Mimulus guttatus DC.
yellow monkey-flower (seep monkeyflower)
(Previously in Scrophulariaceae)

Introduction to Vascular Plants


© Gary Lewis     (Photo ID #5290)


E-Flora BC Static Map

Distribution of Mimulus guttatus
Click here to view the full interactive map and legend

Species Information

Annual herb from fibrous roots or a perennial from a creeping stolon, rarely from a rhizome; stems stout and erect or sometimes weak and trailing and rooting at the nodes, 5-80 cm tall, simple or branched, smooth or sparsely hairy above.
Opposite, broadly oval to egg-shaped, 1-10 cm long, coarsely and irregularly toothed, palmately 3- to 7-veined from the base, smooth to thinly hairy, the lower leaves stalked, the upper leaves becoming unstalked, clasping-based, reduced in the inflorescence.
Inflorescence a loose, terminal raceme of several to many, or sometimes 1 to few, long-stalked flowers in the axils of the upper leaves, the stalks 1-4 cm long; corollas tubular, broadly funnel-shaped, yellow with maroon markings in the flaring throat, 1-3 (4 ) cm long, strongly 2-lipped, the lips spreading, the upper lip 2-lobed, the lower 3-lobed, densely yellow-hairy at the throat; calyces bell-shaped, green dotted or tinged with red, smooth or minutely hairy, 6-17 mm long in flower, to 20 mm and asymmetrically swollen in fruit, 5-toothed, the upper tooth larger than the others; stamens 4.
Capsules, broadly oblong, rounded at the tip, narrowed to a short-stalked base, 7-12 mm long; seeds numerous, 0.4-0.5 mm long.
The ssp. haidensis has been recognized in the Queen Charlotte Islands, but it may not be much different from some of the numerous other forms previously named in this complex (see Hitchcock et al. 1959).

SourceThe Illustrated Flora of British Columbia


If more than one illustration is available for a species (e.g., separate illustrations were provided for two subspecies) then links to the separate images will be provided below. Note that individual subspecies or varietal illustrations are not always available.

USDA Species Characteristics

Flower Colour:
Blooming Period:
Mid Spring
Fruit/Seed characteristics:
Colour: Brown
Present over the Summer
Source:  The USDA


Ecological Framework for Mimulus guttatus

The table below shows the species-specific information calculated from
original data (BEC database) provided by the BC Ministry of Forests and Range.
(Updated August, 2013)

Site Information
Value / Class




Elevation (metres)
733 0 2125
Slope Gradient (%)
18 0 150

Aspect (degrees)
[0 - N; 90 - E; 180 - S; 270 - W]

185 5 359
Soil Moisture Regime (SMR)
[0 - very xeric; 4 - mesic;
8 - hydric]
5 0 8
Modal Nutrient Regime
# of field plots
 species was recorded in:
Modal BEC Zone Class

All BEC Zones (# of stations/zone) species was recorded in

At(1), BAFA(1), BWBS(2), CDF(1), CWH(21), ESSF(2), ICH(12), IDF(2), MH(8), MS(3), PP(1), SBPS(6), SBS(14)

Habitat and Range

Wet open sites, including seepage areas, meadows, waterfall spray zones, streambanks, springs, gravel bars, rock ledges and crevices, ditches and clearings in the lowland, steppe, montane and subalpine zones; common throughout BC; N to AK and S YT, E to SK, disjunct to NB and NFand S to PA, MI, NE, NM, AZ, CA and MX.

