Oenothera deltoides ssp. howellii

Common Names:
Antioch Dunes evening-primrose
(Munz) W. Klein
Growth Habit:
CPC Number:
Profile Contributors:
Fully Sponsored

Reference Links

ITIS - Tropicos - USDA Plants - Fish & WildLife

Participating Institutions

The following Participating Institutions are custodians for this species in the CPC National Collection:
Regional Parks Botanic Garden
Rancho Santa Ana Botanic Garden

The conservation of Oenothera deltoides ssp. howellii is fully sponsored.


In 1984 a humpback whale beached itself on the dunes in the Antioch Dunes National Wildlife Refuge. Thousands of people came to see the animal, using the dunes to get the best view and, unfortunately, killing a number of endangered plant species growing there by trampling them to death. One of the species that fared the worst during this time was another National Collection species, Erysimum capitatum var. angustatum. Fortunately for the Antioch Dunes evening primrose, however, the human-caused disturbance actually allowed it to flourish.

This evening primrose is a much-branched perennial herb that produces showy, white flowers from March to September, and has grayish toothed or divided leaves. Because of its beauty, this primrose was chosen to be one of four endangered plants to be depicted in a set of stamps issued in 1979. (USFWS 1979c)

Distribution & Occurrence


Conservation, Ecology & Research