Dark-barred Twin-spot Carpet - Xanthorhoe ferrugata

Wingspan 18 to 22 mm. The character to separate this species from Red Twin-spot Carpet was previously thought to be a notch on the inner edge of the median fascia close to the costa, but this is no longer considered completely reliable although it is still likely to remain true for the majority of individuals. Any individual showing a very dark, almost black, median fascia with no hint of red or purple tones is likely to be Dark-barred Twin-spot Carpet, whereas any individual with reddish tones is very likely to be Red Twin-spot Carpet. The underside of the forewing differs between the two species and can be checked in fresh individuals, being uniform grey with little contrast in Dark-barred Twin-spot Carpet and showing a contrasting pattern with deep ginger colouration towards the apex in Red Twin-spot Carpet. Both species come in differing forms, however a reddish form of Dark-barred Twin-spot Carpet does seem to be much scarcer than a darker form of Red Twin-spot Carpet, and is unlikely to be prevalent in any population. 

Red Twin-spot Carpet

To help clarify the status and range of Dark-barred Twin-spot Carpet in VC55, ensure that any candidates are photographed showing both upper and underside of the forewing. Individuals that are worn should either be dissected or ignored.

Various habitats.

The moths fly in May and June, and again in August. Further north there is usually only one brood, in June and July.

The larval diet consists of a variety of low plants.

Fairly common throughout Britain. In a recent survey to determine the status of all macro moths in Britain this species was classified as common.

Likely to have been previously over-recorded in Leicestershire and Rutland, present status unclear however it is certainly less common than Red Twin-spot Carpet.