Diffuse shrubs and bushy trees 1.5-10 m, closely resembling Ch. tenuiflorum but more commonly armed than not, the thorns 0.5-2 cm, and the foliage glabrous, and the fls heteromorphic; perules 1.5-4.5 mm. Stipules linear 2-2.5 x 0.25-0.33 mm, quickly deciduous. Lf-formula (ii—)iii—vi/6—8(—9); lf-stks 2.5-5.5 cm, the longer interpinnal segments 7-16 mm; rachis of longer pinnae 2.5—4.5 cm, the longer interfoliolar segments 4-7 mm; petiolar nectaries obconic or tub-shaped, the first situated well below midpetiole, sometimes close to lf-pulvinus, 0.4-0.7 mm diam, 0.3-0.6 mm tall; lfts of Ch. tenuiflorum, the larger ones 8-14 x 3.2-5.5 mm, 2.2-3 times as long as wide. Peduncles 8-16 mm; fls heteromorphic, the peripheral ones either sessile or the outermost raised on a pedicel to 0.7 mm, the terminal one sessile on a receptacular pedestal to 1 mm; perianth of Ch. tenuiflorum, the calyx 1.8-2.3 mm, the corolla 5.5-6.5 mm; filaments ±18, to 14—17 mm long, the tube in peripheral fls ±3—4.5 mm, shorter than the corolla, that of the terminal fl well exserted. Pods of Ch. tenuiflorum, the sutures 1-1.5 mm wide, the stiffly leathery or finally ligneous valves 11-15 mm wide, coiled into a compressed or more open and springlike helix 2.5-3 mm diam; seeds of Ch. tenuiflorum but the pleurogram incomplete.

In restinga along the ocean front and in thickets on sandy soils of the coastal plain below 70 m, apparently endemic to the coast of Rio de Janeiro state and Guanabara, from the city and bay eastward to cabos Frio and dos Buzios. — Map 40. — Fl. IX-I. — Yacarí (Glaziou).

Chloroleucon tortum resembles Ch. tenuiflorum in the helicoid pod but has the smooth bark and branches of Ch. glazioui, vicariant inland, of which it may be an ecologically specialized derivative adapted to littoral habitats.