Epilobium anagallidifolium |
Epilobium rigidum |
|
|---|---|---|
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alpine willow-herb, pimpernel willow-herb, épilobe à feuilles de mouron |
rigid willowherb, Siskiyou Mountains willowherb, stiff willowherb |
|
| Habit | Herbs with spreading thin, small-leafed epigeous soboles to 5 cm. | Herbs from woody caudex forming hypogeal shoots with barklike periderm. |
| Stems | many, ascending, often sigmoidally bent, nodding distally, later erect, clumped or mat-forming, terete, 3–20(–25) cm, simple, subglabrous, sometimes with faint raised strigillose lines decurrent from margins of petioles, rarely mixed strigillose and sparsely glandular puberulent distally. |
several to many, suberect or ascending, terete, 10–40 cm, simple or sparsely branched, usually glabrous and ± glaucous proximal to inflorescence, strigillose distally, sometimes densely strigillose throughout. |
| Leaves | opposite and crowded proximal to inflorescence, alternate distally, petioles 1–6 mm, rarely subsessile distally; blade spatulate to oblong proximally, elliptic to narrowly lanceolate or sublinear distally, (0.5–)0.8–2.5 × 0.3–1 cm, base attenuate to cuneate, margins subentire proximally, sparsely denticulate distally with 2–5 low teeth per side, veins obscure, 2–4 per side, apex obtuse or rounded proximally to subacute distally, surfaces subglabrous; bracts reduced, usually much narrower. |
crowded distally, petiole 2–6 mm, blade narrowly ovate to ovate or broadly elliptic, often obovate in proximal pairs; cauline 2–4.5 × 0.8–2 cm, base rounded to attenuate, margins subentire or finely denticulate, 8–12 teeth per side, lateral veins inconspicuous, 3–5 per side, apex obtuse proximally to subacute distally, surfaces glaucous and subglabrous to densely strigillose; bracts narrower and much smaller. |
| Inflorescences | nodding in bud, later suberect, few-flowered racemes, subglabrous to sparsely strigillose and/or glandular puberulent. |
erect racemes, simple, ± densely strigillose, rarely mixed sparsely glandular puberulent. |
| Flowers | suberect; buds 2–5 × 1–2 mm; pedicel 1–6(–15) mm; floral tube 0.6–1.2 × 0.8–1.8 mm, slightly raised subglabrous ring at mouth inside; sepals green to reddish purple, 1.5–5 × 0.6–1.5 mm, abaxial surface subglabrous to sparsely glandular; petals usually pink to rose-purple, rarely white, narrowly obcordate, (1.7–)2.5–6.5(–8) × 1.6–3.5 mm, apical notch 0.5–1.2 mm; filaments cream to light pink, those of longer stamens 1.4–3.2 mm, those of shorter ones 0.7–2 mm; anthers 0.3–0.6 × 0.2–0.4 mm; ovary often reddish purple, 6–20 mm, subglabrous or sparsely strigillose and glandular puberulent; style white, 1.2–2.5 mm, glabrous, stigma broadly clavate to subcapitate, entire, 0.9–1.5 × 0.4–0.7 mm, surrounded by longer anthers. |
erect; buds 6–11 × 4–5 mm, apiculate; pedicels 4–8 mm; floral tube 1–1.8 × 2–3 mm, with raised ring of tissue edged with spreading hairs at mouth inside; sepals often reddish green, lanceolate, 9.5–14.5 × 2.5–3.5 mm, apex acuminate, abaxial surface densely strigillose; petals pink to rose-purple, obcordate, 16–20 × 13–16 mm, apical notch 3.4–5.5 mm; filaments light pink, those of longer stamens 9–14 mm, those of shorter ones 6.5–10 mm; anthers cream, 1.8–3.5 × 1–1.9 mm; ovary 6–12 mm, densely strigillose; style cream to light pink, 14.5–18.5 mm, stigma broadly 4-lobed, 1–1.5 × 3–3.5 mm, exserted beyond anthers. |
| Capsules | slender, often reddish purple, 17–40(–55) mm, surfaces subglabrous or with scattered hairs; pedicel 5–35(–68) mm. |
20–35 mm, surfaces strigillose; pedicel 9–13 mm, bracts often attached 2–3 mm from base. |
| Seeds | narrowly obovoid, 0.7–1.4 × 0.3–0.5 mm, inconspicuous chalazal collar 0.1–0.2 mm wide, light brown, surface reticulate (smooth); coma persistent, dull white, 2–4 mm. |
