1. Osmundastrum cinnamomeum (Linnaeus) C. Presl, Gefässbündel Farrn. 18. 1847.
桂皮紫萁 gui pi zi qi
Osmunda cinnamomea Linnaeus, Sp. Pl. 2: 1066. 1753; O. asiatica (Fernald) Ohwi; O. cinnamomea subsp. asiatica (Fernald) Fraser-Jenkins; O. cinnamomea var. asiatica Fernald; O. cinnamomea var. fokienense Copeland; Osmundastrum asiaticum (Fernald) X. C. Zhang; O. cinnamomeum var. asiaticum (Fernald) Kitagawa; O. cinnamomeum var. fokiense (Copeland) Tagawa; Struthiopteris cinnamomea (Linnaeus) Bernhardi.
Rhizome creeping or ascending, short, bearing approximate fronds seemingly in a crown. Fronds dimorphic, young fronds densely covered with long, lax hairs, glabrescent and nearly naked when mature; stipe short, enlarged and winged at base, fleshy when young; sterile fronds pale yellowish green, pinnate-pinnatifid, ovate-lanceolate, 30-80(-100) × 15-25 cm, soft papery, gradually narrowed toward acuminate apex; pinnae sessile, more than 20 pairs, 5-20 × 1.5-3 cm, incised ca. 2/3 toward costa, apex acuminate; ultimate lobes entire, margin with hairs often mixed with black ones, apex rounded; lateral veins forked; fertile fronds usually shorter and developing earlier than sterile fronds, 2-pinnate; pinnae sessile, 2-4 × ca. 1.5 cm, incised almost to costa; ultimate segments 2-4 mm wide, covered throughout with sporangia. 2n = 44.
Often in dense populations in marshy places in mountainous areas; 600-2600 m. Anhui, Chongqing, Fujian, Guangdong, Guangxi, Guizhou, Heilongjiang, Hunan, Jiangxi, Jilin, Sichuan, Taiwan, Yunnan, Zhejiang [N India, Japan, Korea, Russia (Far East, Siberia), Vietnam; North America].
Osmundastrum cinnamomeum and Osmunda claytoniana are very similar in general morphology, except the degree of dimorphism of the fronds. The fronds of O. claytoniana are hemidimorphic (vs. dimorphic), and the sterile pinnae are ca. 3 cm wide or more (vs. ca. 2 cm wide or more).