House dust mites in three contrasting climatic regions of Saudi Arabia

Just a handful of mite species are suspected inhabiting the dust of houses within arid areas of the Arabian Peninsula. In this study, we identified and compared the house dust mite diversity in three different climatic areas within Saudi Arabia. Sampling was carried out over one year and two months, with samples collected in the desert, the coast, and in the highlands. It reviews all known mites of house dust of Saudi Arabia. A total of 998 mites were collected belonging to 23 species in 14 families. Pyroglyphidae (Astigmata) were the most abundant. The interaction among pyroglyphid species in the climatic regions was analysed. While variation in abundance of Pyroglyphidae among regions was weak, there was a strong desert region Cheyletus eruditus-Dermatophagoides farinae association, perhaps explaining that D. farinae populations from the desert have become C. eruditus' favourite prey. Another interesting association is that of Pyroglyphidae with Acaridae. D. pteronyssinus shows significant numerical dominance in the highlands. A newly discovered species of Dermatophagoides did not interact with any of the other 2 species and was restricted to the coastal region. Dermatophagoides n. sp. and Cheletopsis sp. can be used as markers of location in forensic analyses (provenance), based on their unique association with the coast and desert, respectively. A new species of Dermatophagoides has been identified. Five species are new to Saudi Arabia and the Arabian Peninsula including house dust, ten species are new to the house dust mite fauna of Saudi Arabia and the Arabian Peninsula but have been recorded as storage mites, totalling 15 new house dust mites for the Arabian Peninsula. Two species are new to house dust in Saudi Arabia, but already known from house dust in Kuwait. Of the fifteen new house dust mites for the Arabian Peninsula, five species are new to the dust mite fauna worldwide: Prostigmata: Cheletopsis sp. (Cheyletidae); Mesostigmata: Proctolaelaps pygmaeus (Melicharidae), Macrocheles muscaedomesticae (Macrochelidae); and Oribatida: Oribatula tibialis (Oribatulidae), and Ceratozetes sp. (Ceratozetidae).