Natural History

Cloudless Sulfur Butterflies are large yellow butterflies with a wing span of 1 7/8 - 2 1/2 inches. They are strong flyers and can migrate long distances. Males are usually solid yellow above and below and have few visible markings. Females may be yellow, orange-yellow or white, and they have a faint dark border on the upper surface of their wings.
 

Cloudless Sulfur Butterflies live in open sunny areas including parks, yards, gardens, beaches, road edges, abandoned fields, and scrub. Females lay eggs singly on the leaves or buds of host plants (Cassia species in the pea family) on which caterpillars later feed. Adults fly from late March through early January in Arizona and will feed on the nectar from many different flowers with long tubes including cordia, bougainvilla, cardinal flower, hibiscus, lantana, and wild morning glory.