Rumex mexicanus |
Rumex krausei |
|
---|---|---|
Mexican dock, Mexican willow, Mexican willow or dock |
Krause or Cape Krause sorrel, Krause's sorrel |
|
Habit | Plants perennial, glabrous; with vertical rootstock, occasionally with short, creeping rhizomes. | Plants perennial, glabrous, with thick, densely tufted underground stolons. |
Stems | erect or ascending, usually producing axillary shoots below 1st-order inflorescence or at proximal nodes, 30–60(–90) cm. |
erect or slightly ascending, 1 or several from base, sparsely branched in inflorescence,occasionally inflorescence simple or nearly so, 8–20(–25) cm; shoots usually densely crowded, not elongated. |
Leaves | blades light green to yellowish green, linear-lanceolate, occasionally lanceolate, 6–14 × 1–3.5(–4) cm, usually ca. 5–7 times as long as wide, widest near middle, thin, not coriaceous, base cuneate, margins entire, flat or undulate, apex acute or attenuate. |
ocrea brownish, membranous; blade narrowly linear or spatulate-lanceolate, not hastate (without basal lobes), 2.5–6 × 0.15–0.3(–0.4) cm, base narrowly cuneate (gradually narrowing into petiole), margins entire, flat or slightly revolute, apex obtuse or subacute. |
Inflorescences | terminal and axillary, terminal usually occupying distal 1/5–1/3 of stem, rather dense or interrupted in proximal 1/2, usually broadly paniculate (branches simple or with few 2d-order branches). |
terminal, occupying distal 1/2 of stem, usually dense, narrowly paniculate with branches directed upward, or simple. |
Pedicels | articulated in proximal 1/3 or almost near base, filiform (thickened distally), 4–7 mm, not more than 2–2.5 times as long as inner tepals, articulation indistinctly swollen. |
1–4 mm. |
Flowers | 10–20 in whorls; inner tepals broadly ovate-triangular, occasionally broadly triangular, 3.5–4.5(–5) × 3.5–4(–5) mm, base truncate or indistinctly cordate, margins entire or indistinctly erose, apex obtuse or subacute; tubercles 3, equal or subequal (much narrower than inner tepals). |
3–7 in whorls; inner tepals distinctly enlarged, 2.3–3 × 1.8–3 mm (free wing 0.4–0.8 mm wide), base cuneate, apex obtuse or subacute. |
Achenes | brown or dark reddish brown, 2–3 × 1.5–2 mm. |
light brown, 1.5–2 × 1.2–1.9 mm. |
2n | = 40. |
= 21. |
Rumex mexicanus |
Rumex krausei |
|
Phenology | Flowering spring–early summer. | Flowering summer. |
Habitat | Shores of streams and rivers, wet meadows | Clay and argillaceous soil, silty sand, rocky outcrops |
Elevation | 1000 m (3300 ft) | 0-300 m (0-1000 ft) |
Distribution |
NM; Mexico
|
AK; ne Asia (ne Russian Far East) |
Discussion | Some authors recognize Rumex mexicanus in the broad sense, including in it many other taxa treated here as separate entities. For consistency, the entities of the R. salicifolius aggregate that are recognized herein are kept separate pending additional taxonomic research. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
The name Rumex graminifolius was commonly misapplied to this species in northwestern North America and northeastern Eurasia. Rumex krausei is closely related to R. beringensis and probably represents the latter’s triploid race. Rumex krausei differs from R. beringensis in having larger flowers, fruiting inner tepals, and fruits, and shorter and less-branched or unbranched inflorescences. Rumex krausei occurs in eastern Chukotka, Russia, together with R. beringensis; however, it is believed to be confined mostly to clay soils and limestones. It has been reported from the Ogotoruk River on the northwestern coast of Alaska (B. A. Jurtzev et al. 1975) and some other Alaskan regions (western Seward Peninsula, capes Dyer and Thompson, and the Squirrel River). It may be expected anywhere within the range of R. beringensis. of conservation concern (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 5, p. 511. | FNA vol. 5, p. 500. |
Parent taxa | Polygonaceae > subfam. Polygonoideae > Rumex > subg. Rumex > sect. Axillares | Polygonaceae > subfam. Polygonoideae > Rumex > subg. Acetosella |
Sibling taxa | ||
Synonyms | Acetosella krausei | |
Name authority | Meisner: in A. P. de Candolle and A. L. P. P. de Candolle, Prodr. 14: 45. (1856) | Jurtzev & V. V. Petrovsky: Bot. Zhurn. (Moscow & Leningrad) 58: 1745. (1973) |
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