The subfamily Rhyparochrominae has been regarded as principally predaceous. Adults and nymphs of Geocoris punctipes Say are common predators on European red mite, Paratetranychus pilosus C. & F., on cotton in the southern United States (McGregor & McDonough 1917). The nymphs consume ca. 1,600 red spiders during their development, and adults account for ca. 80 per day. Eggs are laid singly among the hosts, and the life cycle from egg to adult is ca. 30 days. In Fiji, Germalus pacificus Banks is regarded as an important natural enemy of the fruit fly, Chaetodacus passiflorae Frogg. Nymphs and adults suck the contents of the eggs, which are embedded in the fruit rind (Clausen 1940/1962).
There are about 22 genera, and include the insects that are known as chinch bugs, milkweed bugs, and also some seed bugs. Most species feed on seeds, although some are predators of other insects. There are also sap feeders (mucivory), and others that are hematophagous (blood-sucking).
Lygaeidae is a large cosmopolitan family with more than 2,050 species described species as of 1993. Diagnostic characters include a forewing membrane with only 4-5 simple veins, 4-segmented antennae and rostrum, 3-segmented tarsi, there are pulvilli present, and the ocelli are ususally present. Most are dull colored and of 3-15 mm. in size.
Most species are phytophagous, but some in the subfamily Geocorinae, the "big-eyed bugs," are facultative predators with a wide host range that includes phytophagous insect. There are Myrmecophilous, coprophagous, and saprophagous, but the seed-feeding species outnumber other types. They are not used in biological pest control directly, but some Geocoris spp. are considered important to the agroecosystem.
Grimaldi, D. A. & Michael S. Engel (2007). "An unusual, primitive Piesmatidae (Insecta: Heteroptera) in Cretaceous amber from Myanmar (Burma)" (PDF). American Museum Novitates 3611: 1–17
Miller, N. C. E. 1971. The Biology of the Heteroptera. E. W. Classey Ltd., Hampton Middlesex, England. 206 p.
van Duzee, E. P. 1917. Catalogue of the Hemiptera of America North of Mexico, Excepting the Aphididae, Coccidae and Aleurodidae. Univ. Calif. Publ., Tech. Bull. Ent. II. 902 p.