Though predominantly a coastal insect [...] as Robson implied, it is by no means confined to this habitat [...] In Durham there are [...] several inland records. TCD has taken it quite commonly at Chester-le-Street, R. Henderson found it in some numbers at High Spen, and I. Findlay took it regularly in the trap as far west as Middleton-in-Teesdale. Dark forms predominates and in the more extreme specimens the hindwings are also covered by a uniform dusky shade. [...] The flight period is slightly more restricted than that of the previous species, lasting typically from mid-July to late August.