1. Psilotum nudum (Linnaeus) P. Beauvois, Prodr. Aethéogam. 112. 1805.
松叶蕨 song ye jue
Lycopodium nudum Linnaeus, Sp. Pl. 2: 1100. 1753.
Rhizomes creeping, terete, brown, with dense rhizoids. Aerial stems erect to somewhat pendulous, green, with dense white stomata, 15-50 cm, 0.8-1.5 mm wide, glabrous, unbranched proximally, distally repeatedly dichotomously branched, 3-angled or -ridged. Trophophylls subulate-triangular, 1-2 mm, herbaceous; sporophylls deeply bifid, lobes narrowly subulate, 2-3 mm. Sporangia yellow to yellowish brown, obtriangular-globose, 3-4 mm in diam., (2 or)3-lobed. 2n = 104, 208, ca. 312.
Epiphytic on trees or rock crevices; near sea level to 1000 m. Anhui, Chongqing, Fujian, Guangdong, Guangxi, Guizhou, Hainan, Hunan, Jiangsu, Jiangxi, Shaanxi, Sichuan, Taiwan, Yunnan, Zhejiang [widespread in tropics and subtropics of Old and New Worlds, extending northward to Korea and Japan].