any member of the insect family Chrysididae (Chrysalidae) of the order Hymenoptera. The family is large, common, and widely distributed. More than 1,000 species of the genus Chrysis alone have been described. Most cuckoo wasps are small, seldom exceeding 1.2 cm (about 0.5 inch) in length. The colour is usually metallic green or blue. The flexible abdomen allows the insect to curl into a ball when disturbed or attacked.
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