肾蕨 shen jue

Polypodium cordifolium Linnaeus, Sp. Pl. 2: 1089. 1753, nom. cons.; Aspidium cordifolium (Linnaeus) Swartz; A. tuberosum Bory ex Willdenow; Dryopteris auriculata (Linnaeus) Kuntze; Nephrodium tuberosum (Bory ex Willdenow) Desvaux; Nephrolepis auriculata (Linnaeus) Trimen, nom. utique rej.; N. tuberosa (Bory ex Willdenow) C. Presl; P. auriculatum Linnaeus, nom. utique rej.

Plants terrestrial or epiphytic. Rhizome erect, short, covered with yellowish brown, narrowly lanceolate scales; stolons bearing scaly tubers (1-1.5 cm in diam.). Stipe 5-15 cm, densely covered with same scales as on rhizome; lamina linear-lanceolate or narrowly lanceolate, 25-75 × 3-6 cm, pinnate; pinnae 40-120 pairs, approximate, lanceolate, 1.5-2.5 × 0.6-1.2 cm, unequal at base, margin serrulate to crenate, auricle acute, lower pinnae obtuse, gradually shorter upward; rachis with sparse, fibrillar scales. Sori lunulate or rarely orbicular-reniform; indusia brown, elongate.

Forests, along streams; near sea level to 1500 m. Fujian, Guangdong, Guangxi, Guizhou, Hainan, Hunan, Taiwan, Xizang, Yunnan, Zhejiang [Bangladesh, Bhutan, Cambodia, India, Indonesia, Japan, Korea, Laos, Malaysia, Myanmar, Nepal, Pakistan, Philippines, Singapore, Sri Lanka, Thailand, Vietnam; Africa, SW Asia, Australia, North and South America, Pacific islands].

Slender plants of Nephrolepis cordifolia are sometimes mistaken for N. undulata (Afzelius) J. Smith (Bot. Mag. 72: 35. 1846; Aspidium undulatum Afzelius, J. Bot. (Schrader) 1800(2): 32. 1801; Nephrodium delicatulum Decaisne; Nephrolepis delicatula (Decaisne) Pichi Sermolli; N. occidentalis Kunze; N. paucifrondosa J. F. R. Almeida), but this species has not (?yet) been found in China. Nephrolepis undulata can be recognized by its slender, seasonal rhizome, which usually does not bear more than one or two fronds at the same time, whereas N. cordifolia forms perennial rhizomes that regularly bear five or more well-developed fronds.

We do not follow the identification by Jarvis (Order Out of Chaos, 759. 2007) of Polypodium auriculatum Linnaeus (Sp. Pl. 2: 1088. 1753) with Nephrolepis biserrata.