Taxon Report

Erythranthe trinitiensis Nesom

pink-margined monkeyflower

Print Report

Taxon Summary

Erythranthe trinitiensis, commonly known as pink-margined monkeyflower, is a annual herb in the Phrymaceae that is found only in California. It occurs within Cismontane woodland, Lower montane coniferous forest, Meadows and seeps, and Upper montane coniferous forest, growing at elevations from 400 to 2285 meters. Erythranthe trinitiensis is ranked 1B.3, Plants Rare, Threatened or Endangered in California and Elsewhere; Not very threatened in California.

Classification


Scientific Name:	Erythranthe trinitiensis Nesom
Common Name:	pink-margined monkeyflower
Family:	Phrymaceae
Element Code:	PDPHR01070
USDA Plants Symbol:
Synonyms/Other Names:

Ecology and Life History


Lifeform:	annual herb
Blooming Period: Jun-Jul(Aug)	Jun-Jul(Aug)
Elevation:	400-2285 (1310-7495)
General Habitats:	Cismontane woodland, Lower montane coniferous forest, Meadows and seeps, Upper montane coniferous forest
Microhabitat:	Roadsides (often), Serpentine (often)
Microhabitat Details:

Conservation Status


CA Rare Plant Rank:	1B.3
Global Rank:	G2
State Rank:	S2
State List:	None
Fed List:	None
Other Status:	SB_CalBG/RSABG
CRPR Changes:	added to 1B.3 on 2014-01-03

Occurrence Data from the CNDDB


Total Occurrences:	15
Element Occurrence Ranks:
Excellent (A)	1
Good (B)	3
Fair (C)	0
Poor (D)	0
None (X)	0
Unknown (U)	11

Location


California Endemic: True
California Counties and Islands: Name (Code)
Humboldt (HUM), Shasta (SHA), Siskiyou (SIS), Trinity (TRI)
Quads: Name (Quad Code)
Grouse Mtn. (4012376), Hyampom (4012354), Hyampom Mtn. (4012364), Mount Eddy (4112234), Mumbo Basin (4112225), Pony Buck Peak (4012331), Scott Mountain (4112236), South China Mtn. (4112235), Willow Creek (4012386)

Threat List Data from the CNDDB


Threat List Total:	7
EOs with Threat Listed:	Total EOs	% of EOs
	6	40 %
Road/trail construction/maint.	3	20%
Foot traffic/trampling	2	13%
ORV activity	2	13%
Other	1	6%
Recreational use (non-ORV)	1	6%
Grazing	1	6%
Altered flood/tidal/hydrologic regime	1	6%

Notes



Previously identified as, and similar to, E. pulsiferae. See Phytoneuron 2013-43:1-10 (2013) for original description.
Threats:

Taxonomy:

Selected References

CRPR List Addition on 2014-01-03

Erythranthe trinitiensis profile for potential Species of Conservation Concern evaluation (2022)

Citation California Native Plant Society, Rare Plant Program. 2025. Rare Plant Inventory (online edition, v9.5.1). Website https://www.rareplants.cnps.org [accessed 17 November 2025].