Species diversity and conservation of endemic land snail fauna of Palau islands

根据我们自己实地调查收集的标本和一些已发表的文献，我们在帕劳群岛发现了166种陆地蜗牛。166种中，引进种5种，广布种或邻近地区特有种7种，特有种149种。流行率很高(89。7%)，约60%的特有种为未描述种。一些特有物种表现出广泛的形态多样性和生态分化，表明在这些群体中发生了适应性辐射。值得注意的是，帕劳岛特有的陆地蜗牛动物群仍然存活着150多种，而在太平洋其他岛屿地区，大多数特有的陆地蜗牛已经灭绝或濒临灭绝。

Based on specimens collected by our own field surveys and some published literature, we recognized 166 species of land snails to be occurred in Palau islands. Among the 166 species, 5 species was introduced, 7 were widely distributed species or indigenous species common to neighboring region, and 149 were endemic species. Endemic rate was very high(89. 7%) and approximately 60% of the endemic species were undescribed species. Some of the endemic species show extensive morphological diversity and ecological differentiation, suggesting that adaptive radiation have occurred in those groups. It is remarkable that endemic land snail fauna comprised of more than 150 species is still surviving in Palau island, while most of endemic land snails were already extinct or endangered in other area of Pacific islands.