Vertical distribution of Hormogaster elisae (Oligochaeta, Hormogastridae) in soil at El Molar (Central Spain)

The vertical distribution of Hormogaster elisae in soil between November 19 92 and October 1994 was studied at El Molar (Central Spain). This species s hows a marked seasonal variation in vertical distribution, inhabiting the t opsoil through the humid months and migrating into lower depths through the dryer periods. H. elisae lives at a mean depth of 17.88 cm and its seasona l variations in depth are correlated with soil moisture. The numbers of ind ividuals in vertical layers is correlated significantly with soil moisture but not with rainfall. Significant correlations among vertical distribution of mature, semimature and immature worms did not occur.