Discovery and lectotype designation of Longitarsuscalifornicus (Motschulsky) (Coleoptera, Chrysomelidae, Galerucinae, Alticini).

The lectotype of Longitarsuscalifornicus (Motschulsky, 1845) is designated, described, and illustrated. An illustrated key to eight light-colored Longitarsus species known to occur in the western United States is presented. A brief history of Russian entomological collecting in North America during the first half of 19 th century, with specimens preserved in Zoological Museum of Moscow University, Moscow and Zoological Institute, St. Petersburg, is provided.