Peristylus formosanus (Schlechter) T. P. Lin, Native Orchids Taiwan. 2: 274. 1977.台湾阔蕊兰 tai wan kuo rui lan
Habenaria formosana Schlechter, Repert. Spec. Nov. Regni Veg. Beih. 4: 127. 1919, based on H. tentaculata (Lindley) H. G. Reichenbach var. acutifolia Hayata, J. Coll. Sci. Imp. Univ. Tokyo 30(1): 354. 1911; H. brevicalcarata Fukuyama (1932), not (Hayata) Masamune (1968); Peristylus flagellifer(Makino) Ohwi var. acutifolius (Hayata) Hatusima; P. lacertifer (Lindley) J. J. Smith var. formosanus(Schlechter) S. S. Ying, nom. superfl.
Plants slender, 15-45 cm tall. Tubers subglobose, 1-2 × 0.8-1.5 cm. Stem with 2 or 3 tubular sheaths at base, 3- or 4-leaved. Leaves forming a basal rosette to somewhat spaced along stem, elliptic to ovate-lanceolate, 5-10 × 2-3 cm, apex obtuse or acute. Inflorescence 13-36 cm; peduncle cylindric, slender; sterile bracts 2 or 3, lanceolate, to 1.5 cm; rachis 6-20 cm, densely many flowered; floral bracts ovate-lanceolate, 8-12 mm, basal ones exceeding flowers, apex acuminate. Flowers erect to horizontal, whitish green; ovary 8-10 mm including pedicel. Dorsal sepal erect, ovate, concave, 3.5-4 × 2.2-2.5 mm, apex obtuse-rounded; lateral sepals spreading, oblong-elliptic, 3.8-4.8 × ca. 1.8 mm, apex subobtuse to acute. Petals connivent with dorsal sepal and forming a hood, ovate-rhombic, 3.8-4.8 × ca. 2.5 mm, apex acute; lip narrowly ovate, ca. 4 × 1.8 mm, deeply 3-lobed near base; disk with a large, subglobose callus near base; lateral lobes diverging widely from axis of lip, filiform, 5-12 mm; mid-lobe ligulate, 1.7-3 mm, apex obtuse; spur saccate-ovoid, neck contracted, ca. 2 mm, apex subacute. Column ca. 1.5 mm; viscidia oblong; rostellum with short arms. Fl. Aug-Dec.
Open places, grasslands; below 300 m. Taiwan [Japan (Ryukyu Islands)].
"Caeloglossum formosanum" [sic] (Makino & Hayata, J. Coll. Sci. Imp. Univ. Tokyo 22: 420. 1906) belongs here but is a nomen nudum and was therefore not validly published.
The identity and placement of this species within the genus remains contentiou