SourceThe Illustrated Flora of British Columbia


Synonyms and Alternate Names:
Mimulus arvensis Greene
Mimulus bakeri Gandog.
Mimulus brachystylis Edwin
Mimulus clementinus Greene
Mimulus cordatus Greene
Mimulus cuspidata Greene
Mimulus decorus (A.L. Grant) Suksd.
Mimulus equinnus Greene
Mimulus glabratus var. ascendens A. Gray
Mimulus glareosus Greene
Mimulus grandiflorus J.T. Howell
Mimulus grandis (Greene) A. Heller
Mimulus guttatus subsp. arenicola Pennell
Mimulus guttatus subsp. arvensis (Greene) Munz
Mimulus guttatus subsp. guttatus
Mimulus guttatus subsp. haidensis Calder & Roy L. Taylor
Mimulus guttatus subsp. litoralis Pennell
Mimulus guttatus subsp. micranthus (A. Heller) Munz
Mimulus guttatus subsp. scouleri (Hook.) Pennell
Mimulus guttatus var. arvensis (Greene) A.L. Grant
Mimulus guttatus var. decorus A.L. Grant
Mimulus guttatus var. depauperatus (A. Gray) A.L. Grant
Mimulus guttatus var. gracilis (A. Gray) G.R. Campb.
Mimulus guttatus var. grandis Greene
Mimulus guttatus var. hallii (Greene) A.L. Grant
Mimulus guttatus var. insignis Greene
Mimulus guttatus var. laxus (Pennell ex M. Peck) M. Peck
Mimulus guttatus var. lyratus (Benth.) Pennell ex M. Peck
Mimulus guttatus var. microphyllus (Benth.) Pennell ex M. Peck
Mimulus guttatus var. nasutus (Greene) Jeps.
Mimulus guttatus var. puberulus (Greene ex Rydb.) A.L. Grant
Mimulus hallii Greene
Mimulus hirsutus J.T. Howell
Mimulus langsdorffii Donn ex Greene
Mimulus langsdorffii var. argutus Greene
Mimulus langsdorffii var. arvensis (Greene) Jeps.
Mimulus langsdorffii var. californicus Jeps.
Mimulus langsdorffii var. grandis (Greene) Greene
Mimulus langsdorffii var. guttatus (DC.) Jeps.
Mimulus langsdorffii var. insignis (Greene) A.L. Grant
Mimulus langsdorffii var. microphyllus (Benth.) A. Nelson & J.F. Macbr.
Mimulus langsdorffii var. minimus Henry
Mimulus langsdorffii var. nasutus (Greene) Jeps.
Mimulus langsdorffii var. platyphyllus Greene
Mimulus langsdorfii Donn ex Greene
Mimulus langsdorfii var. argutus Greene
Mimulus langsdorfii var. arvensis (Greene) Jepson
Mimulus langsdorfii var. californicus Jepson
Mimulus langsdorfii var. grandis (Greene) Greene
Mimulus langsdorfii var. guttatus (Fisch. ex DC.) Jepson
Mimulus langsdorfii var. insignis (Greene) A.L. Grant
Mimulus langsdorfii var. microphyllus (Benth.) A. Nels. & J.F. Macbr.
Mimulus langsdorfii var. minimus Henry
Mimulus langsdorfii var. nasutus (Greene) Jepson
Mimulus langsdorfii var. platyphyllus Greene
Mimulus laxus Pennell ex M. Peck
Mimulus longulus Greene
Mimulus luteus var. depauperatus A. Gray
Mimulus luteus var. gracilis A. Gray
Mimulus lyratus Benth.
Mimulus maguirei Pennell
Mimulus marmoratus Greene
Mimulus micranthus A. Heller
Mimulus nasutus Greene
Mimulus nasutus var. micranthus (A. Heller) A.L. Grant
Mimulus paniculatus Greene
Mimulus pardalis Pennell
Mimulus parishii Greene
Mimulus petiolaris Greene
Mimulus prionophyllus Greene
Mimulus procerus Greene
Mimulus puberulus Greene ex Rydb.
Mimulus puncticalyx Gandog.
Mimulus rivularis Nutt.
Mimulus scouleri Hook.
Mimulus subreniformis Greene
Mimulus tenellus Nutt. ex A. Gray
Mimulus thermalis A. Nelson
Mimulus unimaculatus Pennell

Taxonomic Notes


Yellow monkey-flower exhibits a leaf-spot polymorphism similar to that in blue-eyed Mary (Collinsia parviflora) and clover ((Trifolium willdenowii). The spots, however, are usually more brownish in colour and usually cover the basal parts of the leaf, although pattern is variable. Frequently the large brown area at the base of the leaf makes the leaf appear to be dying. The spot is caused by anthocyanin pigments in the upper epidermis, and, like gene-expression in blue-eyed Mary, the expression of the gene is controlled by temperature.

The distribution of phenotype frequencies parallels that in blue-eyed Mary and clover on the Flat Top Islands, but the gene for spots is perhaps more widespread in monkey-flower, as we have seen populations polymorphic for spotted leaves as far south as Kern County, California.

Like spotting in other species, spotting in monkey-flower is controlled by a single gene, with the allele for spots dominant. We have found that the variation found in this kind of leaf-spotting is due to modifier genes separate from the leaf-spot gene itself.

Source: Griffiths and Ganders. 1983. Wildflower Genetics: A Field Guide for British Columbia and the Pacific Northwest.


A charming BC native monkey flower with large very showy bright yellow flowers with red spots that are offered in masses in spring. Deserves to be grown in more gardens. Loves moist to average soils.

Note Author: Gary Lewis, Phoenix Perennials


Griffiths, Anthony J. F. and Fred R. Ganders. 1983. Wildflower Genetics: A Field Guide for British Columbia and the Pacific Northwest. Flight Press, Vancouver.