Four new records of mites (Acari: Astigmata) phoretic on insects in Riyadh, Saudi Arabia

A survey was carried out to investigate astigmatid mites associated with four unrelated insect species, belonging to four families. The four insect species, Musca domestica (Linnaeus, 1785) (Diptera: Muscidae), Labidura riparia (Pallas, 1773) (Dermaptera: Labiduridae), Gryllus bimaculatus (DeGeer, 1773) (Orthoptera: Gryllidae), and Periplaneta americana (Linnaeus, 1758) (Blattaria: Blattidae), collected from different localities in Riyadh, were observed. Four astigmatid mites (Caloglyphus csibbii Eraky, Histiostoma camphori Eraky, Histiostoma pickaxei Eraky and Shoker, and Myianoetus lili Eraky) belonging to two families, Acaridae and Histiostomatidae, were recorded on G. bimaculatus, L. riparia, P. americana, and M. domestica, respectively. All recorded mites are considered new to Saudi Arabian mite fauna. One individual of Copronomoia sphaerocerae (Vitzthum) (Histiostomatidae) mite, previously recorded in Saudi Arabia, was found on M. domestica. For each mite species found, notes on density and attachment sites are given. An identification key, based on deutonymphal stages, for the five mite species reported in this study and other phoretic astigmatid mites previously recorded on insects in Saudi Arabia is provided.