The Polynesian rat Rattus exulans is the third most common species of Rattus, after the cosmopolitan brown rat R. norvegicus and black rat R. rattus. However, despite its wide distribution and great natural and economic importance, its acarofauna is poorly known. It has been found to host a species of demodecid mite that is new to science, Demodex exulantis sp. nov. which occurred in various areas of the hairy skin of the body. Demodecidae occupying analogous locations and with similar morphological features are typical skin parasites in other Muridae of Eurasian origin, including host species of the genera Apodemus, Mus and Bandicota. However, no such mite has previously been identified in hosts of the genus Rattus. The present study confirms the universality of this pattern of skin colonization of this group of rodents, i.e. with the dominant mite species associated with the hairy skin of the entire body. The identified model of skin infestation by co-occurring/synhospital demodecid mites, with the dominant species inhabiting hair follicles, may be a universal pattern for Demodecidae colonizing all mammalian groups. The present discovery also constitutes the first record of Prostigmata skin mites in R. exulans, and we present a global checklist with an updated list of Demodecidae records in murids.http://www.zoobank.org/urn:lsid:zoobank.org:act:2CF24B22-4566-453C-9D42-F755DAA5778Bhttps://zoobank.org/NomenclaturalActs/2cf24b22-4566-453c-9d42-f755daa5778b
Rolbiecki et al. (Tue,) studied this question.