North American Distribution of Coccinella septempunctata (Coleoptera: Coccinellidae) and Its Mass Appearance in Coastal Delaware

The Palearctic sevenspotted ladybeetle, Coccinella septempunctata L., well established in North America, has now spread through parts of five Canadian provinces and 34 contiguous eastern states of the United States. In southern coastal Delaware in June 1984, a mass appearance of C. septempunctata occurred where wind systems brought masses of these beetles into the area from unknown sources and dropped them into the seawater. Large numbers then washed up on beaches, and some surviving beetles annoyed vacationers and even bit some people. We speculate on the original establishment of this insect in North America. Presenting evidence previously overlooked, we add to speculation that early intentional releases led to establishment of this predator in North America. However, accidental importation on transoceanic ships cannot be ruled out.