Dainty Sulphur

Description:

This little butterfly had about a 3 cm wingspan. "This is North America's smallest sulphur." It appears that it was ovipositing on a plant but it's not a known host plant. It kept going back and forth between two plants. "Small, with elongated forewings. Upperside yellow with black markings, female with more extensive black than male. White form very rare. Underside of forewing with orange or yellow patch at base of wing and black spots at outer wing edge. Winter form has dusty green hindwing, summer form hindwing is pale yellow." - BugGuide

Habitat:

Pacific swampfire? Glasswort? along trail next to a Lagoon. They prefer "open, dry places including coastal flats, weedy fields, grasslands, road edges, meadows, and hillsides." - BugGuide

Notes:

I'm waiting for a response from BugGuide as to what this butterfly was doing with its abdomen if it's not ovipositing as suggested.