Euchloe ausonides, the large marble or creamy marblewing, is a species of butterfly that occurs in western North America. It lays eggs on the terminal flower buds of a variety of plants in the mustard family, including introduced Eurasian species, and the larvae feed on the buds, flowers and fruit of these plants. In California, it has witnessed population declines since the 1980s, especially in the Central Valley and the Bay Area. In Washington, subspecies the island marble butterfly (Euchloe ausonides ssp. insulanus) was listed as an endangered species under the Endangered Species Act in 2020.

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