Xyris calocephala Miquel; X. capito Hance; X. paludosa R. Brown; X. robusta Martius.

Herbs perennial, robust. Leaf sheath 7--20(--25) cm; leaf blade ensiform-linear, 15--60 cm × 4--8 mm, glabrous, veins indistinct when dry, connected by numerous, prominent, transverse ribs, apex acute to obtuse. Peduncle 15--65 cm, veins prominent. Spikes ovoid, oblong-ovoid, or ellipsoid, 1.2--3.5 × 1--1.5 cm; bracts yellowish brown, suborbicular, obovate, or conchiform, 5--8 × 5--7 mm, minutely papillose on apical 1/3, base obtuse to truncate, margin gold-colored, membranous, apex entire or emarginate. Lateral sepals linear-spatulate, 5--7 × 0.8--1.4 mm, keel denticulate, apex obtuse; median sepal hooded, 4--6 × 2--2.5 mm, 1-veined. Petals yellowish to yellow; limb obovate to suborbicular, 3--4.5 × 3--4 mm, margin serrulate; claw 3.5--5 × ca. 0.5 mm. Stamens ca. 4 mm; anthers ovate, apex broadly incised, with a short mucro in incision. Staminodes 2--3 mm. Ovary obovoid, 1-loculed. Capsule globose to obovoid, 3--4 mm. Seeds ovoid, ca. 0.5 mm. Fl. Sep--Nov, fr. Oct--Dec.

This species probably occurs in other provinces in S China.

Wet grasslands, inundated rice fields, mountain valleys. Fujian, Guangdong, Hainan [Cambodia, India, Indonesia, Laos, Malaysia, Philippines, Sri Lanka, Thailand, Vietnam; Australia].