Spotted Cucumber Beetle (Diabrotica undecimpunctata). A handsome beetle, but one not to be welcomed to your garden if you are dedicated to growing melons, gourds, squash or cucumbers. They are specialists on these crops, which as a group are called, cucurbit crops. Spotted Cucumber Beetles will also feed on other plants in addition to cucurbits.
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Beetles are in the order Coleoptera. They have protective, usually hardened, wing covers that enclose the wings that are used for flight. That is what you see here, the yellow wing coverings with 12 black spots, which are called elytra.