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Erythranthe trinitiensis

Nesom

Trinity Mountains Monkeyflower

G2Imperiled Found in 5 roadless areas NatureServe Explorer →
G2ImperiledGlobal Rank
HighThreat Impact
Identity
Unique IDELEMENT_GLOBAL.2.902406
Element CodePDPHR01070
Record TypeSPECIES
ClassificationSpecies
Classification StatusStandard
Name CategoryVascular Plant
Endemicendemic to a single state or province
KingdomPlantae
PhylumAnthophyta
ClassDicotyledoneae
OrderLamiales
FamilyPhrymaceae
GenusErythranthe
Other Common Names
Pink-margined Monkeyflower (EN)
Concept Reference
Nesom, G.L. 2013. Two new species of Erythranthe sect. Mimulosma (Phrymaceae) from California. Phytoneuron 43:1-10.
Taxonomic Comments
Nesom (2013) explains that Erythranthe trinitiensis has been identified as E. pulsiferae, but it differs in corolla color and in having inflated calyces; the species are closely sympatric in some areas which Nesom interprets as indication of an effective isolating mechanism.
Conservation Status
Rank Method Rank calculation - Biotics v2
Review Date2024-12-18
Change Date2024-12-18
Edition Date2016-03-16
Edition AuthorsR. Bittman (2018) and N. Ventrella (2024)
Threat ImpactHigh
Range Extent5000-20,000 square km (about 2000-8000 square miles)
Number of Occurrences6 - 20
Rank Reasons
Erythranthe trinitiensis is an annual forb which is endemic to peridotite or serpentine soils of northern California, and currently known from four counties in and around Six Rivers, Shasta-Trinity, and Klamath National Forests. There are an estimated 15-19 occurrences of this species, which are threatened by road maintenance, grazing, off-road vehicle activity, recreation, trampling and foot traffic, and altered hydrology. Little is known about trends for Erythranthe trinitiensis, though population numbers likely fluctuate widely year to year in response to precipitation.
Range Extent Comments
Erythranthe trinitiensis occurs in the western United States, where it is endemic to Shasta, Trinity, and Humboldt counties of northern California (Nesom 2013, Serkanic and Sims 2022). Specifically, it occurs mainly in two distinct locations of the Klamath Ranges and North Coast Ranges. A recent (2019) observation also documented this species near Tedoc Mountain in Tehama County (Serkanic and Sims 2022, CalFlora 2024). Range extent was estimated to be 7,238 square kilometers using herbarium specimens, photo-based observations, CalFlora observations, and California Natural Diversity Database data collected between 1993 and 2024 (CalFlora 2024, CCH2 2024, CNDDB 2024, iNaturalist 2024).
Occurrences Comments
By applying a 1 km separation distance to herbarium specimens, photo-based observations, CalFlora observations, and California Natural Diversity Database data documented between 1993 and 2024, there are estimated to be 19 occurrences rangewide (CalFlora 2024, CCH2 2024, CNDDB 2024, iNaturalist 2024). However, the California Native Plant Society estimates that there are 15 occurrences using a smaller separation distance of 1/4 mile (CNPS 2024).
Threat Impact Comments
Many occurrences of Erythranthe trinitiensis occur in moist areas along roadsides and culverts where road maintenance and other disturbances are prevalent (CNPS 2024). Additional threats include grazing (impacting one occurrence), off-road vehicle activity (impacting two occurrences), recreation (impacting one occurrence), trampling and foot traffic (impacting two occurrences), and altered hydrology of unknown cause, though the occurrence is next to a pond so the reason for altered hydrology is assumed to be related to the pond (impacting one occurrence) (CNDDB 2024).
Ecology & Habitat

Habitat

Erythranthe trinitiensis is associated with cismontane woodlands, and upper and lower montane conifer forests (CNPS 2024). It is found in wet meadows, along roadsides, and in seeps over serpentine from 1300 to 2000 m in elevation (Nesom 2013). This species is likely an ultramafic endemic, as the majority plants are found in places where the bedrock geology is mapped as peridotite or serpentine.

Reproduction

Erythranthe trinitiensis flowers from May until July (and sometimes August) (CNPS 2024).
Terrestrial Habitats
Forest - ConiferForest EdgeGrassland/herbaceous
Other Nations (1)
United StatesN2
ProvinceRankNative
CaliforniaS2Yes
Threat Assessments
ThreatScopeSeverityTiming
2 - Agriculture & aquacultureSmall (1-10%)Moderate or 11-30% pop. declineHigh (continuing)
2.3 - Livestock farming & ranchingSmall (1-10%)Moderate or 11-30% pop. declineHigh (continuing)
2.3.4 - Scale unknown/unrecordedSmall (1-10%)Moderate or 11-30% pop. declineHigh (continuing)
4 - Transportation & service corridorsRestricted (11-30%)Serious or 31-70% pop. declineHigh (continuing)
4.1 - Roads & railroadsRestricted (11-30%)Serious or 31-70% pop. declineHigh (continuing)
6 - Human intrusions & disturbanceLarge (31-70%)Serious - moderateHigh (continuing)
6.1 - Recreational activitiesLarge (31-70%)Serious - moderateHigh (continuing)
7 - Natural system modificationsSmall (1-10%)Moderate or 11-30% pop. declineHigh (continuing)
7.2 - Dams & water management/useSmall (1-10%)Moderate or 11-30% pop. declineHigh (continuing)
7.2.11 - Dams (size unknown)Small (1-10%)Moderate or 11-30% pop. declineHigh (continuing)

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Plant Characteristics
DurationANNUAL
Economic Value (Genus)No
Roadless Areas (5)
California (5)
AreaForestAcres
ChinquapinShasta-Trinity National Forest22,040
East ForkShasta-Trinity National Forest6,201
Mt. EddyShasta-Trinity National Forest7,232
Pilot CreekSix Rivers National Forest9,192
UnderwoodShasta-Trinity National Forest3,046
References (9)
  1. CalFlora. 2024. Information on California plants for education, research and conservation. Berkeley, California: The CalFlora Database [web application]. Available: http://www.calflora.org/. (Accessed 2024).
  2. California Native Plant Society (CNPS), Rare Plant Program. 2024. Inventory of Rare and Endangered Plants of California, online edition, v9.5. Online. Available: https://www.rareplants.cnps.org (accessed 2024).
  3. California Natural Diversity Database (CNDDB). 2024. RareFind Version 5.3.0. California Department of Fish and Game, Sacramento.
  4. CCH2 Portal. 2024. Consortium of California Herbaria. Online. Available: https//:www.cch2.org/portal/index.php (Accessed 2024).
  5. Flora of North America Editorial Committee. 1994. Flora of North America north of Mexico. Vol. 3. Oxford Univ. Press, New York and Oxford. Review drafts of portions of manuscripts, 1994-1995.
  6. 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.
  7. iNaturalist. 2024. Online. Available: https://www.inaturalist.org (accessed 2024).
  8. Nesom, G.L. 2013. Two new species of Erythranthe sect. Mimulosma (Phrymaceae) from California. Phytoneuron 43:1-10.
  9. Serkanic, S., and A. Sims. 2022. Jan 31 last update. Plant Species Evaluation Form: <i>Erythranthe trinitiensis</i> Nesom (Pink-Margined Monkeyflower). California Native Plant Society. Online. Available: https://rareplantfiles.cnps.org/scc/ErythrantheTrinitiensisSpProfileSCC20220131.pdf (Accessed 2024).