Monographs Details: Abarema microcalyx (Spruce ex Benth.) Barneby & J.W.Grimes var. microcalyx
Authors:Rupert C. Barneby
Authority: Barneby, Rupert C. & Grimes, James W. 1996. Silk tree, guanacaste, monkey's earring: a generic system for the synandrous Mimosaceae of the Americas. Part I. Abarema, Albizia, and allies. Mem. New York Bot. Gard. 74: 1-292.
Description:Variety Description - Characters as given in key to varieties [Key: "pod relatively narrow and of thin texture, 11-16 mm wide at the seeds, and there in cross-section at most 0.6 mm thick; exterior suture of pod undulately constricted."]; longest pedicels ±0.6-1.2 mm; pods 11-16 mm wide, the relatively thin valves coarsely venulose externally, the pitchlike mesocarp in cross section (dry) 0.2-0.5 mm thick.

Distribution and Ecology - In moist forest on terra firme, commonly on sandy, sometimes clayey soils, below 160 m, apparently not rare on and near the Orinoco-Negro divide in T. F. Amazonas, Venezuela, thence extending S along the Río Negro into NW state of Amazonas, Brazil (S. Gabriel da Cachoeira; lower Uaupés valley) and W just into SE Com. Vaupés, Colombia. — Map 13. — Fl. X—III. [Key] "Dispersed on upper rios Negro and Uaupés in NW Amazonas, Brazil, and thence into adjacent Colombia and to the Orinoco divide in T.F. Amazonas, Venezuela;"

Local Names and Uses - Maripa, palo de jabón (Venezuela), the bark furnishes a detergent used in washing.

Distribution:Amazonas Venezuela South America| Amazonas Brazil South America| Vaupés Colombia South America|

Common Names:Maripa, palo de jabón