FNA: Erythranthe caespitosa vs. Erythranthe willisii

	Erythranthe caespitosa	Erythranthe willisii
	large mountain monkey-flower, mountain monkeyflower, Olympic monkeyflower, subalpine monkeyflower	Willis' monkeyflower
Habit	Perennials, rhizomatous, rooting at proximal nodes, sometimes producing creeping, small-leaved runners, forming matted colonies, rhizomes filiform.	Perennials, rhizomatous, rarely rooting at proximal nodes, usually forming large colonies, rhizomes white, usually highly branching.
Stems	procumbent or decumbent to decumbent-ascending, delicate, usually in masses, terete or flattish, branched, 3–10 cm, glabrous, minutely hirtellous, or stipitate-glandular.	usually sprawling-decumbent, branched, sometimes simple, 7–45 cm, nodes (2–)4–15+, densely glandular-villous, hairs 1–2 mm, glandular, internodes evident.
Leaves	basal and cauline; petiole: proximals 2–5 mm, distals 0 mm; blade often purple beneath, palmately 3-veined, orbicular to narrowly elliptic or ovate, proximals usually sublyrate, 3–12 mm, becoming larger distally, base cuneate to a short petiole, margins entire, mucronulate, or barely denticulate, apex obtuse, surfaces sparsely to moderately puberulent, hairs minute, stipitate-glandular.	usually cauline, basal not persistent, distinctly separated; petiole 0 mm, sometimes 1–2 mm at proximal nodes; blade bicolored, purplish abaxially, pinnately veined, ovate to elliptic-ovate, midcauline 10–35 × 6–18 mm, base rounded to subcordate, margins coarsely serrate-dentate to denticulate or subentire, apex short-attenuate to acute, obtuse, or rounded, surfaces densely glandular-villous, hairs 1–2 mm, gland-tipped.
Flowers	herkogamous, 1–3, from distal nodes, commonly solitary.	herkogamous, (4–)8–30+, from medial to distal nodes, sometimes from all nodes.
Styles	minutely hirtellous.	glabrous.
Corollas	yellow, dark red-spotted, bilaterally symmetric, bilabiate; tube-throat broadly funnelform to cylindric-funnelform, 15–18 mm, exserted beyond calyx margin; abaxial limb with deflexed-spreading lobes, adaxial with ascending lobes, palate partially closed.	yellow, throat, tube, and proximal portion of abaxial 3 lobes with fine, red to brownish lines, weakly bilaterally or nearly radially symmetric, weakly bilabiate or nearly regular; tube-throat narrowly funnelform, 12–15 mm, exserted beyond calyx margin; limb 9–12 mm wide (pressed), lobes oblong-obovate, apex rounded to notched.
Fruiting pedicels	10–30(–40) mm, sparsely to moderately villous, hairs short, gland-tipped, sometimes hirtellous.	4–20(–25) mm, densely glandular-villous, hairs 1–2 mm, gland-tipped.
Fruiting calyces	broadly campanulate, inflated, sagittally compressed, 7–15 mm, glabrous, minutely hirtellous, or stipitate-glandular, throat closing, proximalmost lobe pair upcurving, distalmost 3–5 mm, prominently protruding.	ridge- to wing-angled, campanulate to cylindric-campanulate, weakly inflated, 7–10 mm, densely glandular-villous, lobes erect to slightly spreading, unequal, triangular to linear-lanceolate, 2–4 mm, apex acuminate-apiculate.
Capsules	included, 4–5 mm.	included, 4–5 mm.
Anthers	included, glabrous.	included, glabrous or finely hirtellous to scabrous.

