Description & Statistics
Barber (1936) gave an early account of the behavior of Orius (= Triphleps) insidiosus Say in North America. In corn this species was a predator of Thysanoptera, Homoptera and to some extent Hemiptera, Lepidoptera and Acarina. It was considered the most important natural enemy of the corn earworm, Heliothis obsoleta F., in certain areas of the United States. Records from Virginia showed that the proportion of eggs destroyed ranged from 14-54% during the season. Young larvae were also attacked, though to a lesser extent (Clausen 1940/1962).
Pirate bugs average about 1.5 mm to 5 mm long. Their body is oval to triangular and somewhat flattened, sometimes with a black and white patterned back.
Pirate bugs feed on other small insects, spider mites and insect eggs. They cut a hole into their prey, pump saliva into it and drink the contents. This makes them beneficial as biological control agents. Orius insidiosus, the "insidious flower bug", for example, feeds on the eggs of the corn earworm (Helicoverpa zea). Especially O. insidiosus is often released in greenhouses against mites and thrips.
These small insects can bite humans, with surprising pain for such a small insect. However, they do not feed on human blood or inject venom or saliva. In some people the bite swells up, in others there is no reaction
Orius insidiosus was also the most effective natural enemy of a number of species of thrips attacking truck crops and fruit trees, and this was also true in relation to the European red mite and other mites on various crops. McGregor & McDonnough (1917) performing feeding experiments, found that a nymph consumed an average of ca. 33 mites daily and adults a slightly lesser number. Mite eggs were attacked only when the young and adults became scarce. Extensive feeding was noted on the winter eggs of the European red mite during late summer. Several species of Acanthocoris were found to feed on aphids in Britain; A. nemoralis F. had the unusual habit of attacking leaf mining larvae of the lepidopteran genus Lithocolletis (Butler 1923).
This cosmopolitan family had around 302 known species as of 2011. Diagnostic characters of these "minute pirate bugs" of "flower bugs" include a forewing usually with a well-defined embolium, a clavus, and a membrane with few or no veins and no closed cells. The rostrum and tarsi have 3 segments; ocelli are present; and antennae have 4 segments. Most species are black with white markings and are small (2-5 mm.).
Most Anthocoridae are predaceous, a few species are phytophagous, and one species is known to be a facultative, though regular, bloodsucker of humans, horses and cattle. Most anthocorids feed on small insects and insect eggs, mostly Thysanoptera and Homoptera, and sometimes on Hemiptera, Lepidoptera, Acarina, and Coleoptera. The more common species live around flowers, but some also occur under loose bark, in leaf litter, and in decaying fungi and animal wastes. Some species apparently are cosmopolitan on account of their being transported via stored products such as rice and copra, among which they find coleopterous larvae and other insect pests and mites. One species was introduced from the Philippines via Hawaii into California for biological control of the Cuban laurel thrips.
China, W. E. &* N. C. E. Miller. 1959. Checklist and keys to the families and subfamilies of the Hemiptera-Heteroptera. Bull. Brit. Mus. Nat. Hist. Ent. 8(1): 1-45.
Miller, N. C. E. 1971. The Biology of the Heteroptera. E. W. Classey Ltd., Hampton Middlesex, England. 206 p.
Southwood, T. R. E. & D. Leston. 1959. Land and Water Bugs of the British Isles. London Publ. 436 p.