Abstract
The diversity of Oniscidean isopods was studied in Vendicari, a protected area in southeastern Sicily characterized by salty ponds separated from the sea by narrow bands of land. Samples were collected in pitfall traps placed in transects from the coastline to the ponds and from the ponds inland. Twenty-three species were identified, only seven of which were present at all sampling sites. Shannon's diversity and Pielou's evenness indices revealed higher values in the spring and autumn; activity indices were also calculated for each species for all months of the year. Similarity among sampling sites was evaluated qualitatively with Jaccard's index and quantitatively with Sørensen's index. The ponds seem to play the same role as the seacoasts regarding species zonation.
Acknowledgements
The authors would like to thank the “Corpo Forestale di Siracusa” for permission to work in the study area. In addition they are very grateful to Dr. Saverio Sciandrello for his help in identifying plant association.