Geometridae, Larentiinae - Wingspan: 30-38mm.

A common species throughout the UK, and widespread in Cornwall. Males (example shown here) have an area in the posterior part of the fore-wing which is reddish tinted, making up the common name for this species. Females are without this, generally just having an overall greenish tint when fresh. Both may lose this tint as they get older, but they can be identified by the prominent whitish spot near the fore-wing tip, and the rest position brings the narrower fore-wings closer together.

The flight season is almost the reverse of most other "Carpets", as, although a single generation, adults fly from late September up to the end of the year. Hibernation can occur through the winter months, December to March, before again becoming active from April to June. Depending upon the weather conditions, individuals may be seen active at times all through these periods.