New record of a phoretic flea associated with earwigs (Dermaptera, Arixeniidae) and a redescription of the bat flea Lagaropsylla signata (Siphonaptera, Ischnopsyllidae)

Lagaropsylla signata (Wahlgren, 1903), previously known only from the Island of Java, Indonesia is redescribed and reported for the first time in Deer Cave, Gunung Mulu National Park, Sarawak, Malaysia (west coast of Borneo). Many were found clinging to the earwig Arixenia esau Jordan, 1909. A similar account of a phoretic flea (Lagaropsylla turba Smit, 1958) on the same species of cave-dwelling earwig has been reported in peninsular Malaysia in a well-documented association with the hairless naked bulldog bat, Cheiromeles torquatus Horsfield, 1824. The association of L. signata with A. esau is parallel to the evolution and co-existence with bats in Deer Cave just as in the case of L. turba, A. esau, and C. torquatus. The evidence suggests that L. turba and L. signata are obligate phoretic parasites whose survival depends on A. esau to access a bat host. Arixenia esau is reported for the first time in Deer Cave and the occurrence of L. signata on the island of Borneo represented a new record, previously being found only on the island of Java. Images of L. signata attached to A. esau are provided. Xeniaria jacobsoni (Burr, 1912), often associated with A. esau in other geographical areas, was not present in the material examined from Deer Cave. The natural history of the earwig genera Arixenia Jordan, 1909 and Xeniaria Maa, 1974 are discussed and summarized relative to their associations with phoretic fleas and their bat hosts.