Preliminary Studies of the Pteridophytes of Yunshan Nature Reserve in Hunan Province

Yunshan Nature Reserve is situated in Southwest Hunan and extends from 110°22′～111°03′E, 26°25′～27°00′N with an area of 83 km 2. After a floristic analysis of the pteridophytes of Yunshan, some five general conclusions are obtained, which are shown in the following. (1) According to the investigation and collected data, up to now, 34 families, 67 genera and 137 species are recorded in Yunshan, of which the largest families and genera are Selaginellaceae, Polypodiaceae, Thelypteridaceae, Athyriaceae, Dryopteridaceae, Pteridaceae and Selaginella, Pteris, Athyrium, Dryopteris, respectively. (2) Genera are rare in the families, 1 genus in 25 families; 2～4 genera in 5 families; and 5 or more genera in 4 families. Species are also rare in the genera, 1 species in 38 genera; 2 species in 13 genera; 3 species in 5 genera; 4 species in 5 genera; and 5 or more species in 6 genera. (3) The types of pteridophytic area pattern are rich in number; the types of genera and species area pattern are divided into 13 types and 12 types respectively. This pteridophytic flora has the temperate character of East Asia. In the floristic composition of this area the families of tropics and mainly tropics distribution make up 67.65% of the total families; the genera of tropics distribution make up 59.71% of the total, but the species of temperate distribution make up 72.99% of the total. (4) In Yunshan, there is 1 Chinese endemic genus and 30 Chinese endemic species including 2 endemic species are found. (5) This pteridophytic flora is a transitional one from the tropical to the temperate. It belongs to the area of Central China, Holarctic Kingdom.