Cleistanthus Hook.f. ex Planch.

Monoecious shrubs or trees, glabrous or pubescent with simple hairs. Leaves simple, alternate, usually bifarious, symmetric, petiolate, stipulate, entire, often glossy above and glaucous beneath, penninerved. Inflorescences axillary, fasciculate-glomerulate, borne on main leafy branches or sometimes on special leafless or small-leaved branchlets; bracts up to 2 mm long. Male flowers: sessile or shortly pedicelled, calyx tube shortly obconical, segments (sepals) 5, valvate; petals 5, free, alternate to sepals; disc annular or shortly cupular; stamens 5; filaments connate below into a column, free and spreading above; anthers longitudinally dehiscent; pistillode small, at the apex of the column, trifid or trilobed. Female flowers: sessile or sometimes pedicellate, occasionally with a gynophore; calyx and petals as in male; disc annular, cupular or urceolate; ovary often enclosed by disc, 3-locular; locules biovulate; ovules anatropous; styles 3, usually shortly connate below into a column, simple or bifid above. Fruits capsular, sessile or shortly pedicellate, subglobose or depressed, tricoccous with 3 bivalved cocci (rarely tetralocular); seeds trigonous, exarillate and ecarunculate; cotyledons thin and flat or thick and fleshy; endosperm copious or sparse.

Old World tropics, from Africa to Asia, Australia and Melanesia, ca 148 species; 7 species in India.

Literature. CHAKRABARTY, T., GANGOPADHYAY, M. & N. P. BALAKRISHNAN (2002). The genus Cleistanthus Hook.f. ex Planch. (Euphorbiaceae) in the Indian subcontinent. J. Econ. Taxon. Bot. 26: 331 - 345.

KEY TO THE SPECIES

1 a. Leaves rounded, retuse or apiculate at apex; fruits 18 - 22 x 17 - 22 mm

3. Cleistanthus collinus

b. Leaves acuminate or caudate at apex; fruits 3 - 12 x 4 - 15 mm

2

2 a. Fruits stipitate (with a gynophore); leaves densely and finely appressed golden brown, coppery or silvery sericeous beneath

5. Cleistanthus myrianthus

b. Fruits not stipitate; leaves not sericeous beneath, glabrous or pilose or hirsute on the nerves or tomentose beneath

3

3 a. Stipules 5 - 10 mm long

4

b. Stipules 1- 5 mm long

6

4 a. Leaves scattered pilose or hirsute on major nerves beneath; inflorescences arising on main leafy branchlets (S. India)

4. Cleistanthus malabaricus

b. Leaves glabrous or sparsely pilose on midrib beneath; inflorescences arising on special smallleaved branchlets (Andaman and Nicobar Islands)

5

5 a. Branchlets and petioles glabrous; leaves coriaceous, apical cauda 5 – 10 mm long; lateral nerves 5 – 7 per side; fruits glabrous, sessile

1. Cleistanthus andamanicus

b. Branchlets and petioles pubescent; leaves chartaceous to subcoriaceous; apical cauda 10 – 30 mm long; lateral nerves 7 – 10 per side; fruits puberulous, shortly pedicellate

2. Cleistanthus balakrishnanii

6 a. Inflorescences borne on special small leaved or leafless branchlets; fruits depressed, 5 - 12 x 10 - 15 mm, sessile

6. Cleistanthus patulus

b. Inflorescences borne on main leafy branches; fruits subglobose, 3 - 5 x 4 - 6 mm, pedicellate (pedicels 1.5 - 2 mm long)

7. Cleistanthus travancorensis

List of Lower Taxa