Hypoaspis solimani n. sp. was collected from compost from the farm of the Faculty of Agriculture, Cairo University, Giza, Egypt. Morphological characters of the different stages are described, illustrated and a key to the Egyptian species of Hypoaspis presented. H. solimani sp. n. was successfully reared on larvae of house fly, Musca domestica L. and vinegar fly, Drosophila melanogaster Morgan, and the two soil fungi, Macrophomina phaseoli and Fusarium oxysporum. The two kinds of prey proved to be the favoured diet, accelerating development and increasing female longevity and fecundity.

The predacious mites Amblyseius gossipi El-Badry and A. swirskii Athias-Henroit developed, survived and reproduced successfully on several artificial diets. The best diet consisted of 1 g yeast, 1 g milk, 30 mg cystine, 30 mg proline, 30 mg arginine, 20 mg sucrose, 50 mg glucose, 30 mg streptomycin sulphate and droplets of sorbic acid. Mean eggs/female/day by the two predators was 0.54 and 0.30 when reared on the best diet compared to 1.21 and 0.40 when fed on a natural diet, respectively. Female longevity of A. swirskii was 84.3 days, nearly twice as long as that on a natural diet Eggs showed no abnormalities; larvae fed on diets had normal development, and adults were comparable in size to individuals reared on a natural diet.

The predacious mite, Cydnodromella negevi (Swirski & Amitai) completed life cycle when fed on the tetranychid mites Eutetranychus orientalis (Klein), Tetranychus urticae Koch and pollen grains of Ricinus communis (L.) as an alternative food substance in the laboratory. The duration of the immature stages and adult stage were determined. Immature stages of C. negevi consumed in total an average of 27 E. orientalis and 34 T. urticae, whereas each day throughout her life, the adult female consumed an average of 11 of E. orientalis and T. urticae. While feeding on these prey, C. negevi laid 1.3 and 1.0 eggs per day. The number of eggs deposited per day increased (3.3 eggs/female/day) when fed on eriophyid mites. Females neither fed nor reproduced on liquid nutrients.

The predacious mite, Pachylaelaps aegyptiacus Hafez & Nasr completed life cycle when fed on eggs of housefly, Musca domestica (L.) at 25 ± 2°C and 70–80% r.h. in the laboratory. The durations of the immature stages and of the adult stage were determined. Immature stages of P. aegyptiacus consumed in total an average of 16 eggs of housefly, whereas each day throughout her life, the adult female consumed an average of 7.6 eggs of housefly. Daily rate of single and multiple mating was 0.93 and 1.0 eggs/female respectively. Description of immature stages of the predatory mite was given.

The predacious mite, Hypoaspis vacua (Michael) successfully developed from larva to adult stage when fed on eggs of housefly, Musca domestica (L.) and nymphs of acarid mite, Rhizoglyphus echinopus (Fum. & Rob.) in the laboratory. The duration of the immature stages and of the adult stage were determined. Food type greatly affected female fecundity and feeding capacity. Immature stages of H. vacua consumed in total an average of 13.6 eggs of M. domestica and 33.0 nymphs of R. echinopus, whereas each day throughout her life, the adult female consumed an average of 4.1 eggs of M. domestica and 13.23 nymphs of R. echinopus. Eggs of housefly were the most suitable diet, as it prolonged adult longevity (76.8 days) and increased female fecundity (1.3 eggs/female/day).