Amaranthus floridanus

(S. Watson) J. D. Sauer

Madroño 13: 25. 1955.

Common names: Florida water-hemp Florida amaranth
IllustratedEndemic
Basionym: Acnida floridana S. Watson Proc. Amer. Acad. Arts 17: 376. 1882
Treatment appears in FNA Volume 4. Treatment on page 417. Mentioned on page 412, 416.

Stems erect, branched, slender, usually (0.5–) 1–1.5 m. Leaves: petiole 1/4 length of blade; blade linear to narrowly oblong, usually 10 (–20) × 1 cm, base narrowly cuneate, margins entire, plane, apex obtuse to rounded. Inflorescences terminal, linear spikes to panicles. Bracts: of pistillate flowers 1–1.5 mm; of staminate flowers with moderately heavy midrib, 1–1.5 mm. Pistillate flowers: tepals 1–2 (–3), unequal, inner tepals lanceolate to narrowly lanceolate, 1–1.5 mm, apex acute to acuminate; style-branches spreading; stigmas 3. Staminate flowers: tepals 5, with excurrent midrib, equal to subequal, 2 (–2.5) mm, apex acute to indistinctly mucronulate in outer tepals; stamens 5. Utricles reddish to reddish-brown, occasionally with indistinct longitudinal ridges, subglobose to broadly obovoid, 1.5–2.5 mm, wall thin or slightly fleshy, irregularly rugose. Seeds dark reddish-brown to dark-brown, 0.7–1 mm diam., shiny.


Phenology: Flowering late spring–fall.
Habitat: Coastal dunes, beaches, swamps, marshes, disturbed habitats, such as gardens and fields near coast
Elevation: 0-10 m

Discussion

Selected References

None.

Lower Taxa

None.
... more about "Amaranthus floridanus"
Sergei L. Mosyakin +  and Kenneth R. Robertson +
(S. Watson) J. D. Sauer +
cuneate +
Acnida floridana +
10 cm100 mm <br />0.1 m <br /> (20 cm200 mm <br />0.2 m <br />) +
10 cm100 mm <br />0.1 m <br /> (?) +
linear +  and narrowly oblong +
elliptic to subulate-linear +  and elliptic +
persistent +
triangular +, deltate +, subulate +, linear +, lanceolate +  and ovate +
Florida water-hemp +  and Florida amaranth +
0-10 m +
peripheral +
staminate +  and pistillate +
not enfolding +
minute +  and small +
not +  and dehiscent +
Coastal dunes, beaches, swamps, marshes, disturbed habitats, such as gardens and fields near coast +
terminal +  and axillary +
lanceolate;narrowly lanceolate +
0.1 cm1 mm <br />0.001 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
reduced +
scarious +  and membranaceous +
well-developed +
1/4 length of blade +
Flowering late spring–fall. +
rudimentary +
0.07 cm0.7 mm <br />7.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
lenticular +  and subglobose +
Illustrated +  and Endemic +
well-developed +
prostrate +  and decumbent +
slender +
100 cm1,000 mm <br />1 m <br /> (150 cm1,500 mm <br />1.5 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 />) +
Acnida sect. Acnidastrum +  and Acnida sect. Montelia +
Amaranthus floridanus +
Amaranthus sect. Acnida +
species +
0.2 cm2 mm <br />0.002 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
distinct +
linear-lanceolate +  and reduced-linear +
subequal +  and unequal +
2 cm20 mm <br />0.02 m <br /> (?) +
indurate +, membranaceous +, chartaceous +  and scarious +
walled +  and 3(-5)-veined +
reddish +  and reddish-brown +
tuberculate +  and rugose +
subglobose +  and broadly obovoid +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
membranaceous +