The Large Wall Brown is much more widespread and more frequently encountered than its localised mountain cousin the Northern Wall Brown (L. petropolitana).
It is larger and paler than the Northern Wall Brown, and lacks the discal wavy transverse line across the centre of the upperside of the hindwing, clearly present in the Northern Wall Brown.
Females are more orange than the males but should not normally be mistaken for the smaller and much more orange Wall Brown (L. megera), which is common and widespread in Bulgaria. The Wall Brown has very clearly defined netting markings on the forewing in both sexes. This netting pattern is at best indistinct in the Large Wall Brown (more apparent in females) and hardly visible on the Northern Wall Brown.
We have recorded it from low altidues (<200m) to 1600m and higher, and very occasionally to over 2000 masl, however these may be wanderes taken up the mountain by wind currents.
Recorded in 43 (2.3%) of the 1900 10km squares of Bulgaria.
Last recorded in June 2019
Recorded date range (Adult): 09 May to 11 August