Malvastrum coromandelianum

(Linnaeus) Garcke

Bonplandia (Hanover) 5: 295. 1857.

Common names: Common false mallow
Illustrated
Basionym: Malva coromandeliana Linnaeus Sp. Pl. 2: 687. 1753
Synonyms: Malvastrum lindheimerianum (Scheele) Walpers
Treatment appears in FNA Volume 6. Treatment on page 297. Mentioned on page 294, 295.

Herbs, annual or perennial, 0.2–0.6 (–1) m, with 1 main-stem, freely branching in proximal 1/2. Stems erect or decumbent, hairs scattered, appressed, bilateral, (2–) 4-rayed, swollen-based, not sublepidote, hairs 1–3 mm. Leaves: stipules persistent, lanceolate, subfalcate to falcate, 3–6 × 0.5–1 mm, apex acuminate; petiole 10–20 (–40) mm; blade ovate to ± lanceolate, unlobed, (1.7–) 3–4 (–6.5) × (0.6–) 1.5–3 (–5.5) cm, 1.1–2.8 times longer than wide, 2.5–4.5 times longer than petiole, not greatly reduced on stem distally, base truncate to broadly-rounded to often wide-cuneate, margins dentate to serrate, apex acute, surfaces sparsely hairy, hairs bilateral, 2–4-rayed, stellate or with simple hairs on adaxial surface. Inflorescences axillary, solitary flowers, flowers sometimes congested towards branch tips; floral bracts absent. Pedicels 1–2 mm, to 3–5 mm in fruit; involucellar bractlets basally adnate to calyx for 0.5–1 mm, lanceolate, subfalcate, 4–6 × 0.6–1 mm, shorter than calyx lobes, apex acute.


Phenology: Flowering spring–frost at northern limit as an annual (cold-sensitive), nearly year-round when sufficiently wet and warm as a perennial.
Habitat: River floodplains and banks, disturbed areas, often in alkaline soil
Elevation: 0–100 m

Distribution

V6 539-distribution-map.jpg

Fla., La., Tex., Mexico, West Indies, Central America, South America (to Argentina), worldwide from Tropics and subtropics to warm temperate zones

Discussion

Malvastrum coromandelianum is a widespread weed and the most common species in the genus; it is apparently native from Texas to Argentina. The introduced and widespread form has simple hairs on the adaxial surface of the leaf, while the native form has stellate hairs on that surface. Both forms are found in Texas. The species historically has been introduced in ballast in Alabama, Massachusetts, Pennsylvania, and New Jersey, but did not persist.

Subspecies coromandelianum occurs in the flora area and is a widespread weed in tropical and warm-temperate areas worldwide; the other two subspecies occur only in South America and on the Galapagos Islands.

Selected References

None.

Lower Taxa

None.
0.01 cm0.1 mm <br />1.0e-4 m <br /> (0.23 cm2.3 mm <br />0.0023 m <br />) +
Steven R. Hill +
(Linnaeus) Garcke +
wide-cuneate +, truncate +  and broadly-rounded +
Malva coromandeliana +
4 cm40 mm <br />0.04 m <br /> (6.5 cm65 mm <br />0.065 m <br />) +
3 cm30 mm <br />0.03 m <br /> (5.5 cm55 mm <br />0.055 m <br />) +
3 cm30 mm <br />0.03 m <br /> (4 cm40 mm <br />0.04 m <br />) +
2.5-4.5 times longer than petiole +
unlobed +, ovate +  and more or less lanceolate +
reduced +
1.5cm;3cm +
0.4 cm4 mm <br />0.004 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
subfalcate +  and lanceolate +
0.06 cm0.6 mm <br />6.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
not inflated +
accrescent +
indehiscent +  and loculicidal +
Common false mallow +
yellow +  and yellow-orange +
widespreading +
Fla. +, La. +, Tex. +, Mexico +, West Indies +, Central America +, South America (to Argentina) +  and worldwide from Tropics and subtropics to warm temperate zones +
0–100 m +
sparse;copious +
pistillate +  and staminate +
unisexual +  and bisexual +
depressed +  and not inflated +
River floodplains and banks, disturbed areas, often in alkaline soil +
simple +  and swollen-based +
bilateral +  and scattered +
with simple hairs +  and stellate +
pustular-based +
0.1 cm1 mm <br />0.001 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
tough-fibrous +
connate +  and distinct +
simple +, stipulate +, sessile +, subsessile +  and petiolate +
distichous +  and alternate +
deltate +  and narrowly triangular +
denticulate;dentate-serrate +
Brown (?) +, Tan (?) +  and Drying (?) +
dehiscent +  and indehiscent +
glabrous +  and hairy +
wedge--shaped +
(5-)8-18-carpellate +
0.3 cm3 mm <br />0.003 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
adnate +  and distinct +
2 cm20 mm <br />0.02 m <br /> (4 cm40 mm <br />0.04 m <br />) +
1 cm10 mm <br />0.01 m <br /> (2 cm20 mm <br />0.02 m <br />) +
Flowering spring–frost at northern limit as an annual (cold-sensitive), nearly year-round when sufficiently wet and warm as a perennial. +
Bonplandia (Hanover) +
reniform +
persistent +
Illustrated +
sessile +  and subsessile +
decumbent;erect +
filiform +, linear +  and capitate +
1-2 times number of carpels +
0.3 cm3 mm <br />0.003 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
? (?) +  and ? (?) +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
5-18-branched +
Malvastrum lindheimerianum +
Malvastrum coromandelianum +
Malvastrum +
species +
perennial +  and annual +
monoecious +, dioecious +  and hermaphroditic +