Viola nephrophylla
Viola sororia
kidney-leaf violet, Leconte violet, northern bog violet, violette néphrophylle
common blue violet, common or downy or woolly blue violet, northern blue violet, northern violet, northern woodland violet, violette parente, woolly blue violet
basal, 4–7, ascending to erect;
stipules lanceolate, margins entire or fimbriate, apex acute;
petiole 2–25 cm, usually glabrous;
blade usually grayish green or purplish green abaxially, unlobed, ovate, reniform, or broadly reniform to orbiculate, 1–7 × 1–7 cm, somewhat fleshy, base broadly cordate or reniform to ± truncate, margins crenate to serrate, ciliate or eciliate, apex acute to obtuse or rounded, surfaces usually glabrous, rarely sparsely pubescent.
basal, 1–8, ascending to erect;
stipules linear-lanceolate to broadly lanceolate, margins entire, sometimes glandular distally, apex acute;
petiole 2–25 cm, pubescent or glabrous;
blade green abaxially, unlobed, ovate or broadly ovate to reniform, 2–5 × 2–10 cm, not fleshy, base cordate, margins crenate to serrate, ciliate or eciliate, apex acute to obtuse or rounded, surfaces usually pubescent, rarely glabrous.
3–25 cm, usually glabrous.
3–25 cm, glabrous or sparsely pubescent.
sepals ovate, margins usually eciliate, auricles 1–2 mm;
petals deep bluish violet on both surfaces, lower 3 white basally and darker violet-veined, lateral 2 bearded, upper 2 sometimes sparsely bearded, lowest densely bearded or beardless, 10–28 mm, spur same color as petals, gibbous, 2–3 mm;
style head beardless; cleistogamous flowers on erect to ascending peduncles.
sepals lanceolate to ovate, margins ciliate or eciliate, auricles 1–2 mm;
petals light to dark blue- or dark purple-violet, reddish purple, or rarely white on both surfaces, usually white basally, lowest and sometimes lateral 2 purple-veined, lateral 2 bearded, lowest bearded or beardless, 15–25 mm, spur same color as petals, gibbous, 2–3 mm;
style head beardless; cleistogamous flowers on prostrate to ascending peduncles.
ovoid, 5–10 mm, glabrous.
ellipsoid, 5–12 mm, glabrous.
beige to brown or dark brown, 1.5–2.5 mm.
beige, mottled to bronze, 1.5–2.5 mm.
= 54.
= 54.
Viola nephrophylla
Viola sororia
Viola nephrophylla has the widest distribution in North America of any of the acaulescent blue violets.
There is some question whether the species we now know as Viola nephrophylla fits with the protologue and type specimen(s). McKinney examined the type designated by Greene; it appears that what most botanists have called V. nephrophylla may be an undescribed taxon. N. L. Gil-Ad (1997) believed Greene’s type contained plants that were genetically impure based on seed coat micromorphology and suggested the specimens might be a mixture of both orthospecies and introgressants.
Viola mccabeiana was described by M. S. Baker in 1940 from collections made in British Columbia. Later, Baker (1949b) discussed the reasons why the name V. mccabeiana needed to be abandoned. C. L. Hitchcock et al. (1955–1969, vol. 3) treated V. mccabeiana as synonymous with V. nephrophylla var. cognata. While Viola mccabeiana is recognized in Canada (L. Brouillet et al., http://data.canadensys.net/vascan/), we believe it is best included within V. nephrophylla.
Viola nephrophylla reportedly hybridizes with V. cucullata (= V. ×insessa House), V. sororia var. sororia (= V. ×napae House), and V. affinis (= V. ×subaffinis House).
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Viola sororia is similar to V. palmata in the high degree of phenotypic plasticity. The petal color is usually light to dark blue-violet. In V. sororia forma priceana (the Confederate violet) petals are grayish white with violet veins. Viola septentrionalis was recognized by N. L. Gil-Ad (1997) based on what he considered distinct capsule and seed morphology. His assumptions were based on one to four specimens. A. Haines (2011) alluded to the variability of V. sororia and indicated that a more northern form has often been called V. septentrionalis. He suggested that range-wide patterns of variation make it difficult or impractical to separate. We currently see no valid reason to recognize V. septentrionalis.
Viola floridana was recognized by D. B. Ward (2006) as distinct from V. sororia based on being glabrous except for scattered hairs on petioles.
Viola sororia reportedly hybridizes with V. cucullata (= V. ×bissellii House), V. hirsutula [= V. ×cordifolia (Nuttall) Schweinitz], V. pedatifida var. brittoniana (= V. ×insolita House), V. pedatifida var. pedatifida (= V. ×bernardii Greene), and V. sagittata var. sagittata (= V. ×conjugens Greene).
(Discussion copyrighted by Flora of North America; reprinted with permission.)
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