Machilus thunbergii seeds mature in July.红楠 hong nan. Evergreen trees, usually 10-15(-20) m tall; trunk 65-130 cm d.b.h. Bark yellowish brown. Older branchlets rough; young branchlets purple-brown when fresh, glabrous. Buds ovoid or oblong-ovoid; bud scales golden brown or reddish brown, suborbicular, leathery, ciliate, apex rotund, outer scales puberulent, inner ones tomentose outside. Petiole slender, 1-3.5 cm, reddish when fresh; leaf blade lustrous on both surfaces, abaxially glaucescent, obovate to obovate-lanceolate, 4.5-9(-13) × 3-6 cm, leathery, glabrous on both surfaces, midrib distinctly elevated abaxially, somewhat impressed adaxially, lateral veins 7-12 pairs, slightly straightly ascendant, nearly curved at margin, veinlets obscure, base cuneate, apex obtuse or abruptly cuspidate. Inflorescences arising from base of young shoots, 5-11.8 cm, branched at upper part of peduncle, glabrous, many flowered. Pedicel 6-9 mm. Perianth lobes oblong, ca. 5 mm, outer ones narrower, slightly short, apex acute, glabrous outside, pubescent toward apex inside. Filaments glabrous, those of 3rd series with stipitate glands at base. Staminodes hispid at base. Ovary globose, glabrous; style slender; stigma capitate. Fruit green becoming dark purple, compressed globose, 8-10 mm in diam.; peduncle and fruiting pedicel reddish purple. Fl. Feb, fr. Jun-Aug.