	Erythranthe caespitosa	Erythranthe willisii
Phenology	Flowering Jul–Sep.	Flowering May–Sep.
Habitat	Alpine meadows and slopes, stream banks, wet rocks in streams, wet crevices, talus.	Seepage, drainage margins, moist soils, talus, cracks and crevices, soils deprived from serpentine.
Elevation	1100–2000(–2300) m. (3600–6600(–7500) ft.)	(500–)700–900 m. ((1600–)2300–3000 ft.)
Distribution	WA; BC [WildflowerSearch map]	CA
Discussion	Erythranthe caespitosa is endemic to northwestern and central Washington (Cascade and Olympic mountains) and adjacent British Columbia (Cascades, Selkirk Mountains and Chilliwack Valley, Coast Mountains). The plants have consistently small leaves with subentire margins, and the stems are consistently procumbent to decumbent-ascending, usually forming matted colonies. Erythranthe caespitosa and E. tilingii appear to be sympatric in counties of northwestern Washington, but this needs to be verified in the field. (Discussion copyrighted by Flora of North America; reprinted with permission.)	Erythranthe willisii is narrowly endemic over serpentine along the North Fork Feather River (including the North Branch) in Plumas County. In the original description, its range was said to include serpentine localities in closely adjacent areas of east-central Butte, Plumas, and northwestern Yuba counties, but subsequent field work has shown that these peripheral populations are E. moschata, and that E. willisii occurs only in the bottom of the Serpentine Canyon area. The most consistent and recognizable features of E. willisii are the long, sprawling stems often spread over a large area, sometimes reaching at least 45 cm and often with many crowded nodes, sessile or subsessile leaves with rounded to subcordate bases, and short pedicels, characteristically no longer than the subtending leaves (except sometimes the distal ones where subtending leaves are distinctly reduced in size). It is possible that stem growth in E. willisii is indeterminate versus determinate in E. moschata. Sessile to subsessile leaves occur in E. moschata, especially in the California Sierra Nevada, but petiole length and leaf base shape are variable within populations; lack of petioles and a rounded/subcordate base are fixed characters in E. willisii (as they are also in E. ptilota). Although large colonies of E. moschata are sometimes encountered, the individual plants tend to be erect (in California) and with few distal flowers. In the field, the dense vestiture of E. willisii is a prominent feature, but this is harder to distinguish in pressed specimens, and there is a strong tendency for purple abaxial leaf coloration in E. willisii. Phenology and flower morphology of E. willisii and E. moschata appear to be similar, but E. moschata in north-central California does not occur at as low elevations as E. willisii. (Discussion copyrighted by Flora of North America; reprinted with permission.)
Source	FNA vol. 17, p. 409.	FNA vol. 17, p. 401.
Parent taxa	Phrymaceae > Erythranthe	Phrymaceae > Erythranthe
Sibling taxa	E. acutidens, E. alsinoides, E. ampliata, E. androsacea, E. arenaria, E. arenicola, E. arvensis, E. barbata, E. bicolor, E. brachystylis, E. breviflora, E. breweri, E. calcicola, E. calciphila, E. cardinalis, E. carsonensis, E. charlestonensis, E. chinatiensis, E. cinnabarina, E. corallina, E. cordata, E. decora, E. dentata, E. diffusa, E. discolor, E. eastwoodiae, E. erubescens, E. exigua, E. filicaulis, E. filicifolia, E. floribunda, E. gemmipara, E. geniculata, E. geyeri, E. glaucescens, E. gracilipes, E. grandis, E. grayi, E. guttata, E. hallii, E. hardhamiae, E. hymenophylla, E. inamoena, E. inconspicua, E. inflatula, E. jungermannioides, E. laciniata, E. latidens, E. lewisii, E. linearifolia, E. marmorata, E. michiganensis, E. microphylla, E. minor, E. montioides, E. moschata, E. nasuta, E. norrisii, E. nudata, E. palmeri, E. pardalis, E. parishii, E. parvula, E. patula, E. percaulis, E. primuloides, E. ptilota, E. pulsiferae, E. purpurea, E. regni, E. rhodopetra, E. rubella, E. scouleri, E. shevockii, E. sierrae, E. suksdorfii, E. taylorii, E. thermalis, E. tilingii, E. trinitiensis, E. unimaculata, E. utahensis, E. verbenacea, E. washingtonensis, E. willisii	E. acutidens, E. alsinoides, E. ampliata, E. androsacea, E. arenaria, E. arenicola, E. arvensis, E. barbata, E. bicolor, E. brachystylis, E. breviflora, E. breweri, E. caespitosa, E. calcicola, E. calciphila, E. cardinalis, E. carsonensis, E. charlestonensis, E. chinatiensis, E. cinnabarina, E. corallina, E. cordata, E. decora, E. dentata, E. diffusa, E. discolor, E. eastwoodiae, E. erubescens, E. exigua, E. filicaulis, E. filicifolia, E. floribunda, E. gemmipara, E. geniculata, E. geyeri, E. glaucescens, E. gracilipes, E. grandis, E. grayi, E. guttata, E. hallii, E. hardhamiae, E. hymenophylla, E. inamoena, E. inconspicua, E. inflatula, E. jungermannioides, E. laciniata, E. latidens, E. lewisii, E. linearifolia, E. marmorata, E. michiganensis, E. microphylla, E. minor, E. montioides, E. moschata, E. nasuta, E. norrisii, E. nudata, E. palmeri, E. pardalis, E. parishii, E. parvula, E. patula, E. percaulis, E. primuloides, E. ptilota, E. pulsiferae, E. purpurea, E. regni, E. rhodopetra, E. rubella, E. scouleri, E. shevockii, E. sierrae, E. suksdorfii, E. taylorii, E. thermalis, E. tilingii, E. trinitiensis, E. unimaculata, E. utahensis, E. verbenacea, E. washingtonensis
Synonyms	Mimulus scouleri var. caespitosus, M. caespitosus, M. tilingii var. caespitosus
Name authority	(Greene) G. L. Nesom: Phytoneuron 2012-39: 43. (2012)	G. L. Nesom: Phytoneuron 2017-17: 7, figs. 14–22. (2017)
Web links	Local floras: BC, OR, WA Local Web sites: Flora NW, PNW Herbaria WildflowerSearch iNaturalist (observations) LBJ Wildflower Center SEINet Plants of the World Online Encyclopedia of Life Wikipedia Google Image Search	Local Web sites: CalFlora, CalPhotos WildflowerSearch iNaturalist (observations) LBJ Wildflower Center SEINet Plants of the World Online Encyclopedia of Life Wikipedia Google Image Search

