New records of exotic species of Oniscidea (Crustacea: Isopoda) from northern Mexico

To date 86 species of 33 genera and 16 families of Oniscidea have been recorded in Mexico. Collections of 4 academic institutions and recent field materials were revised. From 1,820 specimens, 1,417 (77.6%) were determined to belong to 6 exotic forms. A taxonomic account and a species identification key with SEM plates of these exotic entities are presented. For morphological analysis we used light and SEM microscopy. The molecular identity of 5 of the 6 forms was examined through cytochrome oxidase 1 gene (mtDNA) analyses. The exotic species determined are: Armadillidae, Cubans murina, Armadillidiidae, Armadillidium vulgare, Porcellionidae, Agabiformius lentus, Porcellio laevis, P. scaber, and Porcellionides pruinosus. The exotic oniscideans were recorded from urban, rural and natural (riparian) zones in 15 states of northern Mexico, including the first formal records in Aguascalientes, Chihuahua, Durango, and Zacatecas. Atmadillidium vulgare, P. laevis, and P. pruinosus often co-occurred and are the most widely distributed species in this region. Although most of the material examined was recorded from urban zones (> 50% of studied sites), A. vulgare and P. laevis were also found in riparian areas (natural zones), yet P. pruinosus was recorded mainly from riparian areas (60% of 45 lots examined).