Pithecolobium elegans sensu Ducke, 1949: 38.

Trees with smooth rusty-brown, yellowish, or pale orange trunk, attaining 30-45 m but flowering when 8 m or less, closely akin to and resembling B. pedicellaris in habit, indumentum, stipules, foliage, and lf-nectaries, but with larger fls and fruit different in venation of the valves. Lf-formula x-xv/20-31; lf-stks 8-18 cm, the petiole ±2.5—4.5 cm, the longer interpinnal segments ±8-14 mm; first petiolar nectary either near or well above midpetiole; rachis of longer pinnae 5-10 cm, the longer interfoliolar segments 1.7-3 mm; longer lfts 6—9.5 x 1.7—3 mm, 2.4—3.4 times as long as wide, when dried dull on upper face and sometimes thinly puberulent along midrib, or thinly so overall, beneath less obviously papillate than those of B. pedicellaris. PERIPHERAL FLS: pedicels 6-10 (ex char.: -20) mm; calyx 4-5 x 2-3.5 mm, the teeth ±1-1.5 mm; corolla 8-10 mm, the lobes 2.5-3.5 x 1.6-2 mm; androecium 25-35-merous, ±3-3.5 cm, the stemonozone 1.3-2 mm, the tube 3-5.5 mm, filaments green or white distally; ovary truncate, densely minutely golden-strigulose overall; style long-exserted. Pods (not seen fully ripe) almost of B. pedicellaris, 9-15 x 2.4-3 cm, 12-23-ovulate, the glabrous valves coarsely transverse-venulose, the major fibers separated from each other by intervals much greater than their own diam, freely branched; seeds 7x4 mm in broad view, oblong, vivid green within, whitish or pink without, the pleurogram almost complete.

In primary rain forest on terra firme, below 350 m, discontinuously scattered between the equator and 11°S through the basins of ríos Madeira, Tapajoz, Jarí, and Tocantins in Hylaean Brazil, SW on the upper Río Acre just into Bolivia (Pando); distantly disjunct in Costa Rica (Limón) and Nicaragua. — Map 6. — Fl. V-VII(-?). — Toco bianco (Pando), mapuchiquí, mapuxiqui vermelho (Amazonas).