Author: (Linnaeus) Roxburgh
Morphological description
Herb or undershrub up to 1 m high, foetid smelling, almost glabrous. Stipules setaceous, 10-15 mm, caducous.
Leaves (tora Senna branch FT28 ) paripinnate with 3 pairs of leaflets; petiole 1-4 cm; rachis 2-3 cm with a subulate, 2 mm long gland between the 2 lower pairs of leaflets (see drawing belowtora Senna fl/gl FT28 ). Leaflets shortly petiolulate, membranous, obovate, 2-5 by 1.5-2.5 cm, increasing in size distally; apex broadly rounded, base cuneate to rounded.
Inflorescence: Racemes axillary, short, 1- or 2(or 3)-flowered; bracts linear, acute; bracteoles absent;pedicels 5-10 mm, enlarging in fruit up to 15 mm.
Flower: Sepals 5, subequal, ovate, 5 by 2-4 mm (tora Senna fl/gl FT28 ). Petals 5, yellow, unequal, obovate, short-clawed with rounded apex, up to 10 by 6 mm. Stamens: 7 nearly equal, filaments 1.5-2 mm; anthers 3 larger, 4 smaller, 1.5-2.5 mm, opening by apical pores, the 3 larger abruptly rounded at apex; staminodes absent. Ovary densely pubescent; style glabrous; stigma truncate.
Pods linear, terete, more or less falcate, 10-15 by 0.5 cm.
Seeds 20-30, glossy, rhomboidal, 5 by 3 mm with an areole 1.5-2 mm wide covering much of the seed surface.
Distribution
Origin uncertain, but strictly palaeotropic in its occurrence.
Habitat
In the Malesian area it is common throughout at lower altitudes.
Uses
Young leaves are eaten locally, e. g. on Sumatra; on Timor it is believed to improve the soil. In India the seeds are roasted as a substitute for coffee; for further information on local use as medicinal plant, see Heyne (1950: 748); Burkill (1935: 481); Quisumbing (1951: 385).
Note
The present species is very closely related to Senna obtusifolia and is habitually similar to that species. S. obtusifolia is obviously rare and is often confused with S. tora. See also Note 1 under S. obtusifolia .