Numbers
Nomina Insecta Neartica only lists 1 North American species,
iole.
Identification
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.
Range
Resident in Guatemala north to peninsular Florida and the Southwest. Cannot survive cold winters, therefore every summer re-colonizes through the Great Plains to southeast Washington, southeast Idaho, Wyoming, and Minnesota.
Habitat
Open, dry places including coastal flats, weedy fields, grasslands, road edges, meadows, and hillsides.
Food
Low-growing plants in the aster family (Asteraceae) especially shepherd's needle (Bidens pilosa), Spanish Needles, (Bidens alba), sneezeweed (Helenium), fetid marigold (Dyssodia), and cultivated marigold (Tagetes).
Life Cycle
Males patrol a few inches above the ground in low areas for females. Females lay eggs singly on leaves of host plant seedlings. Adults rest with wings closed and held perpendicular to the sun's rays to warm themselves.
Remarks
This is North America's smallest sulphur
(1)
Print References
"Butterflies of North America (Kaufman Focus Guides)" pp. 70-71
(1)
Glassberg, p.64, plate 8
(2)Internet References
Dallas Butterflies has some great photos of pinned specimens.
Nature Photographer, Randy Emmit, also has some
nice shots.