Calochortus superbus is a species of flowering plant in the lily family known by the common name superb mariposa lily. It is endemic to California, where it is a common member of the flora in several types of habitat statewide. It is a perennial herb growing up to 40 to 60 centimeters tall with a basal leaf up to 30 centimeters long which withers by flowering. The inflorescence is a loose cluster of 1 to 3 erect, bell-shaped flowers. Each flower has three sepals and three petals all up to 4 centimeters long and blotched with yellow at the bases. There is generally a darker spot within the yellow area, and the base color of the segments may be white to light purple or solid yellow. The fruit is an angled capsule 5 or 6 centimeters long. This plant resembles Calochortus luteus, a chief discriminant being the oval to crescent shaped nectary of C. luteus compared to the squarish nectary of C. superbus.