Larinus planus is a weevil, an insect of the Curculionidae family. It is native to Europe, and is also common in North America. Both the larvae and adults feed on flower buds, mostly of thistles. They are oval shaped, dark brown or black, and about 5-10 millimeters long.
Larinus planus has been used to control the Canada thistle. 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.
- It is also known as Larinus carlinae. "Larinus planus (Fabricius, 1792)". Natural History Museum. The Trustees of The Natural History Museum, London. Retrieved 30 January 2019.
- "Larinus planus". Plant Parasites of Europe. W.N. Ellis, Amsterdam, The Netherlands. Retrieved 30 January 2019.[dead link]
- "Larinus planus". Ministry of Forests, Lands, and Natural Resource Operations. Province of British Columbia, Ministry of Forests. 17 May 2007. Archived from the original on 30 January 2019. Retrieved 30 January 2019.
- Operational Field Guide to the Propagation and Establishment of the Bioagent Larinus Planus (PDF). Province of British Columbia, Ministry of Forests. May 2001. Archived from the original (PDF) on 2018-11-13. Retrieved 2019-01-30.
- Louda, Svaa M.; O'Brien, Charles W. (June 2002). "Unexpected Ecological Effects of Distributing the Exotic Weevil, Larinus planus (F.), for the Biological Control of Canada Thistle" (PDF). Conservation Biology. 16 (3): 717–727. doi:10.1046/j.1523-1739.2002.00541.x.[permanent dead link]
- Havens, Kayri; Jolls, Claudia L.; Marik, Julie E.; Vitt, Pati; McEachern, A. Kathryn; Kind, Darcy (October 2012). "Effects of a non-native biocontrol weevil, Larinus planus, and other emerging threats on populations of the federally threatened Pitcher's thistle, Cirsium pitcheri". Biological Conservation. 155: 202–211. doi:10.1016/j.biocon.2012.06.010.