Erythranthe willisii

large mountain monkey-flower, mountain monkeyflower, Olympic monkeyflower, subalpine monkeyflower

Willis' monkeyflower

Habit

Perennials, rhizomatous, rooting at proximal nodes, sometimes producing creeping, small-leaved runners, forming matted colonies, rhizomes filiform.

Perennials, rhizomatous, rarely rooting at proximal nodes, usually forming large colonies, rhizomes white, usually highly branching.

Stems

procumbent or decumbent to decumbent-ascending, delicate, usually in masses, terete or flattish, branched, 3–10 cm, glabrous, minutely hirtellous, or stipitate-glandular.

usually sprawling-decumbent, branched, sometimes simple, 7–45 cm, nodes (2–)4–15+, densely glandular-villous, hairs 1–2 mm, glandular, internodes evident.

Leaves

basal and cauline;

petiole: proximals 2–5 mm, distals 0 mm;

blade often purple beneath, palmately 3-veined, orbicular to narrowly elliptic or ovate, proximals usually sublyrate, 3–12 mm, becoming larger distally, base cuneate to a short petiole, margins entire, mucronulate, or barely denticulate, apex obtuse, surfaces sparsely to moderately puberulent, hairs minute, stipitate-glandular.

usually cauline, basal not persistent, distinctly separated;

petiole 0 mm, sometimes 1–2 mm at proximal nodes;

blade bicolored, purplish abaxially, pinnately veined, ovate to elliptic-ovate, midcauline 10–35 × 6–18 mm, base rounded to subcordate, margins coarsely serrate-dentate to denticulate or subentire, apex short-attenuate to acute, obtuse, or rounded, surfaces densely glandular-villous, hairs 1–2 mm, gland-tipped.

