FNA: Erythranthe microphylla vs. Erythranthe minor

	Erythranthe microphylla	Erythranthe minor
	Bentham's monkeyflower, small-leaf monkey-flower	Colorado monkeyflower
Habit	Annuals, fibrous-rooted.	Perennials, rhizomatous, colonial, rhizomes forming a mass, branching, filiform.
Stems	erect, simple, sometimes many-branched from basal cauline nodes, terete, sometimes distinctly 4-angled, (3–)5–30(–45) cm, glabrous below inflorescence, sometimes distals hirtellous, hairs commonly deflexed, or mixed hirtellous and stipitate-glandular, sometimes only short villous-glandular, hairs gland-tipped.	erect to erect-ascending, branched, 5–20 cm, densely minutely hirtellous and eglandular or with a mixture of hirtellous and gland-tipped hairs.
Leaves	basal and cauline, basal sometimes absent at flowering; petiole: basal or proximals to medials 3–25(–35) mm, distals 0 mm (then blade subclasping to narrowly perfoliate); blade often purplish, palmately 3–5-veined, ovate or ovate-lanceolate to elliptic-ovate, suborbicular, or depressed-ovate, (3–)10–35 × 3–25 mm, base rounded to truncate or subcordate, margins shallowly crenate to sharply crenate-serrate, teeth 5–10 per side, basal and proximal often irregularly incised near petiole and sublyrate, apex acute to obtuse-rounded, surfaces glabrous or sparsely to moderately hirtellous, eglandular.	basal and cauline; petiole 0 mm or proximals 1–3 mm; blade palmately 3-veined, broadly ovate to elliptic-ovate or lanceolate, 8–25 × 5–15 mm, base cuneate to truncate, margins shallowly dentate to denticulate, apex acute to obtuse, surfaces glabrous.
Flowers	herkogamous, 1–8(–14), usually from distal nodes, chasmogamous.	herkogamous, 1–3, from distal nodes.
Styles	sparsely hirtellous.	sparsely hirtellous.
Corollas	yellow to golden yellow or orangish yellow, usually red-spotted, abaxial limb sometimes with a large red splotch, bilaterally symmetric, bilabiate; tube-throat broadly funnelform, (6–)8–16(–20) mm, exserted (1–)2–6(–8) mm beyond calyx margin; limb expanded 8–25 mm, palate villous.	yellow, not red-dotted, bilaterally symmetric, bilabiate; tube-throat tubular-funnelform, 9–11 mm, exserted 0–1(–2) mm beyond calyx margin.
Fruiting pedicels	8–30(–50) mm, distals hirtellous, hairs commonly deflexed, or mixed hirtellous and stipitate-glandular, sometimes only short villous-glandular, hairs gland-tipped.	10–20 mm, densely minutely hirtellous and eglandular or with a mixture of hirtellous and gland-tipped hairs.
Fruiting calyces	nodding 30–90º, sometimes red-tinged or -dotted, ovoid-campanulate to broadly cylindric-campanulate, inflated, sagittally compressed, (7–)9–16(–20) mm, minutely hirtellous, hairs sometimes reduced to basal cells, or glabrous, throat strongly to weakly closing.	nodding 80–100º, not purple-dotted, cylindric-campanulate, inflated, sagittally compressed, 10–13 mm, densely minutely hirtellous and eglandular or with a mixture of hirtellous and gland-tipped hairs, throat closing.
Capsules	included, 6–9(–11) mm.	included, 5–8 mm.
Anthers	included, glabrous.	included, glabrous.
2n	= 28, 56.

