely monoecious, very rarely scandent shrubs,
nearly glabrous. Leaves simple, alternate, short petioled; stipules caducous. Inflorescences
unisexual or rarely bisexual, cymose, axillary and terminal, solitary, paired or 3-flowered (umbellate),
shortly racemiform or thyrsoid, often tending towards dichasial branching. Male flowers:
bracteate, pedicellate; calyx cupular, 5-lobed, imbricate; petals 5, imbricate, white; disc of 5 free glands; stamens biseriate, 8 - 16, the outer usually free or sometimes partially or shortly connate;
the inner united into a column; anthers 2-loculed, with broad connectives, dorsifixed or basifixed
(in the same flower), longitudinally dehiscent; pistillode absent. Female flowers: bracteate,
pedicellate; sepals 5, free or shortly connate, imbricate, often gland-pitted or emarginate at apex,
accrescent in fruit; petals 4 or 5, imbricate, white, caducous; disc glands connate in a ring or
shortly cupular-annular; staminodes absent; ovary 3-locular; locules 1-ovuled; styles 3, connate
at base or free, bifid. Fruits capsular, tricoccous, evanescently pubescent or glabrous, woody,
splitting into bivalved parts leaving a central column; seeds trigonous with a broad convex
back; endosperm fleshy; cotyledons flat, broad.
Tropical South India, Andaman & Nicobar Islands, Sri Lanka, Indo-china, Hainan, West
Malesia, New Guinea and Lesser Sunda Islands, ca 15 species; 4 species in India.
Literature.
CHAKRABARTY, T. & N. P. BALAKRISHNAN (1990). Genus Dimorphocalyx
Thw. (Euphorbiaceae) in India. Proc. Indian Acad. Sci. (Pl. Sci.) 100: 285 - 299, ff. 1 - 4.
KEY TO THE SPECIES
1 a. Plants monoecious; inflorescences bisexual (endemic to Andaman Islands)
b. Inflorescences not dichasial; stamens 10 - 16; ovary pubescent; styles 3 - 7 mm long, connate
below into a column; fruits evanescently pubescent
3
3 a. Branchlets, petioles, peduncles and pedicels glabrous; leaves elliptic to lanceolate, rounded,
obtuse to acute at base, acuminate at apex; female pedicels 3 - 10 mm long; sepals glabrous;
stamens 10 - 16, filaments of outer stamens free almost up to base
b. Branchlets, petioles, peduncles and pedicels pubescent; leaves obovate to oblanceolate, attenuate
at base, obtuse to subacute at apex; female pedicels up to 2 mm long; sepals appressed-pilose;
stamens 16 - 20, filaments of outer stamens shortly connate at base, free above
