Rumex mexicanus

Meisner in A. P. de Candolle and A. L. P. P. de Candolle

in A. P. de Candolle and A. L. P. P. de Candolle, Prodr. 14: 45. 1856.

Common names: Mexican willow or dock
Treatment appears in FNA Volume 5. Treatment on page 511. Mentioned on page 493, 505, 510, 512.

Plants perennial, glabrous; with vertical rootstock, occasionally with short, creeping rhizomes. Stems erect or ascending, usually producing axillary shoots below 1st-order inflorescence or at proximal nodes, 30–60 (–90) cm. Leaf-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. 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). 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. 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). Achenes brown or dark reddish-brown, 2–3 × 1.5–2 mm. 2n = 40.


Phenology: Flowering spring–early summer.
Habitat: Shores of streams and rivers, wet meadows
Elevation: 1000 m

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.

Selected References

None.

Lower Taxa

None.

"/2" is not declared as a valid unit of measurement for this property."+-2.5timesaslongasinnertepals" is not declared as a valid unit of measurement for this property.

... more about "Rumex mexicanus"
unwinged +  and weakly winged +
dark reddish-brown;brown +
0.2 cm2 mm <br />0.002 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
pyramidal +, compressed-3-gonous +  and 3-gonous +
1.5mm;2mm +
yellow +  and brownish yellow +
ovate +  and elongate +
subacute;obtuse;attenuate;acute +
Sergei L. Mosyakin +
Meisner in A. P. de Candolle and A. L. P. P. de Candolle +
leafy +  and regular +
not articulated +
cordate +, truncate +  and cuneate +
crisped;undulate;flat;crisped;undulate;flat +
foliaceous +  and perfoliate +
scale-like +
tuberculate +
just below the soil surface or and above the soil surface +  and spreading +
Mexican willow or dock +
N.Mex. +  and Mexico +
1000 m +
free +  and distinct +
unisexual +, bisexual +  and , +
disarticulating +  and solid +
decumbent to erect +  and prostrate +
unwinged +  and winged +
black +, red +, brown +  and yellowish +
exserted +  and included +
pubescent +  and glabrous +
spheroidal +, 4-gonous +, lenticular +, biconvex +, discoid +, 3-gonous +  and 2-gonous +
Shores of streams and rivers, wet meadows +
0.45 cm4.5 mm <br />0.0045 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
0.4 cm4 mm <br />0.004 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
0.35 cm3.5 mm <br />0.0035 m <br /> (0.45 cm4.5 mm <br />0.0045 m <br />) +
always distinctly wider and longer +
triangular +  and ovate-triangular +
3.5mm +  and 4mm +
nonmembranous +
3.5 cm35 mm <br />0.035 m <br /> (4 cm40 mm <br />0.04 m <br />) +
light green +  and yellowish green +
6 cm60 mm <br />0.06 m <br /> (14 cm140 mm <br />0.14 m <br />) +
lanceolate +  and linear-lanceolate +
not coriaceous +
widest;1cm;3.5cm +
deciduous +
cauline +  and basal +
erose +  and entire +
pubescent +  and glabrous +
undulate +, flat +  and entire +
smaller +
narrower +
swollen +
partly +  and foliaceous +
deciduous +  and persistent +
cylindric +
membranous +
anatropous +, , +  and orthotropous +
accrescent +
0.4 cm4 mm <br />0.004 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
spreading;erect +
red;pinkish;red;pinkish;green +
campanulate +
accrescent +
fleshy +, indurate +  and membranous +
Flowering spring–early summer. +
(2-)3(-4)-carpellate +
60 cm600 mm <br />0.6 m <br /> (90 cm900 mm <br />0.9 m <br />) +
30 cm300 mm <br />0.3 m <br /> (60 cm600 mm <br />0.6 m <br />) +
in A. P. de Candolle and A. L. P. P. de Candolle, Prodr. +
slender;stout +
not scapose +
decumbent +  and procumbent +
ascending +  and erect +
papillose-pubescent +  and glabrous +
1/5 +  and 1/3 +
plumose +  and fimbriate +
deciduous +  and persistent +
2-lobed +  and cylindric +
coriaceous +  and membranous +
distinct +
reflexed;spreading +
spreading;erect +
Undefined subg. Lapathum +, Rumex sect. Lapathum +  and Rumex subg. Lapathum +
Rumex mexicanus +
Rumex sect. Axillares +
species +
lobed +  and laciniate +
coriaceous +
persistent +
membranous +
pubescent +  and glabrous +
stoloniferous +  and rhizomatous +
10 +, 9 +, 8 +  and 7 +