Caesalpinia digyna

Author: Rottl.

Morphological description (digyna Caesalpinia compl FT19 )
Liana , scandent shrub , or small tree , up to 10 m, young parts densely rusty-brown hairy; branchlets armed with recurved prickles (4–5 mm long). Stipules subulate, to 3 mm long, slightly hairy, caducous.

Leaves: rachis 17–23 cm; pinnae 8–13 pairs, 4–5 cm, unarmed. Leaflets opposite, 7–12 pairs per pinna, subsessile, membranous, oblong or ovate-oblong, 5–11 by 2.5–4.5 mm, appressed short-hairy on both surfaces, base oblique-truncate, apex truncate or notched, margins parallel, lateral nerves obscure.

Inflorescences axillary and terminal, paniculate, 30–40 cm long, the rachis glabrous or hairy, with a few prickles in the basal part; bracts somewhat boat-shaped, 4 by 0.4 mm, hairy; pedicels spreading, slender, 15–25 mm, glabrous or with a few hairs, articulated at the base (digyna Caesalpinia infl FT19 ).

Flower buds glabrous (digyna Caesalpinia details FT19). Hypanthium 1–2 mm deep and 6–7 mm wide. Sepals 3–8 by 2–5 mm. Petals 5–8 by 3–8 mm, shortly clawed (claw up to 2 mm long). Stamens slightly exserted; ¾laments c. 12 mm; anthers 1.5 mm, glabrous or with a few hairs. Ovary 3–4 mm long, glabrous or silky-hairy along the sutures, 2–4-ovuled; style 6–8 mm, glabrous; stigma 0.3 mm in diameter, short-hairy along the margin.

Pods (with hypanthium persistent, 1–2 mm deep and 7 mm wide) indehiscent, elliptic-oblong, 3–5 by 2.5–2 cm, glabrous, base rounded, apex obtuse, short-beaked, often constricted between the seeds, 1–3- (or 4-) seeded.

Seeds subglobose, 10–12 mm in diam, dark brown.

India, Nepal, Sri Lanka, Burma, Laos, Cambodia, Vietnam, Thailand. In Malesia: Sumatra (Palembang), NW Malay Peninsula, Java (C and E, also Madura and Kangean Is.), Lesser Sunda Islands (Bali).

Habitat & Ecology
Dry plains or hills, savannahs, scrubland, forest fringes, up to 250 m altitude. Periodicity for flowering and fruiting not found.

The pods are rich in tannins and are used for tanning. See Boonkerd et al., 1991: 57. The seeds appear nutritious (Burkill, 1935: 387).