Sulphur (Phoebis sennae) females are yellow or white
and the outer edges of both wings have irregular black borders,
the upper forewing has a dark spot in a cell. This is one case
where the female is more colorful than the males which are lemon
yellow with no markings..
This is the most common large sulphur and the males patrol with
a rapid, powerful flight, searching for receptive females. Then
the eggs are laid singly on young leaves or flower buds of partridge
pea plants, a prairie wildflower and the host plant for the
These rapid fliers are commonly found in open spaces, brushy
areas, gardens, deserts, and along seashores. They can be seen
throughout most of the United States and during the spring and
autumn as far north as Maine, Montana, and northern California.