Idaea subsericeata

Idaea subsericeata, the satin wave, is a small pale moth of the family Geometridae. It was first described by Adrian Hardy Haworth in 1809 and ranges from central and southern Europe and North Africa through Asia Minor to Transcaspia. The wingspan is 22 to 25 millimetres. The ground colour is white with a strong silky gloss, crossed by greyish lines, usually five on the forewing and four on the hindwing, though the outermost line is often missing. Apart from size, the species is not very variable, and second-brood adults tend to be smaller and whiter beneath. The egg is oval, first light yellow and later bright orange with red spots. The slender caterpillar is whitish grey to brown with a slightly reddish back, and the pupa is blackish brown to golden brown. Larvae feed on low growing plants such as knotgrass, dandelion and chickweed. Adults fly in one generation from June to July in the British Isles, favouring warm slopes, sunny forest edges and clearings, hedgerows, dry grass, fallow fields, abandoned vineyards and dry coastal salt marshes.