Dicopomorpha echmepterygis is the smallest known insect and a species of parasitic wasp in the family Mymaridae, which exhibits strong sexual dimorphism. The males are blind, apterous, and their body length is only 40% that of females.

With a body length averaging 186 μm (for 8 specimens measured, which ranged from 139 to 240 μm), males of D. echmepterygis have the shortest body length of all known insects (smaller than certain species of Paramecium and amoeba, which are single-celled organisms). The measured body length of a female was 550 μm. The eggs and larvae of this parasitoid are considerably smaller than the adult.

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