The four species of Whitfordiodendron share several characters with the new genus Kanburia but bracteoles are present on the calyx and persistent in Whitfordiodendron (vs. absent in Kanburia). The keel petals are densely sericeous in Whitfordiodendron (vs. glabrous in Kanburia and Callerya). The pods in Whitfordiodendron are inflated and ovoid with a velutinous or pubescent surface (vs. linear, compressed, glabrescent in Kanburia). The ovoid seeds in Whitfordiodendron may become fused together when there are more than one per pod (vs. lenticular, separate in pod in Kanburia). The wing petals are equal in length with the keel petals in Whitfordiodendron (vs. shorter in Callerya).

Whitfordiodendronscandens Elmer.

Scrambling climbers 10–20 (– 40) m tall. Stems grey or brown, terete, glabrous or finely grey puberulent. Leaves with 3–13 leaflets, evergreen, nitid above, glabrous or sparsely pubescent, imparipinnate, rachis 9–25 cm long. Stipules 1–4 mm long, narrowly deltoid, caducous (persistent W.erianthum). Stipels absent. Leaflets large, 4–15 (– 25) x 2–9 (– 12) cm, ovate, narrowly elliptic or obovate, apex acuminate to cuspidate, margins entire, base rounded or obtuse or acute. Inflorescence a terminal panicle 5–20 cm long, peduncle sericeous (cauliflorous and glabrescent 20–60 cm long in W.nieuwenhuisii). Flowers 8–23 mm long, emerging from February – November (May to January W.nieuwenhuisii). Floral bracts 2–7 mm long, ovate, obovate or elliptic, caducous. Bracteoles at base of or on the calyx 2–7 mm long, obovate, acute or acuminate, persistent. Pedicels 0.5–2 mm long, pubescent or sericeous. Calyx 2–9 × 3–5 mm campanulate, oblique, ferrugineous, golden or silvery pubescent or sericeous externally, five lobed, teeth unequal (0.5 –) 2–4 mm long, acuminate, pubescent on teeth. Standard 8–18 × 9–16 mm, suborbicular or elliptic, inner surface greyish pink, white flushed purple, red, maroon or claret, nectar guide yellow or green, back of standard densely red or golden-brown sericeous, apex acute or obtuse. Callosities ridge or boss type. Wing petals 8–18 × 2–5 mm, sparsely pubescent or ciliate along lower margin (sericeous at apex in W.erianthum), equal in length to the keel, broadly obovate, free from the keel, apex obtuse, basal claws 2–4 mm long. Keel petals 8–10 × 3–5 mm, sericeous externally especially along lower margin, obovate, claw 2–4 mm long, apex obtuse. Stamens diadelphous, nine fused together, the vexillary one free, all curved upwards at apex. Ovary sericeous, style 2–4 mm long, ciliate, curved upwards at apex, stigma punctate. Pods 4–10 × 2–5 cm, inflated, ovate or obovate, with two thickened margins either side of suture on both sides of pod, dehiscent, surface rugose or ruminate or sparsely pubescent or pale brown velutinous, subseptate. Seeds 1–3, broadly ellipsoid or ovoid, 12–45 × 14–35 × 8–30 mm (often fused together when more than one), hilum central, broadly elliptic 3–5 × 1–2 mm.

Brunei; Indonesia (Sumatra, Borneo: west Kalimantan); Malaysia (Peninsula, Borneo: Sabah, Sarawak); Philippines.

Whitfordiodendron for Whitford and dendron = tree (Gk). The genus commemorates Harry Nichols Whitford (1872–1941) world authority on the economics of rubber and on the native forests of the Philippines.