Food Plant: Artemisia vulgaris (Mugwort), A.absinthium (Wormwood), Achillea millefolium (Yarrow), Tanacetum vulgare (Tansy) and Leucanthemum vulgare (Ox-eye Daisy)

Egg: Laid on the uderside of a leaf

Mine: September - June

Notes: The larva starts feeding in the autumn and attaches itself low down on the stem during the winter. The larva continues feeding in April and may be found on the lower leaves in Mugwort. The final case is around 10mm long and slightly thickened in the middle. The larvae my be distinguished from C.follicularis as they have a pale head and concolorous prothoracic plate, with a cresentic line, whereas follicularis has a blackish or brown prothoracic plate. C.gardesenella has two spots on the posterior of the prothoracic plate, which distinguishes it from C.trochilella. May be locally common and fond in drier habitats. Achillea millefolium with browned leaflets left by feeding larvae. A larval case is just visible at the base of the plant in the centre of the image.

Data: 02.v.2022, Frilford Heath, Oxfordshire, VC22, adult emerged 12.vii.2022, gen det Peter Hall

Image:© Will Langdon