莎草蕨 suo cao jue

Acrostichum digitatum Linnaeus, Sp. Pl. 2: 1068. 1753; Actinostachys boninensis Nakai; A. digitata (Linnaeus) Wallich.

Rhizome shortly creeping, bearing several erect fronds; hairs on rhizome and stipes multicellular, brown, ca. 2 mm. Fronds crowded, linear, 20-30 cm tall, with indistinct stipes, simple and entire except for apical soriferous portion, 2-3.5 mm wide, with distinct midrib, recurved when dry, basal 2-5 cm portion resembling stipe, triangular in cross section; apex of vegetative portion of fronds constricted, bearing 5-15 soriferous lobes digitately. Soriferous lobes 2-4 cm × ca. 1 mm, entire; sporangia covering whole abaxial surface of soriferous lobes, without paraphyses.

Forming small populations on rather dry forest floors in lowlands. Guangdong, Hainan, Taiwan, Yunnan [India, S Japan, Myanmar, Thailand, Vietnam; widely distributed in palaeotropics from Madagascar to Polynesia].