Orius insidiosus, also called the minute pirate bug, is an aggressive thrips predator, possibly the most effective. It attacks and kills all mobile stages of thrips, including adult thrips. Orius is a true bug, which means it has a long rostrum. It uses its rostrum to pierce its prey, and drain the contents, killing the pest. A generalist predator, Orius feeds on many pest species, such as mites, aphids and moth eggs for food. It will control thrips, and helps in the control of the other pest species. Adult Orius eat all thrips stages, while younger Orius nymphs only eat thrips larvae. Orius can also feed on other prey such as aphids, mites or moth eggs. They sometimes kill more insects than strictly necessary for their own feeding. Orius also eat pollen, allowing preventive introductions in pollen bearing crops such as sweet pepper, gerbera, strawberry and eggplant. Life-style The adult female is 3mm long and lays two to three eggs per day in plant tissue. Eggs are tiny 0.4mm, and difficult to see. One nymph hatches per egg. Nymphs pass through five stages before maturing. Total development time egg to adult is about three weeks. Adults live approximately three to four weeks. The first nymphs are colourless, and darken as they mature; going from yellow to brown. Fifth-stage nymphs have wing pads. All nymph stages have red eyes. Adults are black and have a characteristic white patch on its back. Orius females may enter diapause when daylength is less than 12 hours. Releases of Orius are possible during this time, but one should not expect establishment. Orius is aggressive, it consumes 12 thrips per day but kills many more 45 than it eats.
Life Cycle and Biology
Orius insidiosus has multiple generations per year. The total developmental time from egg to adult is approximately three weeks. Adult females lay their eggs within plant tissues. Eggs hatch in six to ten days. Orius insidiosus undergoes incomplete metamorphosis, and nymphs develop through five instars. Development of the nymph requires at least ten days, depending on temperature. Adults live for approximately three to four weeks. Nymphs and adults are highly mobile. When day length is less than 14 hours, adults will enter a quiescent resting state.
Hosts
Orius insidiosus is found in a wide range of agricultural crops and natural habitats. It is attracted to flowers and plants that have soft-bodied insects feeding on them. Pollen and plant juices are known to be used as food when prey is scarce. Nymphs and adults feed on a variety of small prey, including thrips, mites, aphids, whiteflies, scale insects, small caterpillars, and eggs of various insects.