Flowers

herkogamous, 1–3, from distal nodes, commonly solitary.

herkogamous, (4–)8–30+, from medial to distal nodes, sometimes from all nodes.

Styles

minutely hirtellous.

glabrous.

Corollas

yellow, dark red-spotted, bilaterally symmetric, bilabiate;

tube-throat broadly funnelform to cylindric-funnelform, 15–18 mm, exserted beyond calyx margin;

abaxial limb with deflexed-spreading lobes, adaxial with ascending lobes, palate partially closed.

yellow, throat, tube, and proximal portion of abaxial 3 lobes with fine, red to brownish lines, weakly bilaterally or nearly radially symmetric, weakly bilabiate or nearly regular;

tube-throat narrowly funnelform, 12–15 mm, exserted beyond calyx margin;

limb 9–12 mm wide (pressed), lobes oblong-obovate, apex rounded to notched.

Fruiting pedicels

10–30(–40) mm, sparsely to moderately villous, hairs short, gland-tipped, sometimes hirtellous.

4–20(–25) mm, densely glandular-villous, hairs 1–2 mm, gland-tipped.

Fruiting calyces

broadly campanulate, inflated, sagittally compressed, 7–15 mm, glabrous, minutely hirtellous, or stipitate-glandular, throat closing, proximalmost lobe pair upcurving, distalmost 3–5 mm, prominently protruding.

ridge- to wing-angled, campanulate to cylindric-campanulate, weakly inflated, 7–10 mm, densely glandular-villous, lobes erect to slightly spreading, unequal, triangular to linear-lanceolate, 2–4 mm, apex acuminate-apiculate.

Capsules

included, 4–5 mm.

Anthers

included, glabrous.

included, glabrous or finely hirtellous to scabrous.

Erythranthe caespitosa

Erythranthe willisii

Phenology

Flowering Jul–Sep.

Flowering May–Sep.

Habitat

Alpine meadows and slopes, stream banks, wet rocks in streams, wet crevices, talus.

Seepage, drainage margins, moist soils, talus, cracks and crevices, soils deprived from serpentine.

Elevation

1100–2000(–2300) m. (3600–6600(–7500) ft.)

(500–)700–900 m. ((1600–)2300–3000 ft.)

Distribution

WA; BC

[WildflowerSearch map]

Discussion

Erythranthe caespitosa is endemic to northwestern and central Washington (Cascade and Olympic mountains) and adjacent British Columbia (Cascades, Selkirk Mountains and Chilliwack Valley, Coast Mountains). The plants have consistently small leaves with subentire margins, and the stems are consistently procumbent to decumbent-ascending, usually forming matted colonies. Erythranthe caespitosa and E. tilingii appear to be sympatric in counties of northwestern Washington, but this needs to be verified in the field.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Erythranthe willisii is narrowly endemic over serpentine along the North Fork Feather River (including the North Branch) in Plumas County. In the original description, its range was said to include serpentine localities in closely adjacent areas of east-central Butte, Plumas, and northwestern Yuba counties, but subsequent field work has shown that these peripheral populations are E. moschata, and that E. willisii occurs only in the bottom of the Serpentine Canyon area. The most consistent and recognizable features of E. willisii are the long, sprawling stems often spread over a large area, sometimes reaching at least 45 cm and often with many crowded nodes, sessile or subsessile leaves with rounded to subcordate bases, and short pedicels, characteristically no longer than the subtending leaves (except sometimes the distal ones where subtending leaves are distinctly reduced in size). It is possible that stem growth in E. willisii is indeterminate versus determinate in E. moschata. Sessile to subsessile leaves occur in E. moschata, especially in the California Sierra Nevada, but petiole length and leaf base shape are variable within populations; lack of petioles and a rounded/subcordate base are fixed characters in E. willisii (as they are also in E. ptilota). Although large colonies of E. moschata are sometimes encountered, the individual plants tend to be erect (in California) and with few distal flowers. In the field, the dense vestiture of E. willisii is a prominent feature, but this is harder to distinguish in pressed specimens, and there is a strong tendency for purple abaxial leaf coloration in E. willisii. Phenology and flower morphology of E. willisii and E. moschata appear to be similar, but E. moschata in north-central California does not occur at as low elevations as E. willisii.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source

FNA vol. 17, p. 409.

