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Howell's violet, violette de Howell

kidney-leaf violet, Leconte violet, northern bog violet, violette néphrophylle

Habit Plants perennial, caulescent, not stoloniferous, 2–44 cm. Plants perennial, acaulescent, not stoloniferous, 5–15 cm; rhizome slender, becoming thick and fleshy with age.
Stems

1–4, ascending to erect (sometimes later reclining to nearly prostrate), glabrous or sparsely pubescent, on caudex from subligneous rhizome.

Leaves

basal and cauline;

basal: 1–6;

stipules linear-lanceolate to oblong, margins mostly entire or laciniate with gland-tipped projections, apex acute to acuminate;

petiole 4–15 cm, glabrous or sparsely puberulent;

blade ovate to reniform, 1.9–6.8 × 2.1–6.4 cm, thin, base cordate, margins crenate, ciliate, apex acute to usually obtuse, surfaces glabrous or sparsely puberulent;

cauline similar to basal except: stipules linear-lanceolate or deltate to oblong, apex acute or long-acuminate;

petiole 1–4.5 cm;

blade 2–5.1 × 1.2–5.8 cm.

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.

Peduncles

2.8–17.8 cm, glabrous or sparsely pubescent.

3–25 cm, usually glabrous.

Flowers

sepals lanceolate, margins ciliate or eciliate, auricles 1–2 mm;

petals violet to soft blue-violet on both surfaces, whitish basally, lower 3 dark violet-veined, lateral 2 densely bearded, lowest 14–23 mm, spur blue-violet to whitish, gibbous to elongated, 2.4–5 mm, usually less than 1/2 lowest petal, tip straight;

style head bearded; cleistogamous flowers axillary.

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.

Capsules

ellipsoid, 7–11 mm, glabrous.

ovoid, 5–10 mm, glabrous.

Seeds

light brown, 2.1–2.8 mm.

beige to brown or dark brown, 1.5–2.5 mm.

2n

= 40, 80.

= 54.

Viola howellii

Viola nephrophylla

Phenology Flowering Apr–Jul. Flowering Jan–Sep.
Habitat Moist, shady areas, coniferous forests, prairies, along streams Wet habitats in saturated soil in prairies, pastures, bogs, fens, sedge meadows, rocky shores of lakes and streams, limestone outcrops, gravelly calcareous stream beds
Elevation 50–1500 m (200–4900 ft) 100–3000 m (300–9800 ft)
Distribution
from FNA
CA; OR; WA; BC
[WildflowerSearch map]
[BONAP county map]
from FNA
AR; AZ; CA; CO; CT; IA; ID; IL; KS; MA; ME; MI; MN; MT; ND; NE; NH; NM; NV; NY; OH; OR; PA; SD; TX; UT; VT; WA; WI; WV; WY; AB; BC; MB; NB; NF; NS; NT; NU; ON; PE; QC; SK; YT
[WildflowerSearch map]
[BONAP county map]
Discussion

Viola howellii is similar to V. adunca and usually occupies moister habitats along the western side of the Cascade Mountains (H. E. Ballard 1992). The first documented record of this species in California was recently reported from Siskiyou County (R. J. Little 2010).

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

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.)

Source FNA vol. 6, p. 134. FNA vol. 6, p. 139.
Parent taxa Violaceae > Viola Violaceae > Viola
Sibling taxa
V. adunca, V. affinis, V. arvensis, V. bakeri, V. beckwithii, V. bicolor, V. biflora, V. blanda, V. brittoniana, V. canadensis, V. canina, V. charlestonensis, V. clauseniana, V. cucullata, V. cuneata, V. douglasii, V. egglestonii, V. epipsila, V. flettii, V. frank-smithii, V. glabella, V. guadalupensis, V. hallii, V. hastata, V. hirsutula, V. japonica, V. labradorica, V. lanceolata, V. langsdorffii, V. lithion, V. lobata, V. macloskeyi, V. missouriensis, V. nephrophylla, V. novae-angliae, V. nuttallii, V. ocellata, V. odorata, V. orbiculata, V. palmata, V. palustris, V. pedata, V. pedatifida, V. pedunculata, V. pinetorum, V. praemorsa, V. primulifolia, V. prionantha, V. pubescens, V. purpurea, V. quercetorum, V. renifolia, V. riviniana, V. rostrata, V. rotundifolia, V. sagittata, V. selkirkii, V. sempervirens, V. septemloba, V. sheltonii, V. sororia, V. striata, V. subsinuata, V. tomentosa, V. tricolor, V. trinervata, V. tripartita, V. umbraticola, V. utahensis, V. vallicola, V. villosa, V. walteri
V. adunca, V. affinis, V. arvensis, V. bakeri, V. beckwithii, V. bicolor, V. biflora, V. blanda, V. brittoniana, V. canadensis, V. canina, V. charlestonensis, V. clauseniana, V. cucullata, V. cuneata, V. douglasii, V. egglestonii, V. epipsila, V. flettii, V. frank-smithii, V. glabella, V. guadalupensis, V. hallii, V. hastata, V. hirsutula, V. howellii, V. japonica, V. labradorica, V. lanceolata, V. langsdorffii, V. lithion, V. lobata, V. macloskeyi, V. missouriensis, V. novae-angliae, V. nuttallii, V. ocellata, V. odorata, V. orbiculata, V. palmata, V. palustris, V. pedata, V. pedatifida, V. pedunculata, V. pinetorum, V. praemorsa, V. primulifolia, V. prionantha, V. pubescens, V. purpurea, V. quercetorum, V. renifolia, V. riviniana, V. rostrata, V. rotundifolia, V. sagittata, V. selkirkii, V. sempervirens, V. septemloba, V. sheltonii, V. sororia, V. striata, V. subsinuata, V. tomentosa, V. tricolor, V. trinervata, V. tripartita, V. umbraticola, V. utahensis, V. vallicola, V. villosa, V. walteri
Synonyms V. arizonica, V. austiniae, V. cognata, V. crassula, V. galacifolia, V. lunellii, V. mccabeiana, V. nephrophylla var. arizonica, V. nephrophylla var. cognata, V. peramoena, V. pratincola, V. prionosepala, V. retusa, V. subjuncta, V. vagula
Name authority A. Gray: Proc. Amer. Acad. Arts 22: 308. (1887) Greene: Pittonia 3: 144. (1896)
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