Taxon Report

Erythranthe diffusa (A.L. Grant) N.S. Fraga

Palomar monkeyflower

Print Report


Ron Vanderhoff, 2019

Taxon Summary

Erythranthe diffusa, commonly known as Palomar monkeyflower, is a annual herb in the Phrymaceae that is found in California and elsewhere. It occurs within Chaparral, and Lower montane coniferous forest, growing at elevations from 1220 to 1830 meters. Erythranthe diffusa is ranked 4.3, Plants of Limited Distribution, A Watch List; Not very threatened in California.

  Classification
Scientific Name:
 Erythranthe diffusa (A.L. Grant) N.S. Fraga
Common Name:
 Palomar monkeyflower
Family: Phrymaceae
Element Code: PDSCR1B0Z0
USDA Plants Symbol:
Synonyms/Other Names:
  • Mimulus diffusus

Ecology and Life History
Lifeform: annual herb
Blooming Period: Apr-Jun Apr-Jun
Elevation: 1220-1830 (4005-6005)
General Habitats: Chaparral, Lower montane coniferous forest
Microhabitat: Gravelly (sometimes), Sandy (sometimes)
Microhabitat Details:

Conservation Status
CA Rare Plant Rank: 4.3
Global Rank: G4
State Rank:
 S3
State List: None
Fed List: None
Other Status: SB_CalBG/RSABG
CRPR Changes:

Occurrence Data from the CNDDB
Total Occurrences: 0
Element Occurrence Ranks:
   Excellent (A) 0
   Good (B) 0
   Fair (C) 0
   Poor (D) 0
   None (X) 0
   Unknown (U) 0

Location
California Endemic:  False
California Counties and Islands: Name (Code)
Los Angeles (LAX), Orange (ORA), Riverside (RIV), San Diego (SDG), Santa Clara (SCL)
Quads: Name (Quad Code)
Alberhill (3311764), Bachelor Mtn. (3311751), Beauty Mountain (3311646), Blackburn Canyon (3311667), Boucher Hill (3311638), Butterfly Peak (3311655), Campo (3211654), Chilao Flat (3411831), Corona South (3311775), Cuyamaca Peak (3211685), Descanso (3211675), Encinitas (3311713), Gilroy (3712115), Hemet (3311668), Hot Springs Mtn. (3311635), Idyllwild (3311666), Jacumba (3211662), Jamul Mountains (3211668), Lake Fulmor (3311677), Live Oak Springs (3211663), Margarita Peak (3311744), Monument Peak (3211684), Morena Reservoir (3211665), Murrieta (3311752), National City (3211761), Palm View Peak (3311665), Palomar Observatory (3311637), Pechanga (3311741), Potrero (3211655), Rancho Mirage (3311664), Rodriquez Mtn. (3311628), Sage (3311658), San Clemente (3311745), San Jacinto Peak (3311676), San Vicente Reservoir (3211688), Santa Ysabel (3311616), Santiago Peak (3311765), Sitton Peak (3311754), Tecate (3211656), Tule Springs (3211686), Vail Lake (3311648), Valley Center (3311721), Viejas Mountain (3211676), Warner Springs (3311636), Wildomar (3311753)

Threat List Data from the CNDDB

Threat List Total: 0
EOs with Threat Listed: Total EOs % of EOs
0 0 %

Notes
Threatened by recreational activities and development. See Annals of the Missouri Botanical Garden 11(2-3):254 (1925) for original description, Phytoneuron 2012-39:1-60 (2012) for revised nomenclature, and Aliso 30(1):49-68 (2012) for taxonomic treatment.
Threats:
Taxonomy:

Selected References

Citation California Native Plant Society, Rare Plant Program. 2025. Rare Plant Inventory (online edition, v9.5.1). Website https://www.rareplants.cnps.org [accessed 10 April 2025].