Mimosa caesia Linnaeus, Sp. Pl. 1: 522. 1753; Acacia caesia var. subnuda (Craib) I. C. Nielsen; A. intsia (Linnaeus) Willdenow var. caesia (Linnaeus) Wight & Arnott ex Baker; A. intsia var. oxyphylla Graham ex Baker; A. oxyphylla Graham var. subnuda Craib.

Climbers, with recurved prickles on internodes. Branchlets and leaf rachis tomentose or glabrous. Stipules filiform, ca. 3 × 1 mm; petiole with gland 0.3-1 cm above base, in lower half of petiole, and glands on rachis between several upper pinnae; pinnae 6-8(-13) pairs, 3.5-9.5 cm; leaflets 8-19 pairs, oblong, (0.6-)1-1.2 cm × (1.1-)4-5 mm, both surfaces glabrous, main vein starting from center of leaf base, close and parallel to upper margin, apex apiculate. Heads less than 1.2 cm in diam., 1-4 arranged in panicles; peduncles tomentose. Flowers yellow. Calyx 1.5-2 mm; lobes ovate, 0.3-0.5 mm, apex acute. Corolla 2-3 mm; lobes ovate-elliptic, (0.5-)1 mm. Ovary 0.8-1 mm, puberulent to velutinous; stipe ca. 1.5 mm. Legume strap-shaped, 10-15 × 2-3 cm, dehiscent, sutures straight or slightly sinuous, base attenuate, stalklike. Seeds 8-12. Fl. Sep, fr. Nov.

Secondary forests; 200-2500 m. Guangdong, Hainan, Sichuan, Taiwan, Yunnan [Bangladesh, Cambodia, India, Laos, Myanmar, Sri Lanka, Thailand, Vietnam].