Description: Deciduous tree, to ca 30 m tall; buttressed; bark reddish-brown. Stipules 1–2 cm long, keeled, caducous. Leaves opposite, ovate, 9–20 cm long; apex acute; base cordate; blade sparsely hirsute above, pubescent below; secondary nerves 6–10 on each side; domatia hairy; petioles 5–12 cm long, pubescent. Inflorescences solitary head, axillary, cluster of 2–4(–10), ca 2 cm in diam.; peduncle 4–10 cm long. Flowers many, creamy yellow turning orengish; bracteoles small; calyx campanulate, lobes 5, ca 1.5 mm long; corolla salverform, fine hairy outside; tube 5–6 mm long; lobes 5, 1–2 mm long; filaments short; anthers 1–2 mm long. Ovary ca 2 mm in diam., pubescent; style and stigma exserted for 5–7 mm. Fruiting head 1–1.5 mm in diam; capsules obovoid, 4 valves, 4–5 mm long, pubescent; seeds numerous, winged.

Photos: Phongsak Phonsena (Khon Kaen)