Once the male has found a receptive female through rapid flight, mating occurs. The female deposits her eggs singly on the leaves and/or blooms of host plants, from which caterpillars will hatch and feed upon the plant. In the chrysalis stage, a silk thread helps to suspend the cocoon from the plant stem. From the cocoon, a mature Cloudless Sulphur emerges.
Cloudless Sulphurs are commonly found in open areas with abundant sunlight, ranging from roadsides to fields, pastures, and fallow agricultural lands. They may be found feeding upon Thistle, Morning Glory, Sennas, and Clover. The adults are especially attracted to red-flowering Geraniums as a nectar source. The scientific name of the butterfly is partially derived from the Greek language as well as one of its food sources; Phoebis meaning "pure" or "radiant," and sennae corresponding to the Senna plant which it consumes as a caterpillar.
Adults are found on both shores of the United States, migrating in large swarms throughout California into the southern states and the eastern coastal regions. Migration occurs throughout the year wherever warm weather may be found. The Cloudless Sulphur is difficult to capture due to its strong, rapid flight and unusual perching behavior, rarely perching with its wings open. The Cloudless Sulphur is a harmless insect to plant life that adds bright color, making it a welcome visitor to any garden.
Kristen Jacob, Agricultural Education
Carrie Meetze, Agricultural Education
Insect Biology and Diversity – Fall 2003
