Cave-dwelling terrestrial isopods from southern China (Crustacea, Isopoda, Oniscidea), with descriptions of four new species

Seven species of terrestrial isopods from 11 caves in Guizhou, Guangxi and Guangdong provinces (southern China) are recorded. Three species of Armadillidae (Troglodillo latellai, Dryadillo guizhouensis and D. parviocellatus) and one of Exalloniscus (E. troglophilus) are described as new and illustrated. A further new species of Exalloniscus (E. japonicus) is established for specimens previously identified as E. cortii Arcangeli, 1927 from Japan. Two species, Troglodillo latellai and Dryadillo parviocellatus, show some troglomorphic traits, such as the reduction of pigment and number of ommatidia, and can be considered as eutroglophilic forms. Exalloniscus troglophilus belongs to a genus whose species are mainly associated with ants or termites. All the other species are trogloxenous forms.