ABH: 16.005
BF: 428
Family: Yponomeutidae
Subfamily: Yponomeutinae
Taxon: Yponomeuta rorrella
Authority: (Hübner, 1796)
Vernacular: Willow Ermine
Account: As a resident, favours coastal locations in southern and eastern counties, where the food plants occur, but most frequently encountered as a migrant, when it can be abundant; as such, there are numerous records from South Hampshire, but less frequent in the north. Surprisingly, un-recorded on the Isle of Wight until 2012, when a major influx saw 8 individuals reported, and has been annual since.
Wingspan 19-24 mm. Very difficult to separate from Orchard Ermine Y. padella and Apple Ermine Y. malinellus, but grey wash generally restricted to dorsal half of forewing: if this is not clear, then records need to be aggregated as 'Yponomeuta sp.' Larva feeds on White Willow and Goat Willow, living gregariously within a silken web.
Wingspan: 19 — 24 mm
Surrey Flight Period: 28 Jun (2025) — 7 Aug (2010)
Foodplant: Salix alba (White Willow), Salix cinerea (Grey Willow).
Status: Local
UK BAP:
WCA:
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Verification Grade: 2 — Care needed to identify, an image may be required 🤔
Further Information: https://www.ukmoths.org.uk/species/yponomeuta-rorrella/
* Based on adult records only.
Records: 12
Individuals: 20
Earliest Year: 2010
Latest Year: 2025