Cucurbita moschata is a species originating in either Central America or northern South America. It includes cultivars known as squash or pumpkin. C. moschata cultivars are generally more tolerant of hot, humid weather than cultivars of C. maxima or C. pepo. They also generally display a greater resistance to disease and insects, especially to the squash vine borer. Commercially made pumpkin pie mix is most often made from varieties of C. moschata. The ancestral species of the genus Squash were present in the Americas before the arrival of humans. Evolutionarily speaking the genus is relatively recent in origin as no species within the genus is genetically isolated from all the other species. C. moschata acts as the genetic bridge within the genus and is closest to the genus' progenitor.
All species of squashes and pumpkins are native to the Western Hemisphere. C. moschata, represented by such varieties as Cushaw and Winter Crookneck Squashes, and Japanese Pie and Large Cheese Pumpkins, is a long-vining plant native to Mexico and Central America. This species and C. pepo apparently originated in the same general area, Mexico and Central America. Both are important food plants of the original people of the region, ranking next to maize and beans. The flowers and the mature seeds, and the flesh of the fruit are eaten in some areas.
Before the arrival of Europeans, C. moschata and C. pepo had been carried over all parts of North America where they could be grown. Still, they had not been carried into South America as had beans, which originated in the same general region. They were generally grown by indigenous people all over what is now the United States. Many of these peoples, particularly in the west, still grow a diversity of hardy squashes and pumpkins not to be found in commercial markets.