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Orange Sulfur Butterfly

Colias eurytheme


Medium-sized yellow butterfly, as pictured, with two distinctive spots on the underwing, as shown in the first photo above. I originally thought this butterfly to be a Southern Dogface (Colias cesonia)...but on further research I determined this to be an Orange Sulfur...markings are in line with the 2nd forewing photo above.


These butterflies are very common in southern Nevada metro areas, and in the surrounding Mojave Desert. They adapt well to areas with gardens and lawns…and are just as at home in the desert.


Orange Sulfurs reach their peak numbers in July and August, when their favorite nectar sources are available. They favor prairie clover, and many flowering plants such as that pictured.

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Jim Nelson
Jim Nelson 2 years ago

Thanks, Daniele...I have done some more research, and am now convinced this is an Orange Sulfur (Colias eurytheme). The forewing exactly matches that in my photo, so I was off base at all levels with this one. Nothing seemed to fit and I should have done more research before setting this posting. I am editing this to bring it current with the revised spotting. Your input is appreciated!

DanielePralong 2 years ago

Hi Jim! If you search the Organisms page for the scientific name Colias cesonia, you find one spotting:
I hope someone more familiar with American butterfly species can confirm ID for both spottings. Colias can be a tricky genus.

Jim Nelson
Spotted by
Jim Nelson

Nevada, USA

Lat: 36.10, Long: -115.25

Spotted on Aug 2, 2017
Submitted on Aug 23, 2017

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