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Home/Species/ Bolander's Monkeyflower

Diplacus bolanderi

(A. Gray) G.L. Nesom

Bolander's Monkeyflower

G4Apparently Secure Found in 13 roadless areas NatureServe Explorer →
G4Apparently SecureGlobal Rank
UnknownThreat Impact
Identity
Unique IDELEMENT_GLOBAL.2.1269261
Element CodePDSCR220T0
Record TypeSPECIES
ClassificationSpecies
Classification StatusStandard
Name CategoryVascular Plant
Endemicendemic to a single nation
KingdomPlantae
PhylumAnthophyta
ClassDicotyledoneae
OrderLamiales
FamilyPhrymaceae
GenusDiplacus
Synonyms
Mimulus bolanderiGray
Concept Reference
Flora of North America Editorial Committee (FNA). 2019. Flora of North America north of Mexico. Vol. 17: Magnoliophyta: Tetrachondraceae to Orobanchaceae. Oxford Univ. Press, New York. xxiv + 737 pp.
Taxonomic Comments
The Flora of North America (vol. 17 2019) expands the concept of Mimulus bolanderi (= Diplacus bolanderi) to include M. platylaemus, while Kartesz (1994) treats them as distinct and transfers to Diplacus.
Conservation Status
Rank Method Rank calculation - Biotics v2
Review Date2025-02-21
Change Date1990-01-16
Edition Date2025-02-21
Edition AuthorsSoteropoulos (2025)
Threat ImpactUnknown
Range Extent20,000-200,000 square km (about 8000-80,000 square miles)
Number of Occurrences81 - 300
Rank Reasons
Diplacus bolanderi is an annual herb in granite outcrops, openings in chaparral, and disturbed areas occurring in the western United States in southwestern Oregon south throughout California to the Western Traverse Ranges. There are over 125 occurrences that are potentially threatened by development, grazing, invasive species, and fire suppression. Little is known about trends, but with a large range extent and large number of occurrences, and no obvious intrinsic vulnerabilities, this species is considered apparently secure.
Range Extent Comments
Diplacus bolanderi occurs in the western United States in southwestern Oregon (Jackson County) south throughout California to the Western Traverse Ranges (FNA 2019, Jepson 2025). Range extent was estimated to be over 170,000 square kilometers using herbarium specimens, photo-based observations, and NatureServe Network occurrence data documented 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 over 125 occurrences rangewide (RARECAT 2024, GBIF 2025, iNaturalist 2025, NatureServe 2025, SEINet 2025).
Threat Impact Comments
Although threats are not widely documented, this species is potentially threatened by development, grazing, invasive species, fire suppression, and other threats in some places. However, their overall impact is likely negligible given the species' broad range, large number of occurrences, and no obvious intrinsic vulnerabilities.
Ecology & Habitat

Habitat

Diplacus bolanderi grows on "granite outcrops, slopes with decomposed granite soils," "burns, openings in chaparral, disturbed areas" (FNA 2019, Jepson 2025).
Terrestrial Habitats
Shrubland/chaparralBare rock/talus/scree
Other Nations (1)
United StatesN4
ProvinceRankNative
OregonS1Yes
CaliforniaSNRYes
Threat Assessments
ThreatScopeSeverityTiming
Unknown/undetermined———

—

Plant Characteristics
DurationANNUAL
Economic Value (Genus)No
Roadless Areas (13)
California (13)
AreaForestAcres
AgnewSequoia National Forest9,561
Deer MountainMendocino National Forest11,716
Devil GulchSierra National Forest30,490
Ferguson RidgeSierra National Forest6,104
Fox MountainLos Padres National Forest52,072
Kings RiverSierra National Forest52,999
Mill CreekSequoia National Forest27,643
MonarchSierra National Forest697
MonoLos Padres National Forest28,141
North MountainStanislaus National Forest7,856
RinconSequoia National Forest54,610
Slate Mtn.Sequoia National Forest12,299
Sycamore SpringsSierra National Forest10,015
References (10)
  1. Barker, W.R., G.L. Nesom, P.M. Beardsley, and N.S. Fraga. 2012. A taxonomic conspectus of Phrymaceae: A narrowed circumscriptions for <i>Mimulus</i>, new and resurrected genera, and new names and combinations. Phytoneuron 39:1-60.
  2. Flora of North America Editorial Committee (FNA). 2019. Flora of North America north of Mexico. Vol. 17: Magnoliophyta: Tetrachondraceae to Orobanchaceae. Oxford Univ. Press, New York. xxiv + 737 pp.
  3. Global Biodiversity Information Facility (GBIF). 2025. Global Biodiversity Information Facility (GBIF) data portal. Online. Available: https://www.gbif.org/ (accessed 2025).
  4. iNaturalist. 2025. Online. Available: https://www.inaturalist.org (accessed 2025).
  5. Jepson Flora Project (eds.) 2025. Jepson eFlora. Online. Available: https://ucjeps.berkeley.edu/eflora/ (accessed 2025).
  6. Munz, P.A., with D.D. Keck. 1959. A California flora. Univ. California Press, Berkeley. 1681 pp.
  7. NatureServe. 2025. NatureServe Network Biodiversity Location Data. NatureServe, Arlington, Virginia.
  8. NatureServe's Rapid Analysis of Rarity and Endangerment Conservation Assessment Tool (RARECAT). 2024. Version: 1.1.1 (released Oct 01, 2024).
  9. Southwest Environmental Information Network (SEINet). 2025. Collections Databases. Online. Available: https://swbiodiversity.org/seinet/collections/index.php (accessed 2025).
  10. Wildflower Center. 2020. Native Plant Database: <i>Mimulus bolanderi</i>. Lady Bird Johnson Wildflower Center, University of Texas, Austin. Accessed: September 21, 2022. https://www.wildflower.org/plants/result.php?id_plant=MIBO3