Pithecellobium glabripetalum H.S.Irwin

  • Authority

    Irwin, Howard S. 1966. Contributions to the botany of Guiana. III. Leguminosae Mimosoideae. Mem. New York Bot. Gard. 15: 96-111.

  • Family

    Mimosaceae

  • Scientific Name

    Pithecellobium glabripetalum H.S.Irwin

  • Description

    Latin Diagnosis - Arbor 12-18 m alta 20-25 cm in diametro, ramulis petiolis rhachibus pedun-culisque minute pubescentibus vel glabrescentibus. Ramuli striati mox glabri. Glandula petioli plana ovata oblongave sessilis 1-2 mm longa circiter 0.5 mm lata; rhaches et axes pinnarum eglandulosae. Folia bipinnata; pinnae 6-10-jugae; foliola ex unica pinna 20-25-juga linaeri-lanceolata recta vel leviter falcata 5-7 mm longa 1.5-2.0 mm lata ad basem inaequilateralem unilateraliter truncata vel hastata apice obtusa margine revoluta supra glabra vel pilis paucis sparse vel modice pilosa. Flores umbellati; umbellae in paniculis terminalibus 10-15 cm longis dispositae; bracteae ca. 1 mm longae dense velutinae; pedunculi singuli vel fasciculati 1-2 cm longi; bracteolae orbiculares naviculares dense velutinar ca. 0.5 mm longae. Calyx 0.8-1.0 mm longus cupuliformis, limbo minute pubescente. Corolla campanulata, 2.5-3.0 mm longa ex toto glabra vel interdum limbo tan-tum ciliolato. Stamina ca. 1 mm longa, cum corolla aequante vel ea breviore. Ovarium pubescens 10-15-ovulatum, stigmatibus truncatis, stipiti ca. 0.4 mm longo. Fructus oblongi plani 8-10 mm longi ca. 2 mm lati glabri leviter lenticu-lati. Semina compressa late ovata 5-8 mm longa 4-5 mm lata.

  • Discussion

    This species has been confused with P. niopoides Spruce ex Benth. and P. polycephalum Benth. The former, known from Santarem, Para, and possibly from Dept. Loreto, Peru, has the following distinguishing characteristics: petiolar gland urceolate, substipitate; leaflets 25-25 pairs per pinna, linear 3-5 mm long, hardly more than 1 mm wide, glabrous or nearly so; flowers capitate; calyx ca. 0.7 mm long, finely but generally pubescent; corolla 2.0-2.5 mm long; stamens 5-7 mm long.

    The name P. polycephalum was originally applied to a Miers collection from Rio de Janeiro and, in my view, the application of the name had best be restricted to populations in southern Brazil. This species has the following characteristics to distinguish it from P. glabripetalum: petiolar gland urceolate, ovate, subsessile; rachis often with a smaller gland between the ultimate pinnae; leaflets oblong, 6-8 mm long, 2-3 mm wide, with 2-3 lateral nerves from the base; flowers sessile or subsessile; calyx 1.25-1.75 mm long, densely puberulent; corolla 2-3 mm long, densely puberulent; stamens 4-5 mm long.