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Howell's violet, violette de Howell

Clausen's violet

Habit Plants perennial, caulescent, not stoloniferous, 2–44 cm. Plants perennial, acaulescent, not stoloniferous, 3–20 cm; rhizome short, slender, fleshy.
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, 2–10, often prostrate, sometimes ascending;

stipules narrowly lanceolate, margins faintly glandular-toothed, apex acute or obtuse;

petiole 5–11 cm, glabrous;

blade unlobed, ± deltate, 3–5 × 4–5 cm, base ± truncate, margins serrate, ciliate or eciliate, apex obtuse, surfaces usually glabrous, sometimes sparsely pubescent abaxially.

Peduncles

2.8–17.8 cm, glabrous or sparsely pubescent.

8–14 cm, 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 lanceolate to ovate, margins eciliate or ciliate around auricles, auricles 1–2 mm;

petals light violet on both surfaces, lower 3 purple-veined, all beardless, lowest petal 8–20 mm, spur white, gibbous, 2–3 mm;

style head beardless; cleistogamous flowers on prostrate to ascending peduncles.

Capsules

ellipsoid, 7–11 mm, glabrous.

oblong, 8–10 mm, glabrous.

Seeds

light brown, 2.1–2.8 mm.

dark brown to black, 1.2–2 mm.

2n

= 40, 80.

= 44.

Viola howellii

Viola clauseniana

Phenology Flowering Apr–Jul. Flowering Apr–Jun.
Habitat Moist, shady areas, coniferous forests, prairies, along streams Hanging gardens, seeps, springs, shady areas
Elevation 50–1500 m (200–4900 ft) 1600 m (5200 ft)
Distribution
from FNA
CA; OR; WA; BC
[WildflowerSearch map]
[BONAP county map]
from FNA
UT
[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.)

Of conservation concern.

Viola clauseniana is endemic to Zion National Park, Washington County. M. S. Baker reported that its seeds were minutely roughed, a characteristic not recorded for other Viola species. Viola clauseniana was originally thought to be closely related to the acaulescent blue violets, most notably V. nephrophylla (S. L. Welsh et al. 1987; L. E. McKinney 1992). After contemplating the 2n = 44 chromosome count obtained by J. Clausen (1964), H. E. Ballard (pers. comm.) suggested that V. clauseniana might be more closely related with the stemless white violets (for example, V. blanda) than with V. nephrophylla. Viola clauseniana was considered a distinct species by N. H. Holmgren (2005d) and T. Marcussen and T. Karlsson (2010).

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

Source FNA vol. 6, p. 134. FNA vol. 6, p. 128.
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. 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. 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
Name authority A. Gray: Proc. Amer. Acad. Arts 22: 308. (1887) M. S. Baker: Madroño 4: 194. (1938)
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