FNA vol. 17, p. 401.

Parent taxa

Phrymaceae > Erythranthe

Sibling taxa

E. acutidens, E. alsinoides, E. ampliata, E. androsacea, E. arenaria, E. arenicola, E. arvensis, E. barbata, E. bicolor, E. brachystylis, E. breviflora, E. breweri, E. calcicola, E. calciphila, E. cardinalis, E. carsonensis, E. charlestonensis, E. chinatiensis, E. cinnabarina, E. corallina, E. cordata, E. decora, E. dentata, E. diffusa, E. discolor, E. eastwoodiae, E. erubescens, E. exigua, E. filicaulis, E. filicifolia, E. floribunda, E. gemmipara, E. geniculata, E. geyeri, E. glaucescens, E. gracilipes, E. grandis, E. grayi, E. guttata, E. hallii, E. hardhamiae, E. hymenophylla, E. inamoena, E. inconspicua, E. inflatula, E. jungermannioides, E. laciniata, E. latidens, E. lewisii, E. linearifolia, E. marmorata, E. michiganensis, E. microphylla, E. minor, E. montioides, E. moschata, E. nasuta, E. norrisii, E. nudata, E. palmeri, E. pardalis, E. parishii, E. parvula, E. patula, E. percaulis, E. primuloides, E. ptilota, E. pulsiferae, E. purpurea, E. regni, E. rhodopetra, E. rubella, E. scouleri, E. shevockii, E. sierrae, E. suksdorfii, E. taylorii, E. thermalis, E. tilingii, E. trinitiensis, E. unimaculata, E. utahensis, E. verbenacea, E. washingtonensis, E. willisii

E. acutidens, E. alsinoides, E. ampliata, E. androsacea, E. arenaria, E. arenicola, E. arvensis, E. barbata, E. bicolor, E. brachystylis, E. breviflora, E. breweri, E. caespitosa, E. calcicola, E. calciphila, E. cardinalis, E. carsonensis, E. charlestonensis, E. chinatiensis, E. cinnabarina, E. corallina, E. cordata, E. decora, E. dentata, E. diffusa, E. discolor, E. eastwoodiae, E. erubescens, E. exigua, E. filicaulis, E. filicifolia, E. floribunda, E. gemmipara, E. geniculata, E. geyeri, E. glaucescens, E. gracilipes, E. grandis, E. grayi, E. guttata, E. hallii, E. hardhamiae, E. hymenophylla, E. inamoena, E. inconspicua, E. inflatula, E. jungermannioides, E. laciniata, E. latidens, E. lewisii, E. linearifolia, E. marmorata, E. michiganensis, E. microphylla, E. minor, E. montioides, E. moschata, E. nasuta, E. norrisii, E. nudata, E. palmeri, E. pardalis, E. parishii, E. parvula, E. patula, E. percaulis, E. primuloides, E. ptilota, E. pulsiferae, E. purpurea, E. regni, E. rhodopetra, E. rubella, E. scouleri, E. shevockii, E. sierrae, E. suksdorfii, E. taylorii, E. thermalis, E. tilingii, E. trinitiensis, E. unimaculata, E. utahensis, E. verbenacea, E. washingtonensis

Synonyms

Mimulus scouleri var. caespitosus, M. caespitosus, M. tilingii var. caespitosus

Name authority

(Greene) G. L. Nesom: Phytoneuron 2012-39: 43. (2012)

G. L. Nesom: Phytoneuron 2017-17: 7, figs. 14–22. (2017)

Web links

Unless otherwise noted, all data comes from the online version of the Flora of North America, who have made most of their content available via a Creative Commons license (CC BY 4.0).

Choose a data source: Flora of North America, OregonFlora, UW Burke Herbarium

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Erythranthe caespitosa

Erythranthe willisii

Erythranthe caespitosa

Erythranthe willisii