毛叶蕨 mao ye jue

Trichomanes pallidum Blume, Enum. Pl. Javae 2: 255. 1828; Craspedoneuron pallidum (Blume) Bosch; Crepidomanes pallidum (Blume) K. Iwatsuki; Pleuromanes pallidum (Blume) C. Presl.

Plants 4-12 cm tall. Rhizome light brown, ca. 0.3 mm in diam., with light brown spreading hairs, with sparse rootlets. Stipes 0.5-3 cm apart, dark brown, 1-6 cm, with light brown hairs at base, glabrous upward, wingless. Lamina bipinnatifid to bipinnate, oblong or ovate-lanceolate, 3.5-8 × 1-2 cm, base cuneate, apex obtuse; pinnae 8-10 pairs, closely spaced or slightly imbricate to neighboring ones, alternate, sessile, oblong-ovate to ovate, 1-1.8 cm × 5-6 mm, oblique, base cuneate, margin parted, apex obtuse; ultimate segments closely spaced, linear, 0.8-1 mm wide, with a single veinlet, entire, obtuse at apex. Veins filiform, brown, dichotomous. 2n = 72.

On wet muddy rocks or tree trunks in dense forests; 800-1400 m. Hainan, S and SE Taiwan [India, Malesia, Sri Lanka, Thailand, Vietnam; Australia, Pacific islands (Melanesia, Micronesia, Polynesia)].

A less-hairy form collected in E and SE Taiwan was attributed to Hymenophyllum acutum (C. Presl) Ebihara & K. Iwatsuki (Blumea 51: 232. 2006; Trichomanes acutum C. Presl, Hymenophyllaceae, 42. 1843; Crepidomanes acutum (C. Presl) K. Iwatsuki) by Knapp (Ferns Fern Allies Taiwan, 442. 2011). However, further study is needed.