Borowiec L. (200_-2013) Chrysomelidae: The leaf beetles of Europe and the Mediterranean subregion (checklist and iconography)
An excellent guide with a complete illustrated list of European taxa with distribution data, compiled and maintained by a wold's top chrysomelid expert. The source is increasingly relevant to our area because of the growing number of Palearctic leaf beetles showing up and establishing in North America.
a simplified key adapted by C.G. Majka from(1)
NB: Use the key with utmost caution beyond the indicated area, since adjacent areas (e.g. QC, ON, NY...) have much richer Calligrapha faunas
[Online] Guide to Palearctic flea beetle genera, by Alexander S. Konstantinov and Natalia J. Vanderberg
Nice online key to genera of Palearctic flea beetles; also can be used as a key to the Nearctic genera I've found: http://www.sel.barc.usda.gov/Coleoptera/fleabeetles/fleas.htm (Authors are at the Systematic Entomology Laboratory, USDA-ARS.)
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