(6) 細齒黑桫欏
Gymnosphaera hancockii (Copel.) Ching
桫欏科 (Cyatheaceae)
英文名
(English name): Toothed Black Tree-fern
Status in China: Vulnerable (VU). Wild plant under State protection (category II).
Photo credit: Dr. M. L. So
Description: Medium-sized ferns, 60-100 cm tall. Trunk short, sometimes prostrate, densely covered with scales. Leaves tufted; stipes slender, reddish brown, with scattered warts; lamina lanceolate, bi-to tripinnate; pinnae alternate, short-stipitate, oblong, longest to 30 cm long; pinnules alternate, subsessile, oblong, divided almost to the costa; segments oblong, more or less oblique, apex rounded, margin toothed; one or two basal segments sometimes free; veins pinnate from the costa, simple or rarely forked. Sori rounded, borne on the middle of veins, in one series along each side of the costa, without indusium.
Distribution: Sunset Peak, Tung Chung, Tai Mo Shan. Guangdong, Jiangxi, Fujian, Taiwan; Japan.
Habitat and Ecology: Thick forests of valleys or streamsides.
The species was previously placed in the genus Alsophila. Its systematic position is still controversial and is thus of great botanical interest. In Hong Kong, some localities of its occurrence are protected in Country Parks. This species is also protected by the Forestry Regulations (Cap. 96 sub. leg.) and the Protection of Endangered Species of Animals and Plants Ordinance (Cap. 586).
References:
Edie, H. H., 1977: Ferns of Hong Kong, 87. Hong Kong Univ. Press. Hong Kong.
So, M.L., 1994: Hong Kong Ferns, 44. The Urban Council, Hong Kong.