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Close-up photo of live Queen Alexandra's Sulphur (Colias alexandra) ventral view

Mtn Lakes Wilderness, Klamath Co, August 15

Alexandra's Sulphur

Colias alexandra

Size: 2.0 - 2.8 inches wingspan

Key ID features:  Larger than any other Oregon sulphur, with more pointed FW. Below HW discal spot is white (not pearly) with no satellite spot, often unrimmed. Below HW has heavy black overscaling, giving strong green cast.

Similar species:  Clouded Sulphurs are smaller and have double ring around discal spot on HW below. Western Sulphurs are smaller and often have brighter pink wing borders. Pink-edged Sulphurs have more rounded wings, lack black overscaling below and have bright pink wing borders.


Host plant: Various species in the pea family, especially Astragalus (milkvetch) and Medicago (alfalfa).

Habitat: Meadows, roadsides, dry steppe slopes and forest glades.

Range: Throughout eastern Oregon.

Season: mid-April to mid-September

Abundance: Common


Conservation Status: Secure

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