Arthropods associated with world passalid beetles with particular reference to the Diarthrophallidae (Acari: Mesostigmata)

The data on host–arthropod associations between arthropods and Passalidae are summarised. In the family Diarthrophallidae, the new genus Hamptonilla is established to replace the junior homonym Lombardiniella Womersley, 1961. A total of 404 arthropod species (including those collected from unidentified Passalidae) have been found on 170 species of Passalidae (including those determined as aff.). On Passalidae, arthropods have been found belonging to Astigmata (79 species), Diptera (1), Ixodida (1), Mesostigmata (242), Oribatida (27), Pseudoscorpiones (25) and Trombidiformes (29). Among Mesostigmata, the most species were found in Diarthrophallidae (63), Diplogyniidae (37), Klinckowstroemiidae (36), Fedrizziidae (33) and Megisthanidae (15), among Astigmata in Canestriniidae (68) and among Trombidiformes in Heterocheylidae (26). The largest number of arthropod species were collected from Odontotaenius zodiacus (36), O. striatopunctatus (23), Passalus punctiger (22), O. disjunctus (20), Mastachilus australasicus (17), P. interstitialis (17), Pharochilus dilatatus (14), P. interruptus (13) and Aceraius grandis (11). Arthropods are recorded from 170 species of Passalidae. The least host-specific species are: Tridenchthonius mexicanus (found on 25 species of passalids), Lustrochernes aff. reimoseri (21), Americhernes aff. incertus (12) and L. intermedius (12). The relationships between arthropods and Passalidae are best known in Central America (114 arthropod species from 58 species of Passalidae). In Asia (102 from 32), Oceania (77 from 31), South America (64 from 38), Africa (38 from 13) and North America (20 from 2). Among countries the best studied are Mexico, Brazil, Australia, Indonesia, Philippines, Papua New Guinea and Costa Rica.