FNA: Braya humilis subsp. humilis vs. Braya humilis subsp. porsildii

	Braya humilis subsp. humilis	Braya humilis subsp. porsildii
	dwarf braya	Porsild's dwarf braya
Stems	ascending to erect, branched or unbranched, 0.4–3.3 dm, sparsely to moderately pubescent.	ascending to erect or, rarely, decumbent, usually unbranched, 0.3–1.7(–2.5) dm, densely pubescent.
Leaves	blade margins sinuate-dentate, shallowly pinnatifid, or entire, surfaces moderately pubescent.	blade margins usually entire, sometimes weakly sinuate-dentate, surfaces densely pubescent.
Flowers	petals white, pink, or purple, 2.5–6.9(–7.5) × (0.7–)0.9–4(–4.2) mm.	petals white, 4.4–6.9 × (1.9–)2.3–4.2 mm.
Fruits	usually fertile and fully developed, somewhat torulose, 0.6–1.2(–1.3) mm wide; septum not fenestrate or split longitudinally.	often abortive, somewhat torulose, 0.8–1.2 mm wide when fully developed; septum not fenestrate or split longitudinally.
2n	= 28, 42, 56, 70.	= 28.

	Braya humilis subsp. humilis	Braya humilis subsp. porsildii
Phenology	Flowering May–Jul.	Flowering May–Jul.
Habitat	Sandy, gravelly soil along streams, lakeshores, roadsides, moraines, open stony slopes, dolomite cliffs and slopes, limestone ledges, solifluction soils	Dry alpine scree slopes, glacial moraines, and gravel bars, often on limestone gravels and soils
Elevation	0-4000 m (0-13100 ft)	500-3000 m (1600-9800 ft)
Distribution	AK; CO; MI; MT; VT; WY; AB; BC; MB; NF; NT; NU; ON; QC; YT; Greenland; e Asia; c Asia [BONAP county map]	AB; BC; NT [BONAP county map]
Discussion	Subspecies humilis is extremely variable morphologically. In a general way, morphological form correlates with ploidy level, e.g., tetraploids, octoploids, and decaploids tend to be short in stature with small leaves. Hexaploids are less predictable. They range from short plants with small leaves to large, robust, multi-branched plants with large, pinnatifid leaves. Attempting to segregate most morphological forms of Braya humilis into logical infraspecific taxa is an exercise in futility. Populations that appear distinctive in the field almost always blur imperceptibly into the larger subsp. humilis continuum when compared with other populations from across the range of distribution. Subspecies humilis is broadly distributed on calcareous substrates in arctic, subarctic, alpine, and boreal regions of North America and Asia. (Discussion copyrighted by Flora of North America; reprinted with permission.)	Subspecies maccallae and porsildii share the large flowers, high percentage of abortive fruits, and leaf margins mostly entire, but they differ in indumentum and habitats. (Discussion copyrighted by Flora of North America; reprinted with permission.)
Source	FNA vol. 7, p. 549.	FNA vol. 7, p. 550.
Parent taxa	Brassicaceae > tribe Euclidieae > Braya > Braya humilis	Brassicaceae > tribe Euclidieae > Braya > Braya humilis
Sibling taxa	B. humilis subsp. ellesmerensis, B. humilis subsp. maccallae, B. humilis subsp. porsildii	B. humilis subsp. ellesmerensis, B. humilis subsp. humilis, B. humilis subsp. maccallae
Synonyms	Arabidopsis novae-angliae, B. humilis var. abbei, B. humilis subsp. arctica, B. humilis var. arctica, B. humilis var. interior, B. humilis var. laurentiana, B. humilis var. leiocarpa, B. humilis var. novae-angliae, B. humilis subsp. richardsonii, B. humilis subsp. ventosa, B. humilis var. ventosa, B. intermedia, B. novae-angliae, B. novae-angliae subsp. abbei, B. novae-angliae var. interior, B. novae-angliae var. laurentiana, B. novae-angliae subsp. ventosa, B. richardsonii, Pilosella novae-angliae, Pilosella richardsonii, Torularia humilis subsp. arctica
Name authority	unknown	J. G. Harris: Novon 16: 348. (2006)
Web links	Local floras: BC Local Web sites: MI Flora, PNW Herbaria WildflowerSearch iNaturalist (observations) LBJ Wildflower Center SEINet Plants of the World Online Encyclopedia of Life Wikipedia Google Image Search	Local floras: BC Local Web sites: PNW Herbaria WildflowerSearch iNaturalist (observations) USDA Plants Database LBJ Wildflower Center SEINet Plants of the World Online Encyclopedia of Life Wikipedia Google Image Search

