FNA: Erythranthe exigua vs. Erythranthe thermalis

	Erythranthe exigua	Erythranthe thermalis
	eye strain monkeyflower, San Bernardino Mountains monkeyflower	Yellowstone monkeyflower
Habit	Annuals, taprooted.	Annuals, taprooted, rarely with a basal, runnerlike stem.
Stems	erect, simple, sometimes branched near base, 2–10 cm, minutely stipitate-glandular.	erect, simple or branched from basal nodes, 1.5–10(–15) cm, villous-glandular proximally, moderately to densely stipitate-glandular, sometimes hirtellous and eglandular distally.
Leaves	cauline; petiole 0 mm; blade 1-veined, obovate-oblong to narrowly elliptic, ovate, or narrowly ovate, 3–6 mm, base rounded to truncate or cuneate, margins entire or shallowly dentate, apex rounded, surfaces minutely stipitate-glandular.	basal and cauline, cauline 2–5 pairs; petiole: basal and proximal cauline 3–20 mm, distals 0 mm; blade palmately 3–5-veined, suborbicular to ovate, depressed-ovate, ovate-deltate, or reniform, 4–15(–20) × 4–20 mm, base cuneate to truncate or subcordate, margins evenly crenate-dentate to subentire, apex acute to obtuse or rounded, surfaces moderately to densely stipitate-glandular, sometimes hirtellous and eglandular.
Flowers	plesiogamous, (1 or)2–6, from distal or medial to distal nodes.	plesiogamous, 1–5(–9), usually at distal nodes, chasmogamous.
Styles	glabrous.	hirtellous.
Corollas	light lavender to purple, abaxial lobe and palate ridges with yellow patches, bilaterally symmetric, ± bilabiate; tube-throat narrowly funnelform-cylindric, 1.5–2.5 mm, exserted 0.5 mm beyond calyx margin; lobes spreading.	yellow, red-dotted or not, bilaterally symmetric, strongly bilabiate; tube-throat funnelform, 8–12 mm, exserted 1–2 mm beyond calyx margin; limb expanded 12–15 mm, throat open, palate villous.
Fruiting pedicels	divergent-spreading, 15–20 mm, minutely stipitate-glandular.	7–12 mm, moderately to densely stipitate-glandular, sometimes hirtellous and eglandular.
Fruiting calyces	campanulate, 2–2.5 mm, minutely stipitate-glandular.	ovate-campanulate, inflated, sagittally compressed, 8–11 mm, moderately to densely stipitate-glandular, sometimes hirtellous and eglandular, throat closing, adaxial lobe longer than others.
Capsules	distinctly exserted, 3–4 mm.	included, 5–6 mm.
Stigmas	persistent in fruit.
Anthers	included, glabrous.	included, glabrous.
2n		= 28.

	Erythranthe exigua	Erythranthe thermalis
Phenology	Flowering Jun–Jul.	Flowering Mar–Aug.
Habitat	Gentle slopes, along small streams, vernal creeks, pebble plains, openings in Jeffrey pine-juniper forests, runoff areas, vernal depressions, roadsides.	Hot, shallow, quick-drying soils around thermal pools and vents.
Elevation	1800–2400(–2600) m. (5900–7900(–8500) ft.)	2200–2600 m. (7200–8500 ft.)
Distribution	CA; Mexico (Baja California) [WildflowerSearch map]	WY
Discussion	Plants of Erythranthe exigua are diminutive annuals with few nodes and greatly reduced leaves, corollas, and calyces, wide spreading pedicels, and lavender flowers with small but bilabiate limbs. The species is known only from the San Bernardino Mountains of San Bernardino County and in adjacent Mexico. (Discussion copyrighted by Flora of North America; reprinted with permission.)	Erythranthe thermalis is endemic to Yellowstone National Park in northwestern Wyoming. The species is recognized by its annual duration (without rhizomes), reduced stature and leaf size, and short, but broad-limbed, corollas with autogamous fertilization. Typical E. guttata (rhizomatous, herkogamous) also grows in the immediately surrounding areas but apparently not in hot soils. Each species maintains distinctions in growth form, phenology and mating system in common garden experiments (Y. Lekberg et al. 2012). (Discussion copyrighted by Flora of North America; reprinted with permission.)
Source	FNA vol. 17, p. 406.	FNA vol. 17, p. 413.
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. 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. tilingii, E. trinitiensis, E. unimaculata, E. utahensis, E. verbenacea, E. washingtonensis, E. willisii
Synonyms	Mimulus exiguus	Mimulus thermalis
Name authority	(A. Gray) G. L. Nesom & N. S. Fraga: Phytoneuron 2012-39: 42. (2012)	(A. Nelson) G. L. Nesom: Phytoneuron 2012-39: 44. (2012)
Web links	Local floras: CA Local Web sites: CalFlora, CalPhotos 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 thermalis

eye strain monkeyflower, San Bernardino Mountains monkeyflower

Yellowstone monkeyflower

Habit

Annuals, taprooted.

