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Endemism in the Flora of China—Studies on the Endemic Genera


China,  under highly varied ecological conditions resulted from wide lati-
tudinal and altitudinal ranges and from the adequate precipitation,  has developed a
very rich flora of great diversity. As far as flowering plants are concerned,  there are
2980 genera,  214 of which,  belonging to 64 families,  are endemic.  Among these ende-
mic genera,  there are 9 genera of taxads and conifers, 19  genera of monocots  and
others of dicots.  Of the approximately 129 herbaceous endemic genera in the Chinese
flora as a whole,  about 22 (17%) are annual and 107 (83%) are biennial or perennial.
In the present paper the ecological distribution,  the nature of endemic genera and the
centers of endemism are discussed.
     1.  Three types of endemic genera are distinguished,  neoendemics,  palaeoendemics
and active epibiotics,  The endemic genera in the flora of China are,  for the most part,
considered to be very old ones,  and most of them are of temperate nature.
     2.  the degree of endemism in our 22 floristic regions is shown in Figure 1.  The
areas richest in endemic genera in the Chinese flora as a whole are the 13,  16 and 17
regions.  The poorest are the 2,  4,  9 and 10 regions,  and no one in the 1 and 3 regions
These results on floristic richness are of general applicability.
     As shown in table 1,  the difference in the degree of endemism among the seven
Chinese floristic subkingdoms are most pronounced.   101 endemic genera are known
to occur in one subkingdom,  72 to occur in two subkingdoms,  and 3 to occur in four
subkingdoms,  only one genus widely distributed in five subkingdoms.  However,  there
is no genus occurring in seven subkingdoms. The difference in the degree of endemism
in each subkingdom reveals that the distribution of endemic genera is not well-distri-
buted in the Chinese flora as a whole.
     Analysis of the vertical distribution of the 200 endemic genera of the Chinese
flora bears out that there is no evident increase in endemism as a whole with altitude.
     3.  Three centers of endemism are found (Fig. 2).  These are as follows:
     a).  Eastern Sichuan-western Hubei center.
     b).  Southeastern Yunnan-western Guangxi center.
     c).  Western Sichuan-northwestern Yunnan center.  The degree of endemism and
characters of endemic genera in each center are discussed.


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