Orange Sulphur (University of Arizona Pollinator Field Guide)

Orange Sulphur

Colias eurytheme

Who am I? ²

Hiya there! I am Colias eurytheme, the Orange sulphur or the Alfalfa butterfly. As cute and yellow as I may seem, I can sometimes be a serious pest to alfalfa. But our numbers are often controlled by natural predators such as parasitoid wasps, lady beetles, assassin bugs, and more! Hopefully you don't catch me eating away your alfalfa field!

Quick facts ²

Common name: Orange sulphur

Scientific name:Colias eurytheme (Boisduval 1852)

Family: Pieridae - Coliadinae

Characteristics:

Wing span: 1 3/8 - 2 3/4 inches (3.5 - 7 cm)
Coloration / patterns can vary
Upperside: yellow with orange hues, wide black border
Underside: yellow, hindwing has a silver / light spot with a red border (sometimes has a smaller spot nearby)
Can have pink edging
Males tend to have more angled forewings in the summer
Sometimes has a "white form"

Host plant: Primarily alfalfa (Medicago sativa), but can also be white clover (Trifolium repens), and white sweet clover (Melilotus alba)

Nectar plant: Variety of flowers, includes alfalfa, clovers (Trifolium), milkweeds (Asclepias), sunflower (Helianthus hirsutus), asters (Aster), and goldenrods (Solidago)

Distribution: Appears throughout most of the United States, less frequent in Florida; S of Canada to central Mexico

Flight times: Most likely to be seen Jun - Oct., and Mar.-Nov. in warmer southern regions. See seasonality: https://www.inaturalist.org/taxa/58532-Colias-eurytheme

Read more about us here: https://butterfly.ucdavis.edu/butterfly/colias/eurytheme

Where can you find me on campus? ²

So far, Orange sulphurs have only been found lingering around the boundaries of campus. An observation north of campus shows one feeding on a Red Bird of Paradise from the Fabaceae family, which is the family most of its preferred nectar plants reside in. These flowers can primarily be found nearby the 2nd St. garage.