Ocneria detrita is a species of moth of the Lymantriidae family. It is found in France, Italy and parts of central, south-east and eastern Europe. The wingspan is 30–34 mm. Adult males have a brownish-grey ground colour with dark markings. Females are similar in colour, but lack any markings. Adults are on wing from the beginning of June to the end of September in one generation per year. The larvae feed on Quercus species. They have a dark, almost black, body and head. The species overwinters in the larval stage.