The hemisarcoptid mite Hemisarcoptes coccophagus Meyer was reared on armored scale insects (Homoptera: Diaspididae) whose shields were replaced by artificial, transparent covers. Mite development (egg to egg) lasted 26-28 days at 21°C, 15-16 days at 28°C. Unmated females produced no eggs, fertilized ones laid an average of 16/female, and the male: female ratio was 1: 2. Female hosts which were attacked by less than 10 mites deposited few or no eggs, while scales parasitized by more mites died. H. coccophagus attacked the latania scale, Hemiberlesia lataniae (Signoret), on acacia trees in the autumn as soon as the scale population recovered from summer desiccation. Up to 61 0J0 of the scales were parasitized. Aphytis diaspidis (Howard), a hymenopterous parasite, replaced H. coccophagus in attacking most of the scale population during early spring. It is concluded that Hemisarcoptes might be suitable for the biological control of pest scales which are not being concomitantly attacked by other natural enemies.