On the systematic position of Athyrium crenulato-serrulatum Makino from North-eastern Asia

Ching Ren-Chang, Wang Zhong-Ren

Received:1900-01-01 Revised:1900-01-01 Online:1982-02-18 Published:1982-02-18
Contact: Ching Ren-Chang

Abstract:

The fern Athyrium crenulato-serrulatum Makino is found in the whole of

Northeastern Asia embracing Northeastern China, Korea, Japan, Ussuri and the Far

East USSR. It is similar to the European Athyrium distentifolium, formerly known

as A. alpestre, in having exindusiate round or ovate sori, but differs in several

essential characters, such as the well-spaced fronds are biseriately arranged along a

thick and long-creeping rhizome, the base of stipe is thickened and not attenuated to-

wards the point of attachment, the deltoid-ovate lamina with the basal pinnae as long

as those next above, which all are distinctly petiolate and the rachis, costis and espe-

cially the costules of pinnules clad in fine pale-colored generally septate hairs under-

neath. All these clearly show that the fern in question is not an Athyrium sen. str.

neither Pseudoathyrium Newman to which latter the fern was referred by Nakai.

However, we have been long suspicious of its proper systematic position. In his recent

monograph on the genus Cornopteris (Acta Phytotax. Geobot. 30: 104. 1979.) Kato

has pointed out that C.crenulato-serrulata (Makino) Nakai “has the northernmost

destribution in the genus and exhibits a few characteristics similar to Athyrium, the

swollen base of stipes with projections and cartilaginous lamina margin. By these

characteristics the species is clearly discriminated from other species”. According to

Kurita (1964), Mitui (1970) and Karo (1978) the species in question has chromosome

numbers n=40, the base number of the subfamily Athyrioides instead of x=41, the

base number of the subfamily Diplazioides including Cornopteris Nakai. Since the

fern in question fits no other athyrid genera, hence a new genus is proposed.

Ching Ren-Chang, Wang Zhong-Ren. On the systematic position of Athyrium crenulato-serrulatum Makino from North-eastern Asia[J]. .

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