Ludwigia virgata

Michaux

Fl. Bor.-Amer. 1: 89. 1803.

Common names: Savannah primrose-willow
Synonyms: Isnardia virgata (Michaux) de Candolle
Treatment appears in FNA Volume 10.

Roots fascicled, often fusiform, or spreading horizontally. Stems subterete to scarcely angled, with narrow raised lines or wings decurrent from leaf-axils, 45–85 cm, branched mainly near base, glabrate with strigillose raised lines or strigillose. Leaves: stipules narrowly deltate, 0.1–0.2 × 0.1–0.15 mm; sessile; blade ovate to obovate proximally, lanceolate-linear to linear distally, 2–7 × 0.2–1 (–1.5) cm, base cuneate, margins entire, apex acute to rounded, surfaces strigillose, densely so particularly along veins; bracts usually very reduced in size, sub­linear. Inflorescences sparse racemes, flowers solitary in leaf-axils; bracteoles attached in subopposite pairs on distal 1/3 of pedicel, lanceolate-linear, 0.7–3.2 (–5) ×0.2–0.5 mm, margins entire, apex acute, surfaces strigillose. Flowers: sepals strongly reflexed, narrowly ovate-deltate, 6–10 × 2.5–4.5 mm, margins entire, apex acute, surfaces finely strigillose to glabrate; petals cor­date, 14–19 × 13–15 mm, base attenuate, apex emarginate; filaments opaque white, awl-shaped, 1.9–4.2 mm, anthers 2–4 × 0.6–1 mm; ovary subcuboid to globose, 3–4 × 3–4 mm; nectary disc elevated, domed, 0.8–1.4 mm diam., prominently 4-lobed, ringed with silky-curly hairs; style 5–9.5 mm, gla­brous, stigma capitate to hemispherical, 0.6–1.3 × 1.3–2.6 mm, shallowly 4-lobed, as long as or exserted beyond anthers. Capsules subglobose to ellipsoid, 3.5–6.8 × 3.3–4.3 mm, 4-angled, angles not developed into wings, pedicel 6.5–17 mm. Seeds light-brown, elliptic-oblong to reniform, 0.5–0.7 × 0.3–0.4 mm, surface cells elongate transversely to seed length or elongate parallel to length near raphe. 2n = 16.


Phenology: Flowering summer.
Habitat: Sandy savannas, pinelands, damp roadside ditches, margins of ponds, bogs, irrigated fields, usually within 75 miles of sea coast.
Elevation: 0–300 m.

Distribution

Ala., Fla., Ga., Miss., N.C., S.C., Va.

Discussion

Selected References

None.

Lower Taxa

None.
... more about "Ludwigia virgata"
not developed +
3(-5)-aperturate +
0.2 cm2 mm <br />0.002 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
0.06 cm0.6 mm <br />6.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
acute +  and rounded +
Peter C. Hoch +
Michaux +
attenuate +  and cuneate +
indehiscent +  and loculicidal +
1 cm10 mm <br />0.01 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
2 cm20 mm <br />0.02 m <br /> (7 cm70 mm <br />0.07 m <br />) +
lobed +, toothed +  and entire +
ovate +  and obovate proximally +
reduced +
0.2 cm2 mm <br />0.002 m <br /> (1 cm10 mm <br />0.01 m <br />) +
reduced +
0.32 cm3.2 mm <br />0.0032 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
dark red +  and black +
0.07 cm0.7 mm <br />7.0e-4 m <br /> (0.32 cm3.2 mm <br />0.0032 m <br />) +
lanceolate-linear +
0.02 cm0.2 mm <br />2.0e-4 m <br /> (0.05 cm0.5 mm <br />5.0e-4 m <br />) +
straight +  and slightly curved +
0.35 cm3.5 mm <br />0.0035 m <br /> (0.68 cm6.8 mm <br />0.0068 m <br />) +
spreading +  and erect +
4-angled +, subglobose +  and ellipsoid +
0.33 cm3.3 mm <br />0.0033 m <br /> (0.43 cm4.3 mm <br />0.0043 m <br />) +
Savannah primrose-willow +
Ala. +, Fla. +, Ga. +, Miss. +, N.C. +, S.C. +  and Va. +
0–300 m. +
basifixed +  and versatile +
awl--shaped +
0.19 cm1.9 mm <br />0.0019 m <br /> (0.42 cm4.2 mm <br />0.0042 m <br />) +
long-pedicellate +  and subsessile +
straight +  and slightly curved +
by a terminal pore +  and dehiscent +
spreading +  and erect +
cylindric +  and clavate turbinate obpyramidal or globose +
Sandy savannas, pinelands, damp roadside ditches, margins of ponds, bogs, irrigated fields, usually within 75 miles of sea coast. +
silky-curly +
perennial +
glandular-puberulent +, hirtellous +, villous +  and strigillose +
deciduous +
strigillose +
0.08 cm0.8 mm <br />8.0e-4 m <br /> (0.14 cm1.4 mm <br />0.0014 m <br />) +
4-lobed +  and domed +
0.3 cm3 mm <br />0.003 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
globose +
3mm +  and 4mm +
numerous +  and 1 +
subopposite +
submerged +
swollen +
0.65 cm6.5 mm <br />0.0065 m <br /> (1.7 cm17 mm <br />0.017 m <br />) +
14mm +  and 19mm +
5 +  and 4 +
1.3 cm13 mm <br />0.013 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
Flowering summer. +
Fl. Bor.-Amer. +
paired +, solitary +  and cluster +
ascending +, decumbent +  and erect +
inconspicuous +
elongate +
expanded +
fusiform +
basal +  and cauline +
clavate +  and globose +
light-brown +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.07 cm0.7 mm <br />7.0e-4 m <br />) +
50 +  and 400 +
pitted +  and smooth +
elliptic-oblong +  and reniform +
0.03 cm0.3 mm <br />3.0e-4 m <br /> (0.04 cm0.4 mm <br />4.0e-4 m <br />) +
flushed with red +, cream +  and yellow +
persistent +
post-anthesis +
5 +  and 4 +
ovate-deltate +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.45 cm4.5 mm <br />0.0045 m <br />) +
parenchymatous +
parietal +, axile +  and placentation +
2 +  and 1 +
unequal +  and subequal +
2 times as many as sepals +
aquatic +, amphibious +  and terrestrial +
2 times as many as sepals +
prostrate +  and decumbent +
strigillose +  and glabrate +
decurrent +, subterete +  and scarcely angled +
45 cm450 mm <br />0.45 m <br /> (85 cm850 mm <br />0.85 m <br />) +
0.06 cm0.6 mm <br />6.0e-4 m <br /> (0.13 cm1.3 mm <br />0.0013 m <br />) +
4-lobed +, capitate +  and hemispherical +
0.13 cm1.3 mm <br />0.0013 m <br /> (0.26 cm2.6 mm <br />0.0026 m <br />) +
sessile +  and petiolate +
green +  and dark reddish +
0.01 cm0.1 mm <br />1.0e-4 m <br /> (0.02 cm0.2 mm <br />2.0e-4 m <br />) +
intrapetiolar +
0.01 cm0.1 mm <br />1.0e-4 m <br /> (0.015 cm0.15 mm <br />1.5e-4 m <br />) +
0.5 cm5 mm <br />0.005 m <br /> (0.95 cm9.5 mm <br />0.0095 m <br />) +
aquatic +, amphibious +  and terrestrial +
finely strigillose +  and glabrate +
papillate +
Isnardia virgata +
Ludwigia virgata +
Ludwigia sect. Ludwigia +
species +
3(-5)-aperturate +