The Cloudless Sulphur (Phoebis sennae) is a large, bright yellow butterfly in the family Pieridae, well-known for its vibrant coloration and wide distribution. It is a highly migratory species and a common sight in both urban and natural landscapes. The upper side of the wings is a brilliant lemon-yellow in males, while females are paler, often with small dark spots or faint markings. The underside is greenish-yellow or pale yellow with faint brown spots, providing camouflage when the butterfly is at rest.