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Prenanthella exigua

(Gray) Rydb.

Brightwhite

G5Secure Found in 4 roadless areas NatureServe Explorer →
G5SecureGlobal Rank
UnknownThreat Impact
Identity
Unique IDELEMENT_GLOBAL.2.137466
Element CodePDAST7J010
Record TypeSPECIES
ClassificationSpecies
Classification StatusStandard
Name CategoryVascular Plant
Endemicoccurs (regularly, as a native taxon) in multiple nations
KingdomPlantae
PhylumAnthophyta
ClassDicotyledoneae
OrderAsterales
FamilyAsteraceae
GenusPrenanthella
Other Common Names
Desert Prenanthella (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 Date2025-12-22
Change Date2025-12-22
Edition Date2025-12-22
Edition AuthorsSoteropoulos (2025)
Threat ImpactUnknown
Range Extent200,000-2,500,000 square km (about 80,000-1,000,000 square miles)
Number of Occurrences> 300
Rank Reasons
Prenanthella exigua is a wide-ranging annual herb found in sandy, gravelly, or clay soils, desert washes and open slopes to sagebrush-juniper steppes and woodlands. It occurs in western North America from southeastern Oregon, southwestern Idaho, and Colorado south through western Texas and southeastern California in the United States to Baja California and Sonora in northern Mexico. Little is known about threats or trends, but with a large range extent and over 300 occurrences this species is considered secure.
Range Extent Comments
Prenanthella exigua occurs in western North America from southeastern Oregon, southwestern Idaho, and Colorado south through western Texas and southeastern California in the United States to Baja California and Sonora in northern Mexico (FNA 2006, Jepson Flora Project 2025). Range extent was estimated to be over 850,000 square kilometers using herbarium specimens and photo-based observations documented between 1994 and 2025 (GBIF 2025, iNaturalist 2025, RARECAT 2025, SEINet 2025).
Occurrences Comments
By applying a 1 km separation distance to herbarium specimens and photo-based observations documented between 1994 and 2025, it is estimated that there are over 300 occurrences rangewide (GBIF 2025, iNaturalist 2025, RARECAT 2025, SEINet 2025).
Threat Impact Comments
There is insufficient data, including anecdotal accounts, to understand threats for this species.
Ecology & Habitat

Habitat

Prenanthella exigua grows in sandy, gravelly, or clay soils, desert washes and open slopes to sagebrush-juniper steppes and woodlands (FNA 2006, Jepson 2025).

Reproduction

This species flowers from March to June (FNA 2006).
Terrestrial Habitats
Forest/WoodlandWoodland - ConiferWoodland - MixedShrubland/chaparralDesert
Other Nations (1)
United StatesN5
ProvinceRankNative
New YorkSNANo
NevadaS4Yes
CaliforniaSNRYes
UtahSNRYes
IdahoS2Yes
New MexicoSNRYes
ColoradoS1Yes
TexasS1Yes
OregonS1Yes
ArizonaSNRYes
Threat Assessments
ThreatScopeSeverityTiming
Unknown/undetermined———

—

Plant Characteristics
DurationANNUAL
Economic Value (Genus)No
Roadless Areas (4)
California (4)
AreaForestAcres
Birch CreekInyo National Forest28,816
Black CanyonInyo National Forest32,421
PaiuteInyo National Forest58,712
Soldier CanyonInyo National Forest40,589
References (7)
  1. Flora of North America Editorial Committee (FNA). 2006a. Flora of North America north of Mexico. Vol. 19. Magnoliophyta: Asteridae, part 6: Asteraceae, part 1. Oxford University Press, New York. xxiv + 579 pp.
  2. Global Biodiversity Information Facility (GBIF). 2025. Global Biodiversity Information Facility (GBIF) data portal. Online. Available: https://www.gbif.org/ (accessed 2025).
  3. iNaturalist. 2025. Online. Available: https://www.inaturalist.org (accessed 2025).
  4. Jepson Flora Project (eds.) 2025. Jepson eFlora. Online. Available: https://ucjeps.berkeley.edu/eflora/ (accessed 2025).
  5. 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.
  6. <p>NatureServe's Rapid Analysis of Rarity and Endangerment Conservation Assessment Tool (RARECAT). 2025. Version: 2.1.1 (released April 04, 2025).</p>
  7. Southwest Environmental Information Network (SEINet). 2025. Collections Databases. Online. Available: https://swbiodiversity.org/seinet/collections/index.php (accessed 2025).