Oenothera flava ssp. taraxacoides
Oenothera flava (A. Nelson) Garrett ssp. taraxacoides (Woot. & Standl.) W.L. Wagner
Lavauxia taraxacoides Woot. & Standl.
Oenothera taraxacoides (Woot. & Standl.) Munz
Yellow Evening Primrose
This is the “dandelion subspecies” of yellow evening primose, so-called for the resemblance of its foliage to dandelion leaves.
Identification: You know you’re talking about an unusual plant when you can’t find much of anything about it online. Plants have a rosette of basal leaves reminiscent of dandelion leaves. Flowers emerge directly from the base on red stems. Flowers are yellow, about 1-1½" (2.5-3.8 cm) around, with four petals. Plants and flowers together are only about 8" (20 cm) tall.
Oenothera flava ssp. taraxacoides on the USDA Plants Database
Oenothera flava on SEINet—the Southwest Environmental Information Network
Oenothera flava ssp. taraxacoides on Northern Arizona Flora
Oenothera flava at the Lady Bird Johnson Wildflower Center
Oenothera flava subspecies flava on Wildflowers, Ferns & Trees of Colorado, New Mexico, Arizona, and Utah
Oenothera flava ssp. taraxacoides description by Thomas H. Kent, last updated 12 Oct 2018.