Annuals, taprooted, rarely with a basal, runnerlike stem.

Stems

erect, simple, sometimes branched near base, 2–10 cm, minutely stipitate-glandular.

erect, simple or branched from basal nodes, 1.5–10(–15) cm, villous-glandular proximally, moderately to densely stipitate-glandular, sometimes hirtellous and eglandular distally.

Leaves

cauline;

petiole 0 mm;

blade 1-veined, obovate-oblong to narrowly elliptic, ovate, or narrowly ovate, 3–6 mm, base rounded to truncate or cuneate, margins entire or shallowly dentate, apex rounded, surfaces minutely stipitate-glandular.

basal and cauline, cauline 2–5 pairs;

petiole: basal and proximal cauline 3–20 mm, distals 0 mm;

blade palmately 3–5-veined, suborbicular to ovate, depressed-ovate, ovate-deltate, or reniform, 4–15(–20) × 4–20 mm, base cuneate to truncate or subcordate, margins evenly crenate-dentate to subentire, apex acute to obtuse or rounded, surfaces moderately to densely stipitate-glandular, sometimes hirtellous and eglandular.

Flowers

plesiogamous, (1 or)2–6, from distal or medial to distal nodes.

plesiogamous, 1–5(–9), usually at distal nodes, chasmogamous.

Styles

glabrous.

hirtellous.

Corollas

light lavender to purple, abaxial lobe and palate ridges with yellow patches, bilaterally symmetric, ± bilabiate;

tube-throat narrowly funnelform-cylindric, 1.5–2.5 mm, exserted 0.5 mm beyond calyx margin;

lobes spreading.

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

tube-throat funnelform, 8–12 mm, exserted 1–2 mm beyond calyx margin;

limb expanded 12–15 mm, throat open, palate villous.

Fruiting pedicels

divergent-spreading, 15–20 mm, minutely stipitate-glandular.

7–12 mm, moderately to densely stipitate-glandular, sometimes hirtellous and eglandular.

Fruiting calyces

campanulate, 2–2.5 mm, minutely stipitate-glandular.

ovate-campanulate, inflated, sagittally compressed, 8–11 mm, moderately to densely stipitate-glandular, sometimes hirtellous and eglandular, throat closing, adaxial lobe longer than others.

Capsules

distinctly exserted, 3–4 mm.

included, 5–6 mm.

Stigmas

persistent in fruit.

Anthers

included, glabrous.

= 28.

Erythranthe exigua

Erythranthe thermalis

Phenology

Flowering Jun–Jul.

Flowering Mar–Aug.

Habitat

Gentle slopes, along small streams, vernal creeks, pebble plains, openings in Jeffrey pine-juniper forests, runoff areas, vernal depressions, roadsides.

Hot, shallow, quick-drying soils around thermal pools and vents.

Elevation

1800–2400(–2600) m. (5900–7900(–8500) ft.)

2200–2600 m. (7200–8500 ft.)

Distribution

CA; Mexico (Baja California)

[WildflowerSearch map]

Discussion

Plants of Erythranthe exigua are diminutive annuals with few nodes and greatly reduced leaves, corollas, and calyces, wide spreading pedicels, and lavender flowers with small but bilabiate limbs. The species is known only from the San Bernardino Mountains of San Bernardino County and in adjacent Mexico.

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

Erythranthe thermalis is endemic to Yellowstone National Park in northwestern Wyoming. The species is recognized by its annual duration (without rhizomes), reduced stature and leaf size, and short, but broad-limbed, corollas with autogamous fertilization. Typical E. guttata (rhizomatous, herkogamous) also grows in the immediately surrounding areas but apparently not in hot soils. Each species maintains distinctions in growth form, phenology and mating system in common garden experiments (Y. Lekberg et al. 2012).

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

Source

FNA vol. 17, p. 406.

FNA vol. 17, p. 413.

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. 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. tilingii, E. trinitiensis, E. unimaculata, E. utahensis, E. verbenacea, E. washingtonensis, E. willisii

Synonyms

Mimulus exiguus

Mimulus thermalis

Name authority

(A. Gray) G. L. Nesom & N. S. Fraga: Phytoneuron 2012-39: 42. (2012)

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

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

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Erythranthe exigua

Erythranthe thermalis

Erythranthe exigua

Erythranthe thermalis