The Oak Lutestring (Cymatophorima diluta) is a species of moth in the Thyatiridae family.This species is local in Britain, inhabiting mature oak woodlands. This species well distributed in southern England, and north to west Wales and Cumbria where the habitat is suitable. Flying from late Summer till Autumn, this species pupates in Spring and early Summer, and can be found on wine ropes, light and sugar. There are two strong cross bands on this species, which are green-brown, while the base colour is grey. Overwinters as egg.