Green lacewings are insects in the large family 'Chrysopidae' of the order 'Neuroptera'. They are often simply called lacewings. Since most of the diversity of 'Neuroptera' are properly referred to as some sort of lacewing, common lacewings is preferable.

Green lacewings are delicate insects with a wingspan of 6 to over 65 mm, though the largest forms are tropical. They are characterized by a wide costal field in their wing venation, which includes the cross-veins. The bodies are usually bright green to greenish-brown, and the compound eyes are conspicuously golden in many species. The wings are usually translucent with a slight iridescence; some have green wing veins or a cloudy brownish wing pattern.

While depending on species and environmental conditions, some green lacewings will eat only about 150 prey items in their entire life, in other cases 100 aphids will be eaten in a single week. Thus, in several countries, millions of such voracious 'Chrysopidae' are reared for sale as biological control agents of insect and mite pests in agriculture and gardens. They are distributed as eggs, since as they are highly aggressive and cannibalistic in confined quarters; the eggs hatch in the field.

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