Author: (de Wit) Cusset
Morphological description (see also description of Genus Bauhinia ; Subgenus Phanera and Section Phanera)
(sylvani Bauh Reinw f11 )
Giant liana with up to 60 m tall stems. Young branches brown woolly, strongly angulate and longitudinally grooved; tendrils densely brownish hairy.
Leaves: stipules foliaceous, auriculate-orbicular, densely hairy outside, thinly pubescent inside, up to 2.5 cm diameter; petiole stout, brown, woolly, up to 7 cm long; lamina ovate rotundate, 8-20 cm diameter; 15-17-nerved; bifid c. 1/4-1/3 with more or less broad sinus; tip of lobes rounded; base very deeply cordate; upper surface almost glabrous except for the very base where the petiole is inserted; lower surface woolly-tomentose; connecting nerves strongly marked, perpendicular to the main nerves.
Inflorescence stout, terminal racemes, densely brown tomentose with axis up to 25 cm long, 5-7 mm thick, angular, c. l0-flowered; pedicels tomentose, 4-5 mm thick, 1.5-6 cm long, gradually merging into the 7-10 cm long hypanthium; bracts ovate, 10-15 mm long, caducous; bracteoles lanceolate, c. 10 mm, inserted at the base of the hypanthium.
Flowers: Buds ellipsoid-clavate, velvety brown, 2.5-4 by 1-1.5 cm. Calyx splitting into 5 reflexed, strap-shaped lobes, hairy on both sides. Petals creamy yellow, obovate, somewhat differing in size, the upper smaller than the lateral, 5-6 by 2-2.5 cm, densely velvety outside, sparsely hairy inside; claw 1-2 cm long. Stamens 3 fertile, yellowish-green; filaments 6-7 cm long, anthers c. 1 cm long, opening by a longitudinal slit; staminodes 2, c. 1 cm long. Ovary reddish-brownish hairy, stipe c. 1 cm, angulate, ovary c. 2 cm; style recurved, c. 1 cm, hairy except for the very apical part; stigma large, peltate, 3-4 mm diameter
Pods dehiscent, strap-shaped, 30-40 by 6-7 cm, densely rusty tomentose.
Seeds c. 10, flat, elliptic-ovate to orbicular, 2.5-3 cm diameter.
Distribution
Malesia: endemic to Borneo where it has been collected in a few places in Sarawak (districts Kutei, Temiai and Kakus), and in Sabah (district Tenom).
Habitat
Along riverbanks in primary forests and mixed dipterocarp forests at altitudes between 200 and 450 m.