Carsia sororiata

Carsia sororiata, the Manchester treble-bar, is a moth of the family Geometridae. The species was first described by Jacob Hübner in 1813. It is found in northern and central Europe, the Urals, Siberia, the Far East, northern Mongolia and in North America from Alaska to Newfoundland and to New Hampshire.

Illustration from John Curtis's British Entomology Volume 6

Carsia sororiata
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Lepidoptera
Family:	Geometridae
Genus:	Carsia
Species:	C. sororiata
Binomial name
Carsia sororiata (Hübner, 1813)
Synonyms
Geometra sororiata Hubner, 1813 Phalaena paludata Thunberg, 1788 (preocc. Linnaeus, 1767) Geometra imbutata Hubner, 1813 Larissa imbutata (Hübner, 1809-13) Carsia boreata Packard, 1873 Carsia anglica Prout, 1937

The wingspan is 20–30 mm. The basic colour of the forewings is slate grey, light grey to white grey. Two distinctive, wide lines cross the front wing. They are light brown, brown to black brown. The interior cross line is almost straight, the exterior cross line is bent and has two outward pointing spikes. The subspecies occurring in Central Europe, C. s. imbutata, has a brownish-yellowish to reddish-brown outer field at the points of the outer cross line. Very elegant lines are sometimes found. In some specimens, the two lines form "bridge" in the posterior half of the wing. The fringes are alternately bright and dark. An apical extension to the reddish-brown field extends from the apex.[1]

Adults are on wing from July to August.

The larvae feed on various Vaccinium species (including V. uliginosum, V. oxycoccos and V. myrtillus) as well as Rubus arcticus.