Distribution of Aporrectodea and Dendrobaena species (Clitellata: Megadrili) in Iran

Earthworms are considered to be among the largest biological resources in the terrestrial ecosystems and play important roles in ecosystems. Despite their biological, economic, and ecological importance, comprehensive information about their geographical distribution is not available in Iran. The distribution of the two dominant genera, Aporrectodea and Dendrobaena, was investigated in different habitats in Iran. Up to now, five species of Aporrectodea and seven species of Dendrobaena are reported from Iran, namely A. caliginosa (Savigny, 1826); A. jassyensis (Michaelsen, 1891); A. longa (Ude, 1885); A. rosea (Savigny, 1826); A. trapezoides (Dugès, 1828); D. byblica (Rosa, 1893); D. hortensis (Michaelsen, 1890); D. octaedra (Savigny, 1826); D. orientalis Cernosvitov, 1940; D. pentheri Rosa, 1905; D. semitica (Rosa, 1893); and D. veneta (Rosa, 1886). Based on relationship between habitat and richness of different species of these genera, the best habitat for distribution of the genera is the forest habitat. The forest habitat has more species richness than other habitats, due to higher levels of organic matter and moisture.