	Erythranthe microphylla	Erythranthe minor
Phenology	Flowering Mar–Jul.	Flowering Jul–Aug(–Sep).
Habitat	Rock depressions, rocky ridges, cliff faces, roadcuts, wet meadows, seeps, stream banks, drying ponds, ephemeral stream channels, vernal springs over serpentine, roadsides and roadside ditches, dry banks, lava soils, loam, clay, gravel, yellow pine, oak-pine, mixed oak woodlands, oak-chaparral.	Stream and lake edges, intermittent subalpine water courses, roadside ditches, subalpine to alpine.
Elevation	20–1700(–2600) m. (100–5600(–8500) ft.)	3000–3700 m. (9800–12100 ft.)
Distribution	CA; ID; NV; OR; WA; BC [WildflowerSearch map]	CO; NM
Discussion	Erythranthe microphylla is characterized by its annual duration (fibrous-rooted), usually simple stems, relatively widely spaced leaves, glabrous or hirtellous vestiture, open corollas, and calyces closing at the throat. Even in the smallest corollas, the stigma is positioned above the adaxial anther pair, indicating that all are primarily allogamous. Some plants have basal and proximal cauline leaves with exaggeratedly and irregularly toothed-incised margins (especially in Lake and Napa counties, California, as in the types of Mimulus glareosus and M. guttatus var. insignis, respectively), but a similar tendency can be seen over most of the geographic range. Plants of E. microphylla vary greatly in height, leaf size, and flower size (the larger flowers approaching the size of those in E. grandis and E. decora), yet all seem to be within the expression of a single species. An inversion sequence of chromosome 8 (the DIV1 region) is perfectly correlated with the life history features of at least four species of sect. Simiolus (D. B. Lowry and J. H. Willis 2010). One sequence occurs in Erythranthe guttata and E. grandis, which are perennial and rhizomatous, occur in habitats with year-round moisture, and flower relatively late in the season, while the opposite sequence occurs in E. nasuta and E. microphylla, which are annual and slender-taprooted or fibrous-rooted, occur in quickly drying habitats, and flower in early season. The inversion, with its tightly linked, locally adaptive alleles, contributes to isolating mechanisms between species with contrasting sequences and preserves the constellation of features that makes each a recognizable entity. Hybridization and apparent introgression occur among Erythranthe guttata, E. microphylla, and E. nasuta, yet each remains distinct in duration, perennating morphology, and habit. Erythranthe arvensis (annual) also is a member of this gene-sharing group. A whole-genome analysis by A. D. Twyford and J. Friedman (2015) showed that populations of E. guttata and E. microphylla cluster together within each of several geographically delimited regions; they interpreted their trees as showing phylogenetic relationships and concluded that E. guttata and E. microphylla are conspecific. Other evidence (G. L. Nesom 2014c, 2014d), particularly the DIV1 inversion sequence, indicates that E. guttata and E. grandis are most closely related to each other and were derived from an ancestor of annual duration. Thus, E. microphylla and E. nasuta are morphologically and phylogenetically distinct from E. guttata, despite extensive gene flow where they are sympatric with it. (Discussion copyrighted by Flora of North America; reprinted with permission.)	The corollas of Erythranthe minor are shorter than those of typical E. tilingii, and the two species are allopatric. Corollas of E. tilingii rarely may be equally as short as those of E. minor but are produced in scattered localities on plants that are depauperate in other ways. The range of E. minor is primarily in Colorado apparently extending southward into the Wheeler Peak area of Taos County, New Mexico. Attribution of its range into the La Sal Mountains of east-central Utah has been based on misidentifications of E. guttata; the distinction between E. guttata and E. minor in Colorado also needs clarification. Mimulus luteus Linnaeus var. alpinus A. Gray (1863, the type from Colorado) is an illegitimate name for Erythranthe minor, preceded by M. luteus var. alpinus Lindley (1827). (Discussion copyrighted by Flora of North America; reprinted with permission.)
Source	FNA vol. 17, p. 415.	FNA vol. 17, p. 409.
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. 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. 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. 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
Synonyms	Mimulus microphyllus, M. glareosus, M. guttatus var. depauperatus, M. guttatus var. insignis, M. guttatus var. microphyllus, M. guttatus var. platycalyx, M. langsdorffii var. insignis, M. langsdorffii var. microphyllus, M. luteus var. depauperatus, M. nasutus var. insignis, M. platycalyx	Mimulus minor, M. alpinus, M. langsdorffii var. alpinus, M. langsdorffii var. minor
Name authority	(Bentham) G. L. Nesom: Phytoneuron 2012-39: 44. (2012)	(A. Nelson) G. L. Nesom: Phytoneuron 2012-39: 44. (2012)
Web links	Local floras: BC, CA, OR, WA Local Web sites: CalFlora, CalPhotos, Flora NW, PNW Herbaria WildflowerSearch iNaturalist (observations) LBJ Wildflower Center SEINet Plants of the World Online Encyclopedia of Life Wikipedia Google Image Search	WildflowerSearch iNaturalist (observations) LBJ Wildflower Center SEINet Plants of the World Online Encyclopedia of Life Wikipedia Google Image Search

Erythranthe minor

Bentham's monkeyflower, small-leaf monkey-flower

Colorado monkeyflower

Habit

Annuals, fibrous-rooted.

