Galerucella calmariensis (Linnaeus, 1767)
black-margined loosestrife beetle
The larvae live, like the ones of G. pusilla, at the undersides of the leaves, causing extensive window feeding. The larvae of both species seem to be indistinguishable. Rheinheimer & Hassler write that the adults of calmariensis are larger and more convex, yellowish red (rather than light brown) and have a broad black median length line on the pronotum.
One to four generations; hibernation as imago.
distribution within Europe
Like G. pusilla employed successfully in the biological control of the introduced Lythrum salicaria in North America.
Rheinheimer & Hassler (2018a), Wilson, Schwarzlaender, Blossey & Bell Randall (2004a).