Home/Species/ Dwarf Contorted Suncup

Camissonia contorta

(Dougl. ex Lehm.) Kearney

Dwarf Contorted Suncup

G4Apparently Secure Found in 10 roadless areas NatureServe Explorer →

G4Apparently SecureGlobal Rank

UnknownThreat Impact

Identity

Unique IDELEMENT_GLOBAL.2.152030

Element CodePDONA030G0

Record TypeSPECIES

ClassificationSpecies

Classification StatusStandard

Name CategoryVascular Plant

Endemicoccurs (regularly, as a native taxon) in multiple nations

KingdomPlantae

PhylumAnthophyta

ClassDicotyledoneae

OrderMyrtales

FamilyOnagraceae

GenusCamissonia

Synonyms

Oenothera cruciata(S. Wats.) Munz

Other Common Names

plains evening-primrose (EN) Plains Evening-primrose (EN)

Concept Reference

Kartesz, J.T. 1994. A synonymized checklist of the vascular flora of the United States, Canada, and Greenland. 2nd edition. 2 vols. Timber Press, Portland, OR.

Conservation Status

Rank Method Rank calculation - Biotics v2

Review Date2025-03-24

Change Date1988-08-01

Edition Date2025-03-24

Edition AuthorsN. Ventrella (2025)

Threat ImpactUnknown

Range Extent200,000-2,500,000 square km (about 80,000-1,000,000 square miles)

Number of Occurrences81 - 300

Rank Reasons

Camissonia contorta is an annual forb occurring on sandy soils, flats, disturbed areas, grasslands, chaparral, and pinyon-juniper woodlands of western North America from British Columbia, Canada south through Nevada and California in the United States. Records of this species also exist from Arizona and need confirmation. There are an estimated 250 occurrences of this species, which are threatened by encroachment by invasive species (including scotch broom and European beach grass), stabilization of dunes, succession, recreation, herbivory, and other threats in some places. Little is known about trends, and monitoring populations is important to improving our understanding of the status of Camissonia contorta.

Range Extent Comments

Camissonia contorta occurs in western North America, from British Columbia, Canada south through Nevada and California in the United States (FNA 2021). Herbarium specimens collected near Sedona, Arizona have also been determined to be this species (for example, M. Licher 462 (ASC)) (SEINet 2025). Range extent was estimated using herbarium specimens, photo-based observations, and NatureServe Network occurrence data collected between 1994 and 2025 (RARECAT 2024, GBIF 2025, iNaturalist 2025, NatureServe 2025, SEINet 2025).

Occurrences Comments

By applying a 1 km separation distance to herbarium specimens, photo-based observations, and NatureServe Network occurrence data documented between 1994 and 2025, it is estimated that there are 250 occurrences rangewide (RARECAT 2024, GBIF 2025, iNaturalist 2025, NatureServe 2025, SEINet 2025).

Threat Impact Comments

In British Columbia, Canada, Camissonia contorta is threatened by encroachment by invasive species (including scotch broom and European beach grass), stabilization of dunes, succession, recreation, and herbivory (NatureServe 2025). Threats elsewhere are unknown.

Ecology & Habitat

Habitat

Camissonia contorta occurs on "sandy soil, slopes, flats, disturbed areas, grasslands, chaparral, [and] pinyon-juniper woodlands" from 0 to 2,700 m in elevation (FNA 2021).

Terrestrial Habitats

Forest EdgeWoodland - ConiferShrubland/chaparralGrassland/herbaceousSand/dune

Other Nations (2)

CanadaN1

Province	Rank	Native
British Columbia	S1	Yes

United StatesN4

Province	Rank	Native
Oregon	SNR	Yes
Washington	SNR	Yes
California	SNR	Yes
Idaho	SNR	Yes
Nevada	S3	Yes

Threat Assessments

Threat	Scope	Severity	Timing
Unknown/undetermined	—	—	—

Plant Characteristics

DurationANNUAL

Economic Value (Genus)No

Roadless Areas (10)

California (8)

Area	Forest	Acres
Camuesa	Los Padres National Forest	8,209
Fox Mountain	Los Padres National Forest	52,072
Greenhorn Creek	Sequoia National Forest	28,226
Mono	Los Padres National Forest	28,141
Rincon	Sequoia National Forest	54,610
Timbered Crater	Lassen National Forest	4,096
Wildhorse	Cleveland National Forest	1,483
Woolstaff	Sequoia National Forest	41,445

Nevada (2)

Area	Forest	Acres
Jobs Peak (NV)	Humboldt-Toiyabe National Forest	1,342
Rose - Alum Creek	Humboldt-Toiyabe National Forest	853

References (7)

Flora of North America Editorial Committee (FNA). 2021. Flora of North America north of Mexico. Vol. 10. Magnoliophyta: Proteaceae to Elaeagnaceae. Oxford Univ. Press, New York. xxiv + 456 pp.
Global Biodiversity Information Facility (GBIF). 2025. Global Biodiversity Information Facility (GBIF) data portal. Online. Available: https://www.gbif.org/ (accessed 2025).
iNaturalist. 2025. Online. Available: https://www.inaturalist.org (accessed 2025).
Kartesz, J.T. 1994. A synonymized checklist of the vascular flora of the United States, Canada, and Greenland. 2nd edition. 2 vols. Timber Press, Portland, OR.
NatureServe. 2025. NatureServe Network Biodiversity Location Data. NatureServe, Arlington, Virginia.
NatureServe's Rapid Analysis of Rarity and Endangerment Conservation Assessment Tool (RARECAT). 2024. Version: 1.1.1 (released Oct 01, 2024).
Southwest Environmental Information Network (SEINet). 2025. Collections Databases. Online. Available: https://swbiodiversity.org/seinet/collections/index.php (accessed 2025).

Camissonia contorta

Habitat

—