Remarks. The family Eustathiidae is restricted to swifts (Apodiformes: Apodidae and Hemiprocnidae). Up to now, this family has included 63 described species in 16 genera (Kwanyuen, 1973; Peterson et al., 1980). In studies conducted so far, three aforementioned eusththiid species, Eustathia cultrifera, Chauliacia securigera, Neochauliacia minuscula, and also Thysanocercus cypseli (Canestrini and Berlese, 1881) (Analgoidea: Thysanocercidae) are known to be common on Apus apus (Kwanyuen, 1973; Peterson et al., 1980; Gaud and Peterson, 1987).