Larinus planus
Larinus planus has been used in North America to control the creeping thistle, a weed from Europe. It has spread to other plants. In 2000, it was found eating Cirsium undulatum. This is a thistle native to western Colorado and eastern Utah. Later research found that it had reduced the amount of seeds produced by the native thistle. It has also been found to have a bad effect on Cirsium pitcheri.