Oenothera longissima

Oenothera longissima
Conservation status
Apparently Secure  (NatureServe) [1]
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Clade:	Angiosperms
Clade:	Eudicots
Clade:	Rosids
Order:	Myrtales
Family:	Onagraceae
Genus:	Oenothera
Species:	O. longissima
Binomial name
Oenothera longissima Rydb.
Synonyms [2]
Oenothera clutei

Oenothera longissima is a species of flowering plant in the evening primrose family known by the common name longstem evening primrose. It is native to the southwestern United States, where it grows in relatively moist areas in scrub and woodland habitat. This is a biennial herb producing a tall, erect stem known to well exceed 2 meters in height. The widely lance-shaped leaves may be 22 centimeters in length and may have slight teeth along the edges. The inflorescence is a spike of showy large flowers. Each has yellow petals which may be more than 6 centimeters in length and fade orange or red with age. The fruit is a lance-shaped capsule up to 5.5 centimeters long.

Taxonomy

Oenothera longissima was scientifically described and named by botanist Per Axel Rydberg in 1913. It is part of the genus Oenothera in the Onagraceae family. The species has no accepted subspecies or varieties, but it has 4 synonyms. ^[2]

Table of Synonyms ^[2]

Name	Year	Rank	Notes
Oenothera cluteiA.Nelson	1922	species	= het.
Oenothera longissima subsp. typicaMunz	1949	subspecies	≡ hom., not validly publ.
Oenothera longissima var. clutei(A.Nelson) Munz	1949	variety	= het.
Oenothera longissima subsp. clutei(A.Nelson) Munz	1949	subspecies	= het.
Notes: ≡ homotypic synonym  ; = heterotypic synonym

References

1. NatureServe (5 September 2025). "Oenothera longissima". NatureServe Explorer. Arlington, Virginia. Retrieved 13 September 2025.
2. "Oenothera longissima Rydb". Plants of the World Online . Royal Botanic Gardens, Kew . Retrieved 13 September 2025.

External links

• Jepson Manual Treatment