Xyris formosana Hayata

This species may be no more than a slightly smaller, insular form of Xyris pauciflora which it closely resembles.

Herbs tufted. Leaf sheath keeled; leaf blade narrowly linear, laterally flattened, striate when dry, margin minutely papillose, apex acuminate. Peduncle terete to subterete. Spikes subglobose; basal bracts elliptic, papillose along apical 1/2 of midvein, apex emarginate; median bracts broadly elliptic, papillose on apical, deltoid part, veins 5--7, descendent, midvein dark brown, thick, margin membranous, apex spinulose. Lateral sepals curved, 4--6 × 1.4--2 mm, membranous, hyaline, keeled, base unequally tapering, apical margin usually serrulate, apex subacute to acute; median sepal hooded, ca. 2.5 mm, very thin, hy-aline, 1-veined, apex obtuse. Petal limb obovate, 3-veined. Stamens ca. 0.4 × 0.1 mm; inner anther locule longer than outer one; connective with membranous wing, apex obtuse. Staminodes 2-brachiate, ca. 4 mm. Ovary obovoid, 3-sided, ca. 2.5 mm in diam.

N Taiwan.

* Emersed in marshes; near sea level to 100 m.

Xyris formosana là một loài thực vật hạt kín trong họ Hoàng đầu. Loài này được Hayata miêu tả khoa học đầu tiên năm 1915.

桃园草（学名：Xyris formosana），又名黄葱、台湾黄眼草，为葱草科葱草属下的一个种。