Ludwigia erecta |
Ludwigia linifolia |
|
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yerba de jicotea |
flaxleaf seedbox, southeastern primrose-willow |
|
Habit | Herbs annual, rarely persistent a second year from woody base. | Herbs slender, rarely with aerenchyma, forming slender stolons 4–15(–30) cm, 0.7–1(–1.5) mm thick. |
Stems | erect, 4-angled, rarely 4-winged, sometimes basally terete, 40–280 cm, simple to densely branched, branches often ascending, glabrous. |
erect or ascending, slightly ridged, usually well branched, 12–55(–62) cm, glabrous. |
Leaves | stipules deltate, 0.2–0.3 × 0.15–0.2 mm; petiole 0.2–2.2 cm, somewhat flattened and continuous with ridges or wings on stem; blade elliptic to narrowly lanceolate, 2–20 × 0.2–4 cm, base cuneate, margins minutely scabrid, apex acute or acuminate, membranous, surfaces glabrous or sometimes minutely strigillose along abaxial veins; bracts often reduced. |
alternate; stipules narrowly ovate to narrowly lanceolate, 0.2–0.3 × 0.1–0.2 mm; stolons: petiole narrowly attenuate, 0.05–0.5 cm, blade narrowly obovate or oblanceolate to spatulate, 0.5–2 × 0.1–0.6 cm; stems: sessile, blade linear to linear-oblanceolate, 1.5–4 × 0.1–0.4(–0.6) cm, base very narrowly cuneate, margins entire with obscure hydathodal glands, apex acuminate to acute; bracts linear, reduced. |
Inflorescences | leafy spikes, flowers solitary in distal axils; bracteoles attached at base of ovary or on lower 1/2, without subtending glands, deltate, 0.3–0.5 × 0.2–0.3 mm, apex acute. |
leafy spikes, flowers solitary in leaf axils; bracteoles attached 0–1.5 mm distal to base of ovary, very narrowly oblanceolate to linear, (1.5–)2.5–9(–13) × 0.2–0.8 mm, margins entire, apex acute. |
Flowers | sepals ovate or lanceolate, 3–6 × 1–2 mm, apex acute or short-acuminate, surfaces usually glabrous, sometimes strigillose; petals obovate, 3.5–5 × 2–2.5 mm; stamens 8 in 2 subequal series, filaments 1.3–1.5 mm, anthers oblong, 0.6–1 × 0.4–0.5 mm; ovary obconic, 4-angled, 4–10 × 2–4 mm, usually glabrous, rarely strigillose; nectary disc plane on ovary apex, 3–4 mm diam., 4-lobed, glabrate; style 0.5–1.5 × 0.5–0.6 mm, stigma globose, 0.8–1 × 1–1.2 mm, not exserted beyond anthers and pollen shed directly on it. |
sepals ascending, green, narrowly lanceolate-deltate, (3–)4–7 × 1.1–1.7 mm, margins entire, apex narrowly acute, surfaces glabrous or minutely papillose; petals narrowly obovate-elliptic, 4–6 × 2–4 mm, base obtuse, apex obtuse or rounded; filaments pale yellow, (1.3–)1.5–2.5(–3) mm, anthers oblong, 0.6–1.1 × 0.5–0.8 mm; pollen shed in tetrads; ovary subcylindric, 3–4 × 1–1.5 mm; nectary disc elevated 0.3–0.7 mm on ovary apex, bright yellow, 0.8–1.5 mm diam., prominently 4-lobed, minutely papillose; style yellow, 1.25–2.5 mm, glabrous, stigma subcapitate, 0.3–0.6 × 0.6–0.8 mm, shallowly 4-lobed, not exserted beyond anthers. |
Capsules | oblong-linear to squarish-cylindric, 4-angled, 10–22 × 2–4 mm, thin-walled, irregularly dehiscent, subsessile. |
subcylindric, terete or slightly angled, 5–10(–12) ×1.3–2(–2.2) mm, hard-walled, irregularly dehiscent, pedicel 0 mm. |
Seeds | elongate-ovoid, 0.3–0.5 × 0.2–0.3 mm, raphevery reduced and inconspicuous. |
reddish brown, oblong-elliptic, 0.6–0.7 × 0.2–0.3 mm, surface cells nearly isodiametric. |
2n | = 16. |
= 16. |
Ludwigia erecta |
Ludwigia linifolia |
|
Phenology | Flowering summer–early fall. | Flowering late Jun–Oct. |
Habitat | Pond margins and depressions, wet sand ditches and prairies. | Drainage ditches, margins of creeks or swamps, open edges of cypress swamps, moist pinelands, edges of brackish lakes. |
Elevation | 0–100[–300] m. (0–300[–1000] ft.) | 0–300 m. (0–1000 ft.) |
Distribution |
AL; AZ; FL; Central America; South America; Mexico (Campeche, Chiapas, Jalisco, Michoacán, Nayarit, Oaxaca, Tabasco); West Indies; Africa (Nigeria, Tanzania); Indian Ocean Islands (Comoros Islands, Madagascar, Seychelles) |
AL; FL; GA; MS; NC; SC; Mexico (Tabasco) |
Discussion | Ludwigia erecta, which is morphologically similar to L. decurrens and often growing with it, is modally self-pollinating and is usually easy to distinguish from that species. Although Ludwigia erecta is widely distributed in warm temperate regions in the New World and Africa, it appears to be most closely related to species restricted to South America. Its appearance in a rather remote locality in Arizona in 2006 may be attributable to transport there in mud on migrating birds. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Ludwigia linifolia is primarily a coastal species that extends farther inland in Georgia and the Carolinas. Being one of five diploids in sect. Isnardia, it has particularly prominent nectary lobes and appears to be modally outcrossing (C. I. Peng 1989). It also is known from a disjunct population on the Yucatán Peninsula in Tabasco, Mexico. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 10. | FNA vol. 10. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | Jussiaea erecta, Isnardia discolor, J. acuminata, J. acuminata var. latifolia, J. acuminata var. longifolia, J. altissima, J. declinata, J. erecta var. plumeriana, J. erecta var. sebana, J. onagra, J. plumeriana, J. ramosa, L. acuminata | Isnardia linifolia |
Name authority | (Linnaeus) H. Hara: J. Jap. Bot. 28: 292. (1953) | Poiret in J. Lamarck et al.: Encycl., Suppl. 3: 513. (1814) |
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