20.007 BF409b
Argyresthia cupressella
Walsingham, 1890
Wingspan 8-9 mm.
Originating from North America, this adventive species has evidently been introduced with its foodplants, and was first found in the British Isles in Suffolk in 1997. Like several other microlepidoptera feeding on ornamental conifers, it is expanding its range quite dramatically.
The larvae feed on cypress (Chamaecyparis and Cupressocyparis) and juniper (Juniperus), feeding internally on the leaves and young shoots. In spring affected shoots turn brown and are quite noticeable.
In Britain the adults are on the wing in June and July.