These strange-looking insects, known to feed on human household objects, can range up to 4.3 cm (1.7 in) in length. A 350 million year old form was known to grow quite large, at up to 6 cm (2.4 in). Thrips (Thysanoptera) Members of the genus Phasmothrips are the largest kinds of thrips. The maximum size these species attain is approximately 1.3