A vulnerable Red Data Book species, in saltmarshes in parts of south-eastern England, protected under the UK Wildlife and Countryside Act, and a priority species under the UK Biodiversity Action Plan. The sole British site for this species is the Hamford Water estuary in Essex. Unlikely to be recorded in Hampshire or on the Isle of Wight. Wingspan 42-58 mm. The only possible confusion species is the much smaller
Frosted Orange G. flavago in which the forewing is orange instead of ochreous and the stigmata are yellow rather than white (MBGBI Vol 10). Larva feeds within stems and roots of Hog's Fennel, over-wintering as an egg.