Wing span: Males 4.0 to 5.0 cm, females 4.5 to 6.0 cm.

Flight time: Multiple overlapping broods from early May through mid-November.

Status: Breeding resident.

Distinguishing features: This butterfly has orange wings with black borders that are generally wider than those of the Common Sulfur. Early spring adults are less orange and have considerably narrower black margins than adults from later broods. Significant portions of females in all broods are albinic, and these are difficult to distinguish from white Common Sulfur females. The relative widths of the black wing margins are often the only factors available to help distinguish these individuals.

Distribution and habitat: The orange Sulphur is one of the most abundant butterflies throughout the state. It is found in a wide variety of open habitats, including alfalfa fields and old pastures.

Natural History: Temperature is thought to be the factor that affects the proportion of albinic individuals in the population. Larvae consume alfalfa, vetch, and a variety of other legumes.