Pirate bug

Orius insidiosus

Orius insidiosus is a small predatory ‘true’ bug. The adults are 2.S—3 mm long, with a dark brown/black head and thorax and distinctively patterned black and white forewings. The eggs are Iaid in plant tissues (without damaging the plant) and there are five nymphal stages, all of which are predatory. First instar nymphs are approximately 0.5 mm long and pale yellow in colour; subsequent nymphal stages become progressively darker, with the final two stages being tan to dark brown_ As in other species of Orius, the nymphs have red

This species is a generalist predator with a preference for thrips (particularly western flower thrips). Young nymphs of O. insidiosus will feed on immature thrips, while adults will attack both adults and immatures. This species will also feed on pollen and on various other pests (including spider mites, moth eggs/small larvae and aphids).

The life cycle (egg to adult) can be completed in 13 days at 28°C (82°F) and in
approximately 20 days at 24°C(75°F). Development and activity is considerably slower
at 20°C (68°F). It is important to note that under short-day conditions and cooler
temperatures, this species will enter ‘reproductive diapause’, during which egg-laying is
suspended_ The onset and termination of diapause are influenced by both temperature
and day length: for example, at 18°C (64°F), the critical day-length is approximately 10-11 hours, while at 20°C (68°F), the critical day-length lies between 12 and 13 hours. Diapause can be avoided by increasing the temperature and/or by using supplemental lighting to increase day-length.