Peponapis pruinosa is a species of solitary bee in the tribe Eucerini, the long-horned bees. Its common name is eastern cucurbit bee. It may be called the squash bee, but this name can also apply to other species in its genus, as well as the other squash bee genus, Xenoglossa. This bee occurs in North America from the East Coast of the United States to the West Coast and into Mexico. It is an oligolege, specializing on a few host plants, the squashes and gourds of genus Cucurbita. Its range expanded as human agriculture spread throughout North America and squash plants became more abundant and widespread. It may also have spread naturally as the range of its favored wild host plant Cucurbita foetidissima expanded.