Clouded sulphur butterfly or Colias philodice
Clouded sulphur or Colias philodice have three broods in Eastern Washington that take flight May through October, with spring and fall forms tending to be smaller and less conspicuously marked. Apart from an orange spot on the dorsal hindwing, this butterfly never has orange scaling like the orange sulphur or its hybrids, and its wings don't reflect ultraviolet light.
This butterfly is more likely than other species to be found in farm country or in the city where its host plants are common, including legumes such as alfalfa, vetch, clover and peas. In can also get by on locoweed and lupine.
Males are clear yellow with thin, solid black edging on the upper wing surface while females have two forms -- yellow with uneven black edging enclosing yellow spots and a greenish white form. The clouded sulphur and orange sulphur are related and may interbreed. Orange sulphur has a white female form which can be difficult to distinguish, but the clouded sulphur never has orange-tinted wings.
Clouded sulphur may be identified by a row of dark spots on the underside, a pearly spot on the hindwing encircled with double rings, usually with a satellite spot, and no orange wash.
Clouded sulphur butterfly on moist sand - August
Clouded sulphur taking flight - October
