Description from Flora of China
Calophyllum smilesianum Craib; C. smilesianum var. luteum Craib; C. thorelii Pierre; C. williamsianum Craib.
Trees ca. 25 m tall. Young shoots gray puberulous, indistinctly tetragonous, old ones terete. Petiole 1-2 cm, adaxially broadly sulcate; leaf blade abaxially usually glaucous, oblong-elliptic or ovate-elliptic, rarely lanceolate, 5.5-9.5 × 2.5-4.3 cm, leathery, midvein raised on both surfaces, base cuneate and decurrent, margin somewhat revolute, apex acuminate but with an obtuse tip. Thyrse terminal, rarely axillary, always shorter than leaf blade; peduncle short or also nearly absent. Pedicel 4-10 mm, densely rusty-puberulous. Flowers white. Sepals ciliolate on margin, apex rounded; outer 2: oblong-ovate or broadly elliptic, rarely obovate, ca. 2.5 mm; inner 2: equal, elliptic-obovate, ca. 4.5 mm. Petals absent. Ovary ovoid, ca. 1.7 mm; stigma peltate. Infructescence usually with 1 or 2 fruit. Fruit globose, 2-2.5 cm, apiculate. Fl. Apr-May, fr. Sep-Oct. 2n = 22.
Dense forests in valleys; 1100-1800 m. S Yunnan (Jinghong, Lancang) [Bangladesh, Bhutan, N India, Laos, Myanmar, Thailand, Vietnam].