Introduction Co-phylogenetic studies of parasitic mites and their hosts have been conducted on several lineages of acariform mites of mammals and birds in recent years (OConnor 1987; Klompen 1992, 1993; Mironov and Dabert 1999; Ramery et al. 2000; Bochkov 2001; Bochkov and Fain 2001; Dabert et al. 2001; Ehrnsberger et al. 2001; Dabert 2003). The acariform mite family Atopomelidae is the most species-rich lineage of per- manent parasites living attached to the fur of small mammals, i.e. marsupials, ‘insectivores’, primates and rodents (OConnor 1982). Because most of their supraspecific taxa are associated with particular host groups (Fain 1994), mites of this family are good potential models for co-phylogenetic studies; however, only two studies have utilised modern approachs to phylogeny reconstruction of particular atopomelid groups (Bochkov and Fain 2003; Bochkov et al. 2004 [2005]). Atopomelid mites are widely distributed, being known from both northern and southern hemispheres, but are largely limited to tropical or subtropical climates. To date, 47 genera and more than 370 species of atopomelid mites have been described, and five centres of their biodiversity have been recognised: mainland Africa, Madagascar, South-east Asia, Australia–Oceania and the Neotropical region (Fain 1972a, 1972b, 1976a, 1979, 1981). Among atopomelid mites, the subgenus Listrophoroides (sensu stricto) Hirst, 1923 is the most species-rich and phylo- genetically problematic group. Its 39 species are associated primarily with Asian rodents in the family Muridae, sub- family Murinae, with three species found on African murines (Fain 1972a, 1981; Fain and Bochkov 2003; Bochkov and Mironov 2001; Bochkov et al. 2004). The known host associ- ations of Listrophoroides (sensu stricto) species have not been critically analysed. Many species were described from only one or a few specimens, rendering some published host associations questionable. With a better understanding of host associations and geographic ranges, these mites may provide useful data for co-phylogenetic and biogeographic studies. In particular, such research may help elucidate the relative importance of the processes of vicariance and dispersal of their murine hosts from Indochina to islands of the Sunda Shelf and beyond. In addition, mites of this lineage present a fascinating example of ‘synhospitality’ (Eichler 1966), with 36 species parasitising species of the murine genus Maxomys Sody, 1936. Twenty-three of these species occur on Maxomys surifer (Miller, 1900), where several mite species may co- occur on the same host individual (Fain 1981). This work represents the first attempt to reconstruct phylogeny of Listrophoroides (sensu stricto) using a parsi- Invertebrate Systematics, 2005, 19, 437–498 10.1071/IS05017 1445-5226/05/050437 © CSIRO 2005 Andre V. Bochkov A,B,C and Barry M. OConnor A A Museum of Zoology, University of Michigan, 1109 Geddes Ave, Ann Arbor, MI 48109, USA. B Zoological Institute of the Russian Academy of Sciences, Universitetskaya embankment 1, 199034 St Petersburg, Russia. C Corresponding author. Email: bochkov@umich.edu Abstract. Phylogenetic relationships among species of the parasitic mite subgenus Listrophoroides Hirst (Atopomelidae), fur-mites of Asian and African murine rodents, are reconstructed on the basis of parsimony analysis of morphological characters. This group is polyphyletic with respect to the outgroup, subgenera Marquesania Womersley and Paklistrophoroides Fain & Hyland. The mite phylogeny partially reflects the host phylogeny and several groups of closely related species associated with particular rodent groups are recognised. The rajah-group, with 34 species associated with rats of the genus Maxomys Sody, is most diverse. Most Maxomys species are parasitised by a single mite species but some of them harbour a complex of several species. Maxomys surifer (Miller), the most widespread species of the genus, hosts unique species combinations comprising 23 species in different parts of its range. This synhospitality is hypothesised to have originated during Pleistocene isolation of different host populations in multiple rain forest refugia. The current species complexes also reflect later host range expansions. These data are consistent with a hypothesis of Pliocene vicariance in some Sunda Shelf rodents and not with the traditional view of widespread migration across the Late Pleistocene Sunda Shelf. The rajah species-group is revised, 16 species are described as new and three are synonymised. Phylogeny and host associations of the fur-mite subgenus Listrophoroides (sensu stricto) Hirst (Acari : Atopomelidae) with an intriguing example of synhospitality on rats of the genus Maxomys www.publish.csiro.au/journals/is CSIRO PUBLISHING