narrowly obovoid, constriction 0.6–0.8 mm from micropylar end, 2.5–3.4 × 0.9–1.4 mm, chalazal collar obscure, light brown, surface papillose; coma easily detached, white, 6–8 mm. |
| 2n | = 36. |
= 36. |
Epilobium anagallidifolium |
Epilobium rigidum |
|
| Phenology | Flowering Jun–Sep. | Flowering Jul–Sep. |
| Habitat | Moist flats, stream banks, subarctic coastal marsh edges, high montane and alpine meadows and seeps. | Dry rocky or sandy benches, rocky hillsides, dry streambeds in coniferous forests, on seasonally moist serpentine slopes, rarely along disturbed roadsides. |
| Elevation | 0–4500 m. [0–14800 ft.] | 100–1200(–1500) m. [300–3900(–4900) ft.] |
| Distribution |
AK; CA; CO; ID; ME; MT; NH; NV; OR; UT; WA; WY; AB; BC; NL; NT; NU; QC; YT; Greenland; Eurasia
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CA; OR
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| Discussion | Epilobium anagallidifolium is widely but sparsely distributed in high montane-alpine and subarctic Eurasia, including Europe, Russia, China, and Japan. Epilobium anagallidifolium usually forms low clumps or mats, with stems nodding in bud and usually subglabrous below the inflorescence. Many collections of E. anagallidifolium from eastern Canada and Greenland tend to be unusually tall (to 25 cm) and robust for the species, with somewhat larger, thicker leaves, and longer pedicels (to 60 mm). Similarly large and robust specimens occur scattered in Yukon and Washington, and may result from occasional hybridization and introgression with sympatric species such as E. hornemannii or E. lactiflorum, which also have the CC chromosomal arrangement. In an analysis of Fennoscandian populations of the Alpinae group, I. Kytövuori (1972) found a similar pattern of mostly smaller, sigmoidal plants of E. anagallidifolium with a small proportion of larger ones, and he also suggested the possibility of hybridization and/or introgression. Plants of Epilobium anagallidifolium, and indeed of the whole Alpinae group, from Haida Gwaii (the Queen Charlotte Islands) of British Columbia (J. A. Calder and R. L. Taylor 1968), are particularly distinctive compared to those on the mainland, and difficult to interpret. The observed differences may be the result of hybridization with other sympatric species or a response to unique ecological conditions on the islands, reinforced by relative isolation from mainland British Columbia. The Linnaean name Epilobium alpinum has long been a source of nomenclatural confusion and instability, since it circumscribed at least four distinct species, especially E. anagallidifolium. A proposal by P. C. Hoch et al. (1995) to permanently reject the name E. alpinum Linnaeus was approved. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Within its range in northwestern California and southwestern Oregon, Epilobium rigidum is restricted to unusually dry habitats compared to most species in sect. Epilobium, but is not unlike taxa in the non-n = 18 clade, which are both perennial and annual. It is self-compatible, but with strongly protandrous flowers and an exserted stigma, and is modally outcrossing, pollinated by bees and flies. Plant vestiture varies from subglabrous to densely strigillose throughout (var. canescens), but plants with these differences can be in the same population, and no other morphological differences between them have been found. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
| Parent taxa | ||
| Sibling taxa | ||
| Synonyms | E. alpinum, E. pseudoscaposum | E. rigidum var. canescens |
| Name authority | Lamarck in J. Lamarck et al.: Encycl. 2: 376. (1786) | Haussknecht: Oesterr. Bot. Z. 29: 51. (1879) |
| Source | FNA vol. 10. | FNA vol. 10. |
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