Perennials, rhizomatous, colonial, rhizomes forming a mass, branching, filiform.

Stems

erect, simple, sometimes many-branched from basal cauline nodes, terete, sometimes distinctly 4-angled, (3–)5–30(–45) cm, glabrous below inflorescence, sometimes distals hirtellous, hairs commonly deflexed, or mixed hirtellous and stipitate-glandular, sometimes only short villous-glandular, hairs gland-tipped.

erect to erect-ascending, branched, 5–20 cm, densely minutely hirtellous and eglandular or with a mixture of hirtellous and gland-tipped hairs.

Leaves

basal and cauline, basal sometimes absent at flowering;

petiole: basal or proximals to medials 3–25(–35) mm, distals 0 mm (then blade subclasping to narrowly perfoliate);

blade often purplish, palmately 3–5-veined, ovate or ovate-lanceolate to elliptic-ovate, suborbicular, or depressed-ovate, (3–)10–35 × 3–25 mm, base rounded to truncate or subcordate, margins shallowly crenate to sharply crenate-serrate, teeth 5–10 per side, basal and proximal often irregularly incised near petiole and sublyrate, apex acute to obtuse-rounded, surfaces glabrous or sparsely to moderately hirtellous, eglandular.

basal and cauline;

petiole 0 mm or proximals 1–3 mm;

blade palmately 3-veined, broadly ovate to elliptic-ovate or lanceolate, 8–25 × 5–15 mm, base cuneate to truncate, margins shallowly dentate to denticulate, apex acute to obtuse, surfaces glabrous.

Flowers

herkogamous, 1–8(–14), usually from distal nodes, chasmogamous.

herkogamous, 1–3, from distal nodes.

Styles

sparsely hirtellous.

Corollas

yellow to golden yellow or orangish yellow, usually red-spotted, abaxial limb sometimes with a large red splotch, bilaterally symmetric, bilabiate;

tube-throat broadly funnelform, (6–)8–16(–20) mm, exserted (1–)2–6(–8) mm beyond calyx margin;

limb expanded 8–25 mm, palate villous.

yellow, not red-dotted, bilaterally symmetric, bilabiate;

tube-throat tubular-funnelform, 9–11 mm, exserted 0–1(–2) mm beyond calyx margin.

Fruiting pedicels

8–30(–50) mm, distals hirtellous, hairs commonly deflexed, or mixed hirtellous and stipitate-glandular, sometimes only short villous-glandular, hairs gland-tipped.

10–20 mm, densely minutely hirtellous and eglandular or with a mixture of hirtellous and gland-tipped hairs.

Fruiting calyces

nodding 30–90º, sometimes red-tinged or -dotted, ovoid-campanulate to broadly cylindric-campanulate, inflated, sagittally compressed, (7–)9–16(–20) mm, minutely hirtellous, hairs sometimes reduced to basal cells, or glabrous, throat strongly to weakly closing.

nodding 80–100º, not purple-dotted, cylindric-campanulate, inflated, sagittally compressed, 10–13 mm, densely minutely hirtellous and eglandular or with a mixture of hirtellous and gland-tipped hairs, throat closing.

Capsules

included, 6–9(–11) mm.

included, 5–8 mm.

Anthers

included, glabrous.

= 28, 56.

Erythranthe microphylla

Erythranthe minor

Phenology

Flowering Mar–Jul.

Flowering Jul–Aug(–Sep).

Habitat

Rock depressions, rocky ridges, cliff faces, roadcuts, wet meadows, seeps, stream banks, drying ponds, ephemeral stream channels, vernal springs over serpentine, roadsides and roadside ditches, dry banks, lava soils, loam, clay, gravel, yellow pine, oak-pine, mixed oak woodlands, oak-chaparral.

Stream and lake edges, intermittent subalpine water courses, roadside ditches, subalpine to alpine.

Elevation

20–1700(–2600) m. (100–5600(–8500) ft.)

3000–3700 m. (9800–12100 ft.)

