This well-known insect was first described on page 453 of
Thomas Say, "Descriptions of Coleopterous Insects collected in the late Expedition to the Rocky Mountains, performed by order of Mr. Calhoun, Secretary of War, under the command of Major Long. (Read October 22, 1823," Journal of the Academy of Natural Sciences of Philadelphia 3 (1824) 403-462.
Say placed this species in the genus Doryphora, and, as is so often the case in taxonomy, the species was later placed in another genus, in this case, Leptinotarsa.
The image was kindly supplied by the Clemson University Department of Entomology, Cooperative Extension Service.