Trees, shrubs, lianas or scramblers, usually armed with spines or prickles, rarely unarmed. Leaves alternate, rarely opposite (C. oppositifolia), bipinnate, usually paripinnate, rarely imparipinnate, petioled; pinnae opposite; rachides on the underside often with prickles. Stipules present or absent, minute to large and leafy, caducous or persistent. Inflorescences axillary and then often serial, and/or terminal, racemose or paniculate; bracts mostly caducous; bracteoles absent. Flowers usually bisexual, sometimes unisexual, zygomorphic, often all parts punctate (secretory cavities), pedicelled. Sepals 5, usually united at the base, unequal, the lower one usually cucullate, longer than the others and clasping them, often reflexed during anthesis. Petals 5, unequal, often spathulate, the limb usually (sub)orbicular or oblong, sometimes contracted towards the basal part into a narrow claw; the upper one (standard) mostly deviating from others in both shape and size, sometimes with a liguli- form appendage. Stamens 10, free, equal or alternately longer or shorter; filaments usually hairy at the lower half or at the base; anthers dorsifixed, glabrous or rarely villose, laterally longitudinally dehiscent. Seeds orbicular or globose, ellipsoid or reni- form, sometimes flattened, often smooth, usually exalbuminous.
Asia-Tropical: Pantropical: present Solomon Islands: present
Pantropical, c. 100 species; all over Malesia with 18 indigenous species, 1 in Solomon Islands but not yet found in Malesia proper (C. solomonensis), 3 introduced and now wide-spread (C. coriacea, C. pulcherrima, C. sappan) and 2 occasionally cultivated, not treated here: C. spicara Dalz. and C. spinosa (Molina) Kuntze.
The present treatment of Caesalpinia is chiefly based on the comprehensive revision published by Hattink .
L., Gen. Pl, ed. 5. 1754: 179
Prain - in J. As. Soc. Beng. 1897: 130
Watson & Dallwitz, Gen. Leg.-Caesalp. 1983: 16.
L., Gen. Pl, ed. 5. 1754: 178
Miq. - in Fl. Ind. Bat. 1855: 113.
Polhill & Vidal - in Polhill & Raven, Adv. Leg. Syst. 1. 1981: 93
Backer & Bakh. f. - in Fl. Java. 1964: 546.
Hattink - in Reinwardtia. 1974: 9
L., Gen. Pl, ed. 5. 1754: 178.