2 Bright-Yellow Poppy Species Identified in Western US
This is a close up of Eschscholzia papastillii.
Credit: Shannon M. Still

Two new species of bright-yellow poppies have been discovered in U.S. deserts.

Both species, Eschscholzia androuxii and Eschscholzia papastillii, belong to the same genus as the California poppy (Eschscholzia californica), the state flower of California. The newly discovered plants can be found in the deserts of California and Arizona.

"What is interesting about these new species is 

An image of Eschscholzia androuxii.
An image of Eschscholzia androuxii.
Credit: Shannon M. Still

that, while people have been collecting these plants for decades, they were not recognized as something different," study author Shannon Still, a postdoctoral researcher at the Chicago Botanic Garden, said in a statement. "They were always confused for existing species."

E. androuxii is quite rare, and found over only a small range, whereas E. papastillii is widely distributed.

There may be other desert plant species that are also understudied, Still said.

To determine that the plants were, indeed, new species, Still compared specimens he gathered from the field with preserved specimens in California plant collections.

"This work highlights the value that herbarium collections play in cataloging, understanding and conserving our biological diversity," he said in a statement.

The study was published March 11 in the journal PhytoKeys.

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