Authors: Stefano Taiti, Claudia Rossano (Partner 1)
Terrestrial isopods in different biotopes in the Maremma Regional Park were sampled . This survey complemented previous research by Stefano Taiti in this locality. Species distribution was analysed with relation to the main ecosystems: sandy shores, rocky shores, marsh areas, sclerophyll woods, pine woods, cultivated areas and caves.
At Oued Laou (Morocco) the watershed area was explored from the sources to the river mouth. Species distribution was analysed with relation to the main ecosystems: sandy shores, rocky shores, grasslands, sclerophyll woods, cultivated areas and caves. The two sites were compared and the results show the following.
In both the Italian and Moroccan study sites a large number of terrestrial isopods is present (57 and 37 species, respectively) and several new species have been found (3 and 7, respectively). A zoogeographic analysis of the Oniscidea from the Maremma Regional Park shows that 20 species have limited distributions of Alpine-Apennine and Tyrrhenian origin, with four endemic forms. The terrestrial isopods from the Oued Laou basin are characterized by the presence of some species distributed along the Rif area and the southern part of the Iberian Peninsula. Eight species are apparently endemic to the Rif, but this may be due to the poor knowledge of the Oniscidean fauna of Morocco. The paleogeographic events of the western Mediterranean from the Oligocene (30 Myr) can explain the presence in the Maremma Regional Park of Tyrrhenian forms, systematically close to those present in Corsica and Sardinia, and in the Oued Laou basin of forms with a Rif–Betic distribution. As it could be expected, only a limited number of species (13) are in common between the two study sites, mainly represented by species with a cosmopolitan distribution or littoral species widespread along the coasts of the Mediterranean.