松叶蕨科 song ye jue ke
Zhang Libing (张丽兵 Zhang Li-Bing); George Yatskievych
Plants small to medium-sized, epiphytic or on rocks. Rhizomes creeping, brown, with protostele or siphonostele, bearing rhizoids; roots absent. Stems erect or pendulous, green, unbranched or dichotomously or pinnately branched; branches ridged to sulcate or complanate. Leaves small or rudimentary, with a single vein (microphylls) or lacking veins (enations), spirally or distichously alternate, sessile or subsessile, dimorphic; trophophylls scalelike and subulate-triangular, or lanceolate to narrowly ovate; sporophylls deeply bifid. Sporangia appearing solitary at or above bases of sporophylls, large, 2- or 3-lobed (sometimes interpreted as synangia of 2 or 3 unlobed sporangia), thickly walled, lacking an annulus, each lobe dehiscing longitudinally by a slit. Spores reniform, monolete, many (> 1000) per sporangium, exospore translucent, rugulate to foveolate. Gametophytes subterranean (Psilotum), non-photosynthetic, cylindrical, mycorrhizal. x = 52.
Two genera (Psilotum, Tmesipteris); one species in China.
Zhang Libing. 2004. Psilotaceae. In: Zhang Xianchun, ed., Fl. Reipubl. Popularis Sin. 6(3): 244–245.
松叶蕨属 song ye jue shu
Plants small to medium-sized, often epiphytic. Rhizomes long creeping, mostly dichotomously branched. Stems erect to somewhat pendulous, glabrous, repeatedly dichotomously branched; branches green, ridged or complanate. Leaves reduced, veinless, sessile, dimorphic; trophophylls scalelike, subulate-triangular; sporophylls deeply bifid. Sporangia 3-lobed, attached at bases of sporophylls. Spores oblong in polar view, reniform in equatorial view, monolete, foveolate.
Two species: widespread in tropical and warm-temperate regions; one species in China.
Psilotum complanatum O. Swartz, which differs from P. nudum in its flattened stems 1.5–3 mm wide, has been reported from Malaysia and Oceania (among other regions). It eventually may be discovered growing in S China.
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 1–2 mm, subulate-triangular, 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; 100–1000 m. Chongqing, Fujian, Guangdong, Guangxi, Guizhou, Jiangsu, Shaanxi, Sichuan, Taiwan, Yunnan, Zhejiang [widespread in tropics and subtropics of Old and New Worlds].