Chamaecrista aristata

Shrubs or treelets up to 1.5-3 m with blackish trunks remotely & awkwardly branching upward, the ribbed annotinous branchlets, lf-stalks, and pedicels finely pilosulous with soft erect hairs to 0.2-0.4 mm, the coriaceous spine-tipped dull olivaceous or when young sublustrous, concolorous, coarsely venulose lfts either similarly pilosulous only near pulvinule dorsally or sometimes overall on both faces, the inflorescence often, by loss of some uppermost lvs, becoming pseudo-paniculate.

Stipules widely spreading or reflexed, lanceolate to narrowly ovate-acuminate, (1.5-)2.5-7 mm, at insertion 1-1.8 mm wide, prominently 3-5-nerved, deciduous with or shortly before the lf.

Lvs stiffly ascending (1.5—)2—7 cm, heteromorphic, those associated with fls commonly shorter and simpler than those below, all very shortly petiolate or subsessile, the expanded blade broadly ovate to oblong in outline; petiole including wrinkled pulvinus 1.5-3.5 mm, shallowly open-grooved; glands situated immediately below each pair of lfts, sessile, round or broadly elliptic, shallowly concave, thick-rimmed, 0.45-1.1 mm diam; rachis 0.5-4.7 cm, narrowly thick- margined and sulcate ventrally, the interfoliolar segments scarcely widened upward; lfts of some lower lvs 4-7, of upper lvs mostly 2-3 pairs, ascending face upward on insensitive broad but very short pulvinule, the blades obliquely ovate (1.5-) 1.7-3 x (0.8-)l-2 cm, abruptly acuminate and tipped with a stout stramineous or brownish vulnerant spinule 1.7—2.7 mm, at base cordate on proximal and more shallowly so or merely rounded on distal side, the margins thickened, crenulate, the stout subcentric midrib closely penninerved, the inner pair of lateral nerves almost as thick, incurved-ascending through the blade’s length to anastomosis with the marginal nerve, the outer laterals weaker and shorter, the secondary and close tertiary venulation bluntly prominulous on both faces.

Peduncles axillary to short upper lvs or arising from between pairs of stipules at a series of leafless nodes, mostly 3-7-fld, up to 14 mm long; pedicels flexuously ascending ±2-4 cm, bracteolate immediately beneath calyx; bracteoles subulate, 1.5-3 mm; buds slenderly ovoid-acuminate, puberulent at base; sepals subpetaloid, ovate-elliptic acute 10.5-13 mm; petals yellow, 4 obovate to broadly oblanceolate, shortly or obscurely clawed, of subequal length, 17-18 x 8.5-10 mm, the cucullus much longer, dimidiately ovate-reniform, ±25 x 12 mm; androecium 10-merous, not seen complete; ovary gray-strigulose; ovules 7-9.

Pod erect, linear or linear-oblanceolate in profile, slightly curved or straight, 3.5-5 x 0.6-0.8 cm, the castaneous coriaceous valves thinly minutely strigulose; seeds unknown.—Collections: 3.

Sandstone outcrops, 600-950 m, very local in the n. Sa. do Espinhaço of n.- centr. Minas Gerais, known precisely only from Sa. do Grão Mogol (near 16°30'S), where perhaps endemic.—Fl. VII-VIII.