Stebbinsoseris heterocarpa (syn. Microseris heterocarpa) is a species of flowering plant in the aster family known by the common name grassland silverpuffs. It is native to southwestern North America, where it can be found in various areas of California, and parts of Arizona and northern Mexico. It grows in open habitat in chaparral, woodlands, grasslands, desert, Sierra foothill, and inland canyons. Stebbinsoseris heterocarpa is variable in morphology. In general, it is an annual herb with a basal rosette of large leaves. The inflorescence arises on a tall peduncle bearing a solitary flower head. The head is lined in hairless phyllaries and contains many ray florets, often over 100, in shades of yellow or white. The fruit is an achene with a brown, gray, blue, or purple body tipped with a pappus of five long, spreading scales, the whole unit measuring 1 or 2 centimeters. This species is suspected to be a hybrid between Microseris douglasii and Uropappus lindleyi which may have evolved independently, possibly three times.