Marbled Green Nyctobrya muralis
Wingspan 27-34 mm.
A local species, occurring mainly on the coasts of southern England and south Wales, occasionally reaching inland, usually on calcareous soils. Also in southern Ireland.
A number of forms have been described, but many of these overlap in appearance and the situation is rather complex.
The adults are on the wing during July and August, and rest during the day on rocks and walls covered with lichen.
The caterpillars feed on lichens in these habitats, especially Diploica canescens.