Eupithecia simpliciata, the plain pug, is a moth of the family Geometridae. It is found in the Palearctic ecozone, from western Europe to north-western China (Xinjiang). The wingspan is 21–23 mm. Eupithecia simpliciata has a relatively broad rounded forewing. The forewing ground colour is pale ochre.The forewing has indistinct, curved fuscous striae.The postmedian fascia has curved pale edges, the outer one zig-zagged towards the tornus.The forewing fringes are chequered.The hindwings are whitish-grey, darkened in the postmedian field. The discal spot is small. The butterflies vary significantly in colour and pattern. T