The Orange Sulphur is about an inch and half in size with distinct open dots on the underwing. Most in this sulphur family are shades of white, yellow, or orange. They can be found from mountains to deserts, in open spaces. They are also known as Alfalfa butterfly because they are found often around alfalfa fields. The caterpillars feed on various pea and legume plants. I found this one near a duck pond in northern Arizona.