Some families of Suborder Actineadida play a considerable role in biological control i.e. (Cheyletidae, Cunaxidae, Stigmaeidae, and Tyeidae). Majority members are great importance to agriculture small insects, scale insects and their eggs and immature stages of some soil insects and nematodes.

This study was under taken to study the biological aspects on the common predacious Cunaxid mite species, Coleoscirus buartus. It was reared on free living nematode (Rhabditella muscicola Chitwood) at 26 ^o C±20C and 70-75
R.H. Current Studies showed that: 1-Incubation period for females was slightly higher than males averaged (6.1±0.2) and (5.7±0.2) days, respectively. 2- Life cycle for female and male was averaged (19.2±0.4) and
(13.9±0.4) days, respectively. 3-The larval, protonymphal and tritonymphal stages of the female required an average of (2±0.1), (2.01±0.1), (1.7±0.2) and (3±0.1) days, respectively. 4- while the larval, protonymphal and deutonymphal stages of male required an average of (1.9±0.1), (1.91±0.2) and (1.6±0.2) days, respectively, shorter than female. 5-The total period required for longevity of female and male was (28.2±1) and (16±0.6) days, respectively. 6- The immature of female was (13.1±0.4) days, while the immature of male was (8.3±0.3) days.

Male reached adult stage earlier than female. 7- Number of deposited eggs per female averaged (40.9±1.7) egg, daily mean 1.8 egg/day. 8- Feeding capacity to Coleorscirus buartus Consumed free living nematode Rhabditella muscicola Chitwood1 predator female immature greater number of prey than male immature. The total averaged (53.5±1.5) and
(31.2±1.4) preys for female and male, this resulted from the absence fed on greater number of preys (318.l ±7.6) individuals (12.8/day), than male (219±11.6) individuals (10.04/day). 9- Adult stage proved to be most effective predacious stage as fed on greater number of preys amounting more than six times of the consumed by immature. 10- Sex ratio 1:4 male/female when reared in the laboratory. 11- While the predator C. buratus Passes through egg, one larval and three nymphal stage before reaching adult hood female where as the male passed through egg, larva and two nymphal stages before becoming an adult do not observed tritonymph of male.