Although actually a small insect, it may cause considerable damage to these crops. There are actually two types of cucumber beetles, the spotted and the striped. The striped cucumber beetle is most common in our area, and has three black stripes down its back. Flip it over and the rear portion of the underside should be black. If it's yellow, it's the western corn rootworm beetle, not considered a serious pest of cucumbers or melons.
Cucumber beetles spell trouble for cucumbers and related plants in two ways.
First, they directly consume leaves, which is especially a problem when plants are small. Even more damaging, however, is the fact cucumber beetles can carry bacterial wilt disease, a serious problem of cucumber, muskmelon, and watermelon. Infected plants suddenly wilt and die after the beetles have been feeding. If the beetle is carrying the bacteria, the plant becomes infected. Symptoms may not show until later into the season, when the vines wilt and die.