The wingspan is 25–35 mm.. The forewings show a variety of ground colors ranging from pale yellow through orange yellow, reddish yellow to brown yellow, and purple brown. The midfield is always obscured and is bordered by lines, which reveal a significant bend and in addition show a nearly identical, parallel course. There are one or two more crosslines in the midfield, which also have a nearly parallel course, but are however much less developed. In the midfield also the cell stands out, the midfield bulges out and there is dark crossline. The marginal field is often brightened whitish brightened and a wavy line is missing. Below the apex, there is a large, prominent, crescent-shaped spot. The fringes are plain brown. The hindwings shimmer white, the edge is grayish and has an indistinct gray crossline.The larva is a rather pale yellowish brown, often with some tinge of green; weakly marked, the most conspicuous
marking being a dark dorsal line.[1]
Figs.2, 2a larvae after final moult
Adults are on wing from July to mid-September. There are two generations per year in the Netherlands and only one in the UK and North America.
^Prout, L. B. (1912–16). Geometridae. In A. Seitz (ed.) The Macrolepidoptera of the World. The Palaearctic Geometridae, 4. 479 pp. Alfred Kernen, Stuttgart.pdf * This article incorporates text from this source, which is in the public domain.