Wikipedia Article About Buttercup squash on Wikipedia Four species of the genus Cucurbita are called squash or pumpkins rather indiscriminately. C. maxima includes the large winter squashes (such as Hubbard and Banana) and some large pumpkins, and numerous smaller varieties such as Buttercup and Mooregold. On this species the peduncle (fruit stem) is spongy and swollen, not ridged.