Author: (De Candolle) Degener
Morphological description
Herb with woody base or low shrub up to 1.5 m high, erect or decumbent; branches more or less densely greyish to yellowish pubescent.
Leaves with 10-30 pairs of leaflets; stipules persistent, linear, acute, 10-15 mm long; petioles 3-10 mm with a slightly elevated, discoid gland just below the lowest pair of leaflets (leschen Chamaecr fl/pgl 428821); rachis 5-12 cm, pubescent, canaliculate, i. e. with 2 parallel crests along the upper side; sometimes in dried specimens close together. Leaflets sessile, sensitive to touch (but less so than in C. mimosoides ), very unequal-sided, more or less falciform, 5-12 by 2-3 mm, glabrous, with ciliate margins; apex rounded oblique, mucronate (leschenault Chamaecr lf/gl FT30).
Inflorescence few-flowered, short, axillary or supra-axillary racemes; bracts and bracteoles like the stipules but smaller; pedicels pubescent, 7-10 mm long.
Flower: (leschen Chamaecr infl 428822)Petals yellow, unequal, lanceolate to obovate, 6-15 mm long, claw short. Stamens (4-)9-10; filaments very short; anthers 5-8 mm, opening by apical pores. Ovary woolly with long and short, thin hairs; style glabrous, recurved; stigma flat, ciliate.
Pods flat, strap-shaped, dehiscent, with long and short non-appressed hairs to nearly glabrous, 3-5 by 0.5 cm.
Seeds 10-15, black, smooth, flat, 4 by 3 mm.
Distribution
SE Asia (see Note 2), widespread in the Malesian area but much less common than Chamaecrista mimosoides.
Habitat & Ecology
In continental SE Asia this species is a mountain plant from 500-1600 m; in Java it is also found at lower altitudes and in New Guinea it is reported from Eucalyptus and Melaleuca forests at sea level, but also up to 1600 m in sandy places and secondary forest.
Notes
1. Larsen & Ding Hou (1996: 567) have maintained the old spelling of the name of Leschenault after advice received from the Mus. Nat. Hist. Nat. Paris.
2. Larsen & Ding Hou (1996: 567) regard this species as indigenous in SE Asia and are not able to follow Irwin & Barneby in joining it with Chamaecrista nicticans as a var. glabrata. There is, however, still work to be done with the C. mimosoides - leschenaultiana complex in tropical Asia; e. g. Verdcourt (1979: 48) is of the opinion that on New Guinea a mixture of indigenous and introduced elements occur and one collection from 1600 m (`area 6, Wamena') is an exceptionally robust plant with hairy fruits up to 6.5 by 0.6 cm. Also elsewhere special ecotypes occur; K. & S.S. Larsen (1980: 108) mentioned some very small forms from the Indo-Chinese area. Cassia leschenaultiana var. auricoma Grah. ex de Wit represents a part of a clinal variation that Larsen & Ding Hou (1996: 567) do not find necessary to recognize taxonomically.