Author: (Willdenow) Irwin & Barneby
Morphological description
pendula Senna Colladon f12
Shrub 1-3(-4) m high, indumentum varying from almost glabrous to more or less densely pubescent. Stipules linear lanceolate, 2-10 mm long, very early caducous.
Leaves paripinnate with 3-6 pairs of leaflets; petiole 1.5-4 cm, sulcate; rachis 3-6 cm with a subsessile, ovoid to obovoid gland between the lowest pair of leaflets, more rarely between the second pair or between all but the distal; petiolules c. 1 mm, pubescent. Leaflets obovate to oblanceolate, unequal-sided, 2-5 by 1-3 cm; upper surface glabrous, lower more or less sparsely pubescent; base unequal-sided, more or less cuneate.
Inflorescence: Racemes axillary, usually few-flowered, 3-10 cm long including the 3 cm long peduncle; bracts similar to the stipules; bracteoles absent;pedicels 15-30 mm long.
Flower: Sepals glabrous, ovate to oblong, broadly rounded, c. 10 mm long. Petals 5, golden to orange-yellow, obovate, 15-25 mm long, subsessile. Stamens 10: 2 long with filaments 11-12 mm, anthers curved, c. 10 mm, opening by apical pores; 1 shorter with filament 4-5 mm and a similar but narrower anther; 4 short ones with filaments 1-2 mm and straight anthers 4-6 mm; 3 staminodes with 1-2 mm filament and anthers transformed to a trapeziform blade; all yellow; filaments of all stamens straight. Ovary sessile, more or less sparsely puberulous; style filiform, incurved or hooked distally; stigma inconspicuous.
Pods pendulous, terete, short-stiped (sterile at base and looking long-stiped), stipe 2-5 mm, usually glabrous, 8-15 cm long, 5 mm diameter.
Seeds dark brown, flattened, ovoid, 4-6 mm, separated by septa.
Distribution
Tropical and subtropical S America; elsewhere occurring as a weed; very rare in Malesia .
Note
This is an extremely variable species in which Irwin & Barneby (1982: 378) recognize 19 varieties. However, most of these are not clearly separated. The alsmost glabrous plants collected in Java are probably best placed in var. glabrata (Vogel) Irwin & Barneby, while the others may approach var. advena (Vogel) Irwin & Barneby.