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.

Ecosystems comprising coastal lakes and ponds are important areas for preserving biodiversity. The natural reserve “Saline di Trapani e Paceco” is a

Invasive alien species (IAS) are one of the greatest causes of native species extinction. Indeed, they represent a global threat for biodiversity and can also affect the economy and human health. The colonization success of IAS is presumably not only due to their biological and ecological characteristics, but also to the lack of predators and/or parasites in the invaded new areas. In the present work, we demonstrate evidence of predation of the invasive alien crab Percnon gibbesi (H. Milne Edwards, 1853) by the Rock Goby Gobius paganellus Linnaeus, 1758. The diet of G. paganellus was studied analyzing the stomach content of 162 specimens collected in the central Mediterranean Sea. The results obtained from the calculation of the diet indices, namely, frequency of occurrence (%F), percentage weight (%W), percentage abundance (%N), and the Index of Relative Importance (%IRI), showed that small benthic crustaceans were the main prey types. Additionally, these indices and the Levins’ index (Bi) clearly indicated that the invasive crab P. gibbesi was by far the most abundant prey type in the diet of G. paganellus. The relevance of this predator–prey interaction and the role of native species for the biological control of invasive ones are discussed. We also provide a general view on the diet of G. paganellus and other biological and ecological aspects of specimens studied from the central Mediterranean Sea.

Specimens of Porcellio variabilis coming from Tunisian populations were genetically and morphologically examined. Ten loci were analysed by Multilocus Enzyme Electrophoresis (Mdh ₁, Mdh ₂, Idh ₁, Idh ₂, Got ₁, Got ₂, Pgm, Est ₁, Acph, Phi). The low values of genetic distance (average D_N = 0.101) and the morphological differences found between the various populations do not allow a clear separation, even if the population of Ain Drahem shows the most significant differentiation with respect to all the others (about 0.150 for D_N values).