形態特徵

• Rhizome horizontal, 5-7 cm long, about I cm thick; stipes without aerophores, nearly triangular in c. s. at base, the upper part of stipe nearly terete.
• Sterile fronds 40-50 cm tall, pinnate; lamina 15 to 20 cm long, stipes 12 to 25 cm long; lower 3 to 5 pairs of pinnae petiolate, medial pinnae sessile, the upper pinnae adnate; frond ending in a terminal pinna, similar to lateral ones, about 3 cm long, adnate at base to uppermost lateral pinna; lateral pinnae 6 to 10 cm long, 1-1.5 cm broad.
• Fertile fronds usually shorter than sterile, being 15 to 35 cm long, pinnate; lower 5 to 6 pairs of pinnae petiolate, the upper pairs often sessile, terminal pinna often longer than upper lateral ones.
• <i>Plagiogyria koidzumii</i> differs from all of our other <i>Plagiogyria</i> in having a horizontal rhizome.

分布

• 世界 : the Ryukyus.

引證標本

NANTOU: Chingshuikou, Huang 943; Chitou, Huang 1488.

參考文獻

• SHIEH, WANG-CHUENG, DEVOL, CHARLES E. and LU, CHIN-YI, Flora of Taiwan, second edition 1: 137. 1994.  (Fl. Taiwan 2nd edit.)