Amaranthus crassipes

Schlechtendal

Linnaea 6: 757. 1831.

Common names: Clubfoot amaranth spreading amaranth tropical spreading amaranth
Illustrated
Synonyms: Amaranthus crassipes var. warnockii (I. M. Joh nston) Henrickson Amaranthus warnockii
Treatment appears in FNA Volume 4. Mentioned on page 432.

Plants annual, glabrous. Stems prostrate or weakly ascending, erect when young, branched mostly from base, 0.1–0.6 m. Leaves: petiole nearly 1/2 as long as blade; blade broadly elliptic, obovate, orbiculate, or oblanceolate, (0.5–) 1–3 (–4.5) × 0.3–2 (–2.5) cm, base cuneate, margins entire, plane to undulate, apex broadly rounded or emarginate. Inflorescences axillary clusters borne from base to apex, axes much thickened, appearing inflated, becoming indurate at maturity (only in A. scleropoides and A. crassipes). Bracts of pistillate flowers keeled (only A. scleropoides and A. crassipes have keeled bracts), deltate, 0.5–0.9 mm. Pistillate flowers: tepals (4–) 5, narrowly spatulate, clawed, with small expanded blade, equal or subequal, 2–3 mm, apex rounded and apiculate; claws becoming indurate and scarious at maturity; style-branches spreading; stigmas usually 2 (–3), almost sessile. Staminate flowers intermixed with pistillate; tepals 5, membranaceous; stamens 3 (–5). Utricles obovoid to compressed-obovoid, 1.4–2 mm, shorter than tepals, prominently muricate (especially in distal 1/2), indehiscent. Seeds dark brownish or reddish black to black, compressed-ovoid to broadly lenticular, 1–1.4 mm diam., shiny.


Phenology: Flowering summer and fall.
Habitat: Open, seasonally wet flats, shores of water bodies, waste places, other disturbed habitats
Elevation: 0-1300 m

Distribution

Ala., Ariz., Fla., La., N.Mex., S.C., Tex., ne Mexico, West Indies, n South America, occasionally in other regions

Discussion

Two varieties have been distinguished by J. Henrickson (1999) within Amaranthus crassipes: var. crassipes with leaf blades nearly orbiculate to ovate (obovate) and conspicuous veins on the green to yellow-green abaxial leaf surface; and var. warnockii (I. M. Johnston) Henrickson (= A. warnockii I. M. Johnston) with narrower oblanceolate grayish leaves with less distinct venation on the abaxial leaf surfaces. In Henrickson’s treatment, var. crassipes occurs mostly in the coastal areas (and is also reported for Arizona), while var. warnockii is reported from inland southwestern Texas and the Chihuahuan Desert region (Mexico: Coahuila, Chihuahua). We have not seen material of the new varieties and cannot evaluate their validity.

Selected References

None.

Lower Taxa

None.
... more about "Amaranthus crassipes"
Sergei L. Mosyakin +  and Kenneth R. Robertson +
Schlechtendal +
inflated +
indurate +
cuneate +
Undefined subg. Albersia +
3 cm30 mm <br />0.03 m <br /> (4.5 cm45 mm <br />0.045 m <br />) +
2 cm20 mm <br />0.02 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
1 cm10 mm <br />0.01 m <br /> (3 cm30 mm <br />0.03 m <br />) +
oblanceolate +, orbiculate +, obovate +  and elliptic +
expanded +  and small +
0.3cm;2cm +
persistent +
deltate +  and keeled +
scarious +  and indurate +
Clubfoot amaranth +, spreading amaranth +  and tropical spreading amaranth +
Ala. +, Ariz. +, Fla. +, La. +, N.Mex. +, S.C. +, Tex. +, ne Mexico +, West Indies +, n South America +  and occasionally in other regions +
0-1300 m +
peripheral +
staminate +  and pistillate +
hypogynous +
minute +  and small +
not +  and dehiscent +
Open, seasonally wet flats, shores of water bodies, waste places, other disturbed habitats +
reduced +
plane +  and undulate +
scarious +  and membranaceous +
Flowering summer and fall. +
rudimentary +
0.1 cm1 mm <br />0.001 m <br /> (0.14 cm1.4 mm <br />0.0014 m <br />) +
compressed-ovoid +  and broadly lenticular +
Illustrated +
prostrate +  and decumbent +
erect +, ascending +  and prostrate +
10 cm100 mm <br />0.1 m <br /> (60 cm600 mm <br />0.6 m <br />) +
not fleshy +
slender +
0.01 cm0.1 mm <br />1.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
Amaranthus crassipes var. warnockii +  and Amaranthus warnockii +
Amaranthus crassipes +
Amaranthus subg. Albersia +
species +
distinct +
clawed +  and spatulate +
subequal +
0.2 cm2 mm <br />0.002 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
membranaceous +
walled +  and 3(-5)-veined +
obovoid +  and compressed-obovoid +
0.14 cm1.4 mm <br />0.0014 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
membranaceous +