Pterolobium borneense

Author: Merr.

Morphological description
Scandent shrub or liana .

Leaves : petiole and main rachis up to c. 20 cm long, puberulous; pinnae c. 10 pairs, petiole and rachis, 4-6 cm long, puberulous. Leaflets 10-14 pairs per pinna, oblong, c. 10 by 3 mm, entire, glabrous, nerves and veins invisible.

Inflorescences 25 cm long, rachis and branchlets pubescent, densely flowered; pedicels 2-3 mm, sparsely puberulous.

Flowers seen rather young. Hypanthium c. 1 mm high, sparsely puberulous. Calyx lobes oblong, 2.5-3 by 0.75-1 mm, glabrous except slightly ciliate on the margins. Petals all similar, oblong, c. 2.3 by 0.3 mm, glabrous. Stamens : filaments 0.6-1.5 mm; anthers c. 1 mm long. Ovary sessile, c. 1 mm long, glabrous, 2-ovuled; style c. 1.5 mm, glabrous.

Pods not stipitate; seed-bearing part suborbicular or broadly ellipsoid, 1.4-1.6 by 1.2-1.4 cm, glabrous, obscurely reticulate; wing 4.5-5.5 by c. 1.5 cm, the basal part gradually narrowed along one lateral side of the seed-bearing part towards its base.

Seeds c. 9 by 8 mm.

Distribution Malesia : Borneo (Sarawak, Kalimantan).

Habitat & Ecology
In lowland forest, up to 80 m altitude
Fl. November; fr. October, November

1. The flowers of the present species are rather similar to those of Genus Caesalpinia .
2. The present species is closely allied to Pterolobium densiflorum ; with the limited collections of these two species examined, it is not easy to distinguish them especially with fruiting material.