Species abundance and zoogeographic affinities of Chinese terrestrial earthworms

Terrestrial earthworm variously reported from China number amounts to 298 species with 84 of these, or 28%, non-natives for which 67% are Asiatic Megascolecidae and 22.6% are Lumbricidae of Holarctic origin. All the 298 species belong to 8 families and 27 genera. Among of them, 59 species are new species or new records after 1992. Using SPSS 12.0 to establish the distributional relationships among genera and species, we could draw a conclusion that the numbers and abundances of species in the South of China were more abundant and richer than that in the North of China. Megascolecidae was dominant in China, amounting to 243 species. The numbers of wide-range species and wide-range genera were 11 and 6, respectively, and about 3.7% of total species and 22.2% of total genera. Most species only are distributed in one or two Provinces, which indicates most genera and species have a bias to limitation of distribution. That Lumbricidae distributes in Oriental region still could not define its origin. It is not clear that the origin of earthworms among the seven Provinces, but the species abundance in Oriental region is much richer than that in Palaearctic region. Molecular (DNA and RNA) methods may solve the problems of identification and origin.