Dark-barred Twin-spot Carpet Geometridae

Xanthorhoe ferrugata (Clerck, 1759)

Description: Wingspan 24-27mm. Adults are usually pale grey with a dark central band across the forewings. This black banded form ab. unidentaria is much more widespread and predominates over the scarcer red-banded form, which is occasionally seen at light.

Similar Species: This species bears a close resemblance to the Red Twin-spot Carpet X. spadicearia but lacks the pale line at the edge of the central band; the inner band is notched at the costa. All of the Twin-spot Carpets should be examined closely to confirm identification.

Key Identification Features:

Sets:  male upperside

Flight Period: From the beginning of April to early September.

Status: Widespread and commonly encountered in southern counties. Much scarcer further north, where records are mainly from coastal sites. Recorded from Rathlin Island, Antrim in the late 1980s. This species occurs in similar habitats to the Red Twin-spot Carpet X. spadicearia which may account for some misidentifications.

Ecology: Found in a variety of habitats including bogs, fens, and some suburban gardens. Adults come to light frequently and in moderate numbers. The larvae have been reared in captivity on dock Rumex spp and bedstraws Galium spp. It overwinters as a pupa.

Bradley & Fletcher number: 1725 Agassiz number: 70.052

Additional information:

UK Moths account


 Thompson, R. S. & Nelson, B., 2003 (Oct 2). [In] The Butterflies and Moths of Northern Ireland