Distribution

CA; ID; NV; OR; WA; BC

[WildflowerSearch map]

CO; NM

Discussion

Erythranthe microphylla is characterized by its annual duration (fibrous-rooted), usually simple stems, relatively widely spaced leaves, glabrous or hirtellous vestiture, open corollas, and calyces closing at the throat. Even in the smallest corollas, the stigma is positioned above the adaxial anther pair, indicating that all are primarily allogamous. Some plants have basal and proximal cauline leaves with exaggeratedly and irregularly toothed-incised margins (especially in Lake and Napa counties, California, as in the types of Mimulus glareosus and M. guttatus var. insignis, respectively), but a similar tendency can be seen over most of the geographic range. Plants of E. microphylla vary greatly in height, leaf size, and flower size (the larger flowers approaching the size of those in E. grandis and E. decora), yet all seem to be within the expression of a single species.

An inversion sequence of chromosome 8 (the DIV1 region) is perfectly correlated with the life history features of at least four species of sect. Simiolus (D. B. Lowry and J. H. Willis 2010). One sequence occurs in Erythranthe guttata and E. grandis, which are perennial and rhizomatous, occur in habitats with year-round moisture, and flower relatively late in the season, while the opposite sequence occurs in E. nasuta and E. microphylla, which are annual and slender-taprooted or fibrous-rooted, occur in quickly drying habitats, and flower in early season. The inversion, with its tightly linked, locally adaptive alleles, contributes to isolating mechanisms between species with contrasting sequences and preserves the constellation of features that makes each a recognizable entity.

Hybridization and apparent introgression occur among Erythranthe guttata, E. microphylla, and E. nasuta, yet each remains distinct in duration, perennating morphology, and habit. Erythranthe arvensis (annual) also is a member of this gene-sharing group. A whole-genome analysis by A. D. Twyford and J. Friedman (2015) showed that populations of E. guttata and E. microphylla cluster together within each of several geographically delimited regions; they interpreted their trees as showing phylogenetic relationships and concluded that E. guttata and E. microphylla are conspecific. Other evidence (G. L. Nesom 2014c, 2014d), particularly the DIV1 inversion sequence, indicates that E. guttata and E. grandis are most closely related to each other and were derived from an ancestor of annual duration. Thus, E. microphylla and E. nasuta are morphologically and phylogenetically distinct from E. guttata, despite extensive gene flow where they are sympatric with it.

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

The corollas of Erythranthe minor are shorter than those of typical E. tilingii, and the two species are allopatric. Corollas of E. tilingii rarely may be equally as short as those of E. minor but are produced in scattered localities on plants that are depauperate in other ways. The range of E. minor is primarily in Colorado apparently extending southward into the Wheeler Peak area of Taos County, New Mexico. Attribution of its range into the La Sal Mountains of east-central Utah has been based on misidentifications of E. guttata; the distinction between E. guttata and E. minor in Colorado also needs clarification.

Mimulus luteus Linnaeus var. alpinus A. Gray (1863, the type from Colorado) is an illegitimate name for Erythranthe minor, preceded by M. luteus var. alpinus Lindley (1827).

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

Source

FNA vol. 17, p. 415.

FNA vol. 17, p. 409.

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. 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. 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. 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

Synonyms

Mimulus microphyllus, M. glareosus, M. guttatus var. depauperatus, M. guttatus var. insignis, M. guttatus var. microphyllus, M. guttatus var. platycalyx, M. langsdorffii var. insignis, M. langsdorffii var. microphyllus, M. luteus var. depauperatus, M. nasutus var. insignis, M. platycalyx

Mimulus minor, M. alpinus, M. langsdorffii var. alpinus, M. langsdorffii var. minor

Name authority

(Bentham) G. L. Nesom: Phytoneuron 2012-39: 44. (2012)

(A. Nelson) G. L. Nesom: Phytoneuron 2012-39: 44. (2012)

Web links

Local floras: BC, CA, OR, WA
Local Web sites: CalFlora, CalPhotos, Flora NW, PNW Herbaria
WildflowerSearch
iNaturalist (observations)
LBJ Wildflower Center
SEINet
Plants of the World Online
Encyclopedia of Life
Wikipedia
Google Image Search

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

The species comparison tool is brought to you by:

Flora of North America species comparison

Erythranthe microphylla

Erythranthe minor

Erythranthe microphylla

Erythranthe minor