紫萁 zi qi

Osmunda biformis (Bentham) Makino; O. japonica var. sublancea (Christ) Nakai; O. nipponica Makino; O. regalis Linnaeus var. biformis Bentham; O. regalis subsp. japonica (Thunberg) Á. Löve & D. Löve; O. regalis var. japonica (Thunberg) Milde; O. regalis var. sublancea Christ; Osmundastrum japonicum (Thunberg) C. Presl.

Rhizome erect, ascending, or shortly creeping. Fronds 2-pinnate, dimorphic, or rarely hemidimorphic, up to 150 × 50 cm; fiddleheads enveloped by pale reddish brown, long lax hairs, but glabrescent and naked in mature fronds; stipe green or straw-colored, terete, glabrous or glandular hairy when very young; sterile fronds oblong-subdeltoid, 30-50 × 25-40 cm, 2-pinnate; lowest pinnae largest, 20-30 cm; pinnules spreading, oblong-lanceolate to lanceolate, 5-10 × 1-2.5 cm, papery, base truncate to subtruncate, asymmetrical, sessile, margin minutely dentate, apex acute; veins all free, lateral veins joining main veins at ca. 50° angle; fertile fronds 2-pinnate; pinnules linear, 2-4 mm wide, covered throughout with sporangia except on costae, falling soon after spore dispersal. 2n = 44.

Forests, by streams, exposed hillsides, grasslands; 100-3000 m. Anhui, Chongqing, Fujian, Gansu, Guangdong, Guangxi, Guizhou, Henan, Hubei, Hunan, Jiangsu, Jiangxi, Shaanxi, Shandong, Sichuan, Taiwan, Xizang, Yunnan, Zhejiang [Bhutan, N India, Japan (including Ryukyu Islands), Kashmir, Korea, Myanmar, Pakistan, Russia (Sakhalin), Thailand, Vietnam].