Common wherever the foodplant occurs, on calcareous soils throughout the British Isles, less so in the north and not recorded north of Aberdeen (MBGBI Vol 3). In Hampshire and on the Isle of Wight fairly common and widely distributed. Wingspan 19-26 mm. Distinguished from
Orchard Ermine Y. padella and
Apple Ermine Y. malinellus by the white forewings with white terminal cilia. Larva feeds on Spindle and, in gardens, Evergreen Spindle, living gregariously within a silken web.