Sterculia L.

Small to large trees; bark, whitish, warty, cracked or peeling off like paper. Leaves simple, digitate or palmately lobed, elliptic-lanceolate, oblong or obovate, tapering, acute, rounded, subcordate or cordate at base, acute, acuminate or abruptly acuminate at apex; petioles short to very long; stipules often caducous. Flowers unisexual, male or female by abortion in the same inflorescence, in axillary to terminal, erect or drooping panicles or racemes. Calyx 5-lobed, lobes broad or narrow, often conniving at tip in early stages, usually stellate-hairy outside, densely so inside. Corolla absent. Stamens 10 - 30, monadelphous, in a short or long column. Ovaries on long or short gynandrophore bearing sterile anthers in 5 groups at the base of ovary in female flowers; styles long, connate; stigmas as many as carpels, 5-lobed or fide Fruits coriaceous or woody follicles, 1 - many-seeded. Seeds sometimes arillate.

Tropics of both the hemispheres, predominantly in tropical Asia, ca 300 species; 15 in India.

Literature. DATTA, K. (1960) Some phytogeographical and economic aspects of the genus Sterculia (Sterculiaceae). Ind. For. 92: 510 - 516. TANTRA. I.G.M. (1976) A revision of the genus Sterculia in Malesia. Lembage Penelitian Hutan, Bogor, Laporian no. 102: 1 - 194.

KEY TO THE SPECIES

1a. Leaves digitate or palmately lobed

2

b. Leaves unlobed

5

2a. Leaves digitate

3

b. Leaves palmately lobed

4

3a. Leaflets up to 14 cm long; follicles almost glabrous

3. Sterculia foetida

b. Leaflets up to 27 cm long; follicles covered with dark brown urticating brittle hairs

14. Sterculia versicolor

4a. Leaves shallowly 5-lobed, entire, velvety beneath; follicles radiating

13. Sterculia urens

b. Leaves deeply 5 - 7-lobed, lobes 3-fid, villous beneath; follicles spreading

15. Sterculia villosa

5a. Calyx lobes broadly ovate, spreading

6

b. Calyx lobes linear or linear-Ianceolate, conniving at tip

9

6a. Leaves glabrous above, rusty tomentose beneath, cordate or subcordate at base

7

b. Leaves glabrous on both surfaces; rounded at base

11. Sterculia roxburghii

7a. Inflorescences few-branched; leaves subcordate at base

8

b. Inflorescences many-branched; leaves deeply cordate at base

9. Sterculia macrophylla

8a. Leaves charactaceous; flowers up to 1 cm long; calyx tapering to the pedicels in female flowers

4. Sterculia guttata

b. Leaves crustaceous; flowers up to 0.5 cm long; calyx folded at base in female flowers

2. Sterculia cordata

9a. Leaves rounded at base

10

b. Leaves acute at base

13

10a. Leaves glabrous above, pubescent beneath (except S. rubiginosa var. glabrescens)

11

b. Leaves glabrous on both sufaces

12

11a. Leaves up to 20 cm long; calyx globose, lobes short, connived at tips

10. Sterculia parviflora

b. Leaves up to 30 cm long; calyx widely campanulate, lobes long, somewhat spreading

12. Sterculia rubiginosa

12a. Inflorescences stellate-haity; calyx thick

1. Sterculia balanghas

b. Inflorescences sparsely pilose or almost glabrous; calyx membranous

8. Sterculia kingii

13a Leaves minutely adpressed hairy or scabrid on the nerves beneath; calyx teeth linear, stellate-hairy

14

b. Leaves glabrous on both surfaces; calyx teeth linear-Ianceolate, pilose

7. Sterculia khasiana

14a. Leaves minutely adpressed hairy beneath; androphore ca 5 mm long

5. Sterculia hamiltonii

b. Leaves scabrid on nerves beneath; androgynophore ca 1 mm long

6. Sterculia hyposticta

List of Lower Taxa