The Pink-edged sulphur (Colias interior) is a species of North American butterfly in the Pieridae family.
Can be confused with small specimens of the Giant Sulphur (C. gigantea), but interior has a smaller underside discal spot, and the overall shape of the forewings is more rounded than pointy. In the mountains where the Pink-edged occurs together with the Pelidne, the pink wing fringe of interior is more pronounced, and the under- and upper side is not strongly suffused with black scales as in Pelidne.
The Pink-edged Sulphur is a typical boreal species, occuring from the eastern seaboard west to BC south to Oregon and Montana. In the eastern US, it is found only in the northermost states (Opler 1999).
Open woodlands (particularly pine) with a blueberry understory.
Non-Migrant: No. All populations of this species make significant seasonal migrations.
Locally Migrant: No. No populations of this species make local extended movements (generally less than 200 km) at particular times of the year (e.g., to breeding or wintering grounds, to hibernation sites).
Locally Migrant: No. No populations of this species make annual migrations of over 200 km.
Not of concern.