Seasonal occurrence and habitat distribution of tenebrionid beetles on a coastal sand dune (Circeo National Park, Italy)

The tenebrionid community inhabiting a Mediterranean dune ecosystem (Circeo National Park , central Italy) was analysed to study ( 1 ) the distribution and diversity of these beetles in three different plant assoc i ations , and (2) the seasonal changes of the community composition and structure . Monthly samplings were made by sieving a fi xed volume of sand and detritus . Most species showed a different abundance in the three habitat s , and substantial differences were observed i n the monthly values of species richness and diversity. A decrease of the overall density was observed from the external to the innermost plant associ ation , characterized by a higher plant cover. The community also showed clear temporal phases, with an overall decrease in w inter and summer, confirming a pattern previously observed also in other soil arthropods living in Mediterranean arid environments