Description: Wingspan 34-38mm. Forewings white with a small discal spot; the basal patch is deep blue with a brown marginal edge. There is a small dark patch at the costa towards the apex of the forewings. The outer margins are suffused with a greyish blue colour. From mid-June to early August.

Irish Distribution: Widely distributed throughout most counties, but not commonly encountered in any significant numbers. Frequently recorded from many of the fens and bogs around north Armagh such as, Brackagh Moss, NNR, Argory Moss and Peatlands Park. Many of the recent records are from Fermanagh, where increased fieldwork has discovered it at many sites.

Ecology: A large attractive moth that favours woodland rides and clearings, although it does occur on many bogs that have adjacent woodland. Adults are attracted to light but appear occasionally and always in small numbers. The larvae can be found from July to September on Bramble Rubus fruticosus, Hazel Corylus avellana and Raspberry Rubus idaeus. It overwinters as a pupa.

Key Identification Features:

• White wings
• Dark patches at the apex of the forewings
• Dark basal patch
• Hindwings pale white with a brownish band at the outer margin

Distribution Map from NBN: Mesoleuca albicillata at National Biodiversity Network mapping facility, data for UK.

iNaturalist: Mesoleuca albicillata at iNaturalist World Species Observations database.