Coryphantha are small cacti from Mexico and the Southwest of the USA. They are closely-related to the large genus Mammillaria, and some are cold hardy. The name Coryphantha is from the Greek and means "flowering on the top"; the flowers appear in the youngest growth, which is in the center on top of the plant. The flowers are yellow, white or pink. The fruits are green and juicy, with dried flower remnants attached, the seeds are brown, smooth, with reticulate testa.