Studies on the interrelation between rodents and their ectoparasitic acarines in Riyadh region, Saudi Arabia.

The ectoparasitic acarines of commensal and wild rodents collected from various areas in Riyadh Region were four species of mites (Laelaps nutalli, Ornythonyssus bacoti, Cheyletus eruditus and Articholaelaps glasgowi), and two species of ticks. (Immature stages) Rhipicephalus spp. and Hyalomma spp. In urban areas the highest infestation rate by mites was 49.9% on Rattus rattus followed by 18.5% on Rattus norvegicus. The highest rat-mite index was 2.3 on R. rattus followed by 1.3 on R. norvegicus and 0.1 on Mus musculus. In semiarid areas, the highest rat-mite index was 2.1 on Gerbillus spp. followed by 1.7 on Meriones spp., 1.6 on Jaculus jaculus and 0.9 on Acomys dimidiatus. The highest infestation rate by mites was on Meriones spp. followed by Gerbillus spp. and then A. dimidiatus.