Braya humilis subsp. porsildii

dwarf braya

Porsild's dwarf braya

Stems

ascending to erect, branched or unbranched, 0.4–3.3 dm, sparsely to moderately pubescent.

ascending to erect or, rarely, decumbent, usually unbranched, 0.3–1.7(–2.5) dm, densely pubescent.

Leaves

blade margins sinuate-dentate, shallowly pinnatifid, or entire, surfaces moderately pubescent.

blade margins usually entire, sometimes weakly sinuate-dentate, surfaces densely pubescent.

Flowers

petals white, pink, or purple, 2.5–6.9(–7.5) × (0.7–)0.9–4(–4.2) mm.

petals white, 4.4–6.9 × (1.9–)2.3–4.2 mm.

Fruits

usually fertile and fully developed, somewhat torulose, 0.6–1.2(–1.3) mm wide;

septum not fenestrate or split longitudinally.

often abortive, somewhat torulose, 0.8–1.2 mm wide when fully developed;

septum not fenestrate or split longitudinally.

= 28, 42, 56, 70.

= 28.

Braya humilis subsp. porsildii

Phenology

Flowering May–Jul.

Habitat

Sandy, gravelly soil along streams, lakeshores, roadsides, moraines, open stony slopes, dolomite cliffs and slopes, limestone ledges, solifluction soils

Dry alpine scree slopes, glacial moraines, and gravel bars, often on limestone gravels and soils

Elevation

0-4000 m (0-13100 ft)

500-3000 m (1600-9800 ft)

Distribution

AK; CO; MI; MT; VT; WY; AB; BC; MB; NF; NT; NU; ON; QC; YT; Greenland; e Asia; c Asia

[BONAP county map]

AB; BC; NT

[BONAP county map]

Discussion

Subspecies humilis is extremely variable morphologically. In a general way, morphological form correlates with ploidy level, e.g., tetraploids, octoploids, and decaploids tend to be short in stature with small leaves. Hexaploids are less predictable. They range from short plants with small leaves to large, robust, multi-branched plants with large, pinnatifid leaves. Attempting to segregate most morphological forms of Braya humilis into logical infraspecific taxa is an exercise in futility. Populations that appear distinctive in the field almost always blur imperceptibly into the larger subsp. humilis continuum when compared with other populations from across the range of distribution. Subspecies humilis is broadly distributed on calcareous substrates in arctic, subarctic, alpine, and boreal regions of North America and Asia.

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

Subspecies maccallae and porsildii share the large flowers, high percentage of abortive fruits, and leaf margins mostly entire, but they differ in indumentum and habitats.

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

Source

FNA vol. 7, p. 549.

FNA vol. 7, p. 550.

Parent taxa

Brassicaceae > tribe Euclidieae > Braya > Braya humilis

Sibling taxa

B. humilis subsp. ellesmerensis, B. humilis subsp. maccallae, B. humilis subsp. porsildii

B. humilis subsp. ellesmerensis, B. humilis subsp. humilis, B. humilis subsp. maccallae

Synonyms

Arabidopsis novae-angliae, B. humilis var. abbei, B. humilis subsp. arctica, B. humilis var. arctica, B. humilis var. interior, B. humilis var. laurentiana, B. humilis var. leiocarpa, B. humilis var. novae-angliae, B. humilis subsp. richardsonii, B. humilis subsp. ventosa, B. humilis var. ventosa, B. intermedia, B. novae-angliae, B. novae-angliae subsp. abbei, B. novae-angliae var. interior, B. novae-angliae var. laurentiana, B. novae-angliae subsp. ventosa, B. richardsonii, Pilosella novae-angliae, Pilosella richardsonii, Torularia humilis subsp. arctica

Name authority

unknown

J. G. Harris: Novon 16: 348. (2006)

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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Flora of North America species comparison

Braya humilis subsp. humilis

Braya humilis subsp. porsildii

Braya humilis subsp. humilis

Braya humilis subsp. porsildii