Dyscia fagaria, the grey scalloped bar, is a moth of the family Geometridae. The species was first described by Carl Peter Thunberg in 1784 and it can be found in Europe. The wingspan is 31–40 mm (1.2–1.6 inches), the females are a bit smaller. The colour of the wings varies from whitish to brown. The outer cross line on the front wings consists of dark points (often connected) and is well developed. The interior cross line is similar to the outer, but only weakly implied in some specimens. The discal stain stands out clearly. The dark outer cross line of the forewings continues in attenuated form on the hindwings. There are fine black dots on the margins of all wings. Ab. alvarensis Wahlgren is rather a light form and weakly marked, the lines only distinct at the margins; ab.favillacearia