The Yellow Shell (Camptogramma bilineata) is a highly variable species (wingspan: 20–25 mm), with examples ranging from bright yellow to dark brown, and also variable in size.

1st & 2nd photo: In my yard, Hilversum, The Netherlands, 7 September 2017
3rd & 4th photo: Zanderij Crailo, Hilversum, The Netherlands, 24 June 2013