Ludwigia glandulosa |
Ludwigia grandiflora |
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creeping seedbox, cylindricfruit primrose-willow |
large-flower primrose-willow, Uruguayan primrose-willow |
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Habit | Herbs slender, forming stolons 5–20 cm, 0.4–0.8 mm thick. | Herbs, subshrubs, or emergent aquatics, rooting at lower nodes, sometimes woody at base, white pneumatophores 8–10 cm often on submerged stems. | ||||
Stems | erect, slightly ridged, usually well branched, 10–80(–100) cm, glabrate or often with strigillose raised lines decurrent from leaf axils. |
erect or ascending to creeping or floating, terete or sometimes angled distally, 20–300(–450) cm, usually densely branched, sometimes simple, glabrous if floating, or densely villous and viscid throughout, or rarely just on inflorescence. |
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Leaves | alternate; stipules ovate-triangular, 0.15–0.35 × 0.05–0.25 mm, succulent; stolons: petiole attenuate, 0.3–1 cm, blade narrowly elliptic, 1.5–3.5(–5.5) × 0.5–1.3(–2) cm; main stem: petiole 0–1.5 cm, blade usually narrowly elliptic to elliptic, sometimes linear, 3–12 × 0.3–2.1 cm, base attenuate, margins subentire with hydathodal glands often visible, apex acute to very narrowly acute, surfaces densely papillose-strigillose, abaxial veins glabrous or sparingly, minutely strigillose; leaves on side branches usually reduced, 0.8–4.5 ×0.2–1 cm; bracts much reduced. |
stipules (rarely in clusters of 3), ovate-deltate, 0.6–2 × 0.6–1.5 mm, fleshy, apex subacute, often mucronate; petiole 0.1–1.1 cm; blade usually lanceolate to (narrowly) elliptic or oblanceolate, rarely narrowly obovate, (1.7–)3.1–8(–10.5) × 0.5–2(–2.5) cm, chartaceous, viscid, base cuneate or attenuate, margins entire, apex obtuse or acute, always glandular-mucronate, surfaces densely villous, sometimes less dense adaxially, distal leaves more pubescent than proximal ones; bracts scarcely reduced. |
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Inflorescences | open, leafy racemes or spikes, flowers solitary in axils, often congested, especially on branches; bracteoles attached on pedicel at base of ovary or to 2 mm distal to base, narrowly lanceolate to sublinear, 0.4–1 × 0.1–0.4 mm, apex acuminate, surfaces glabrate. |
on emergent stems sometimes in leafy racemes, flowers solitary in leaf axils; bracteoles narrowly to broadly obovate, 1–1.2 × 0.7–0.8 mm, succulent, apex acute, oppositely attached at ovary base. |
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Flowers | sepals ascending, light green, ovate-deltate, 1.1–2.3 × 1–1.8 mm, margins entire, fringed with minute, strigillose hairs, apex short-acuminate or acute, surfaces glabrous; petals 0; filaments nearly translucent, 0.6–1.1 mm, anthers 0.3–0.5 × 0.3–0.6 mm; pollen shed in tetrads; ovary subcylindric, 2–5 × 0.8–1.9 mm; nectary disc elevated 0.3–0.4 mm on ovary apex, light green, 0.6–1.8 mm diam., 4-lobed, glabrous or minutely papillose; style pale green, 0.3–0.8 mm, glabrous, stigma broadly clavate to subglobose, 0.2–0.5 × 0.2–0.5 mm, not exserted beyond anthers. |
sepals usually deciduous, not persistent on capsule, lanceolate, 6–12(–16) × 2–4 mm, chartaceous, apex acute, surfaces densely villous; petals yellow, fan-shaped, (12–)16–20(–26) × 11–16(–21) mm, apex rounded, usually emarginate, rarely mucronate; stamens 10(or 12), in 2 unequal series, yellow, filaments reflexed, shorter ones (2.8–)3.8–5.3 mm, longer ones (3.7–)6–6.5 mm, anthers oblong, 1–2.5 × (0.6–)0.8–1.2 mm; ovary subcylindric, terete, 6–12 × 1.5–2.5 mm, apex thickened, densely villous; nectary disc slightly raised on ovary apex, yellow, 1.5–2.5 mm diam., lobed, ringed with villous hairs; style yellow, 4.7–6.7(–8) mm, glabrous or sparsely pubescent near base, stigma subcapitate-globose, 1–1.3 × 1.6–2.5 mm, usually exserted beyond anthers. |
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Capsules | subcylindric, subterete to obscurely 4-angled with 4 shallow grooves, 2–8(–9) × 1.3–2(–3) mm, hard-walled, irregularly dehiscent, pedicel 0–0.3(–0.5) mm. |
subcylindric, terete, straight or curved, (11–)14–25 × 3–4 mm, with thick woody walls, irregularly and tardily dehiscent, villous-viscid, pedicel 13–25(–27) mm. |
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Seeds | light brown, kidney-shaped with slightly pointed ends, 0.5–0.8 × 0.3–0.4 mm, surface cells columnar, elongate either parallel or transversely to seed length. |
embedded in wedge-shaped piece of endocarp, 0.8–1 × 0.8–0.9 mm. |
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2n | = 32. |
= 48. |
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Ludwigia glandulosa |
Ludwigia grandiflora |
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Phenology | Flowering summer. | |||||
Habitat | Wet places, along slow-moving rivers, streams, canals, ditches, often growing into main channel as aquatic weed. | |||||
Elevation | 0–200[–1200] m. (0–700[–3900] ft.) | |||||
Distribution |
c United States; e United States
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AL; AR; CA; FL; GA; KY; LA; MO; MS; NC; NJ; NY; OK; OR; PA; SC; TN; TX; VA; WA; WV; Central America (Guatemala); South America (Argentina, Bolivia, Brazil, Paraguay, Uruguay)
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Discussion | Subspecies 2 (2 in the flora). Ludwigia glandulosa consists of two subspecies: subsp. glandulosa is very common and widespread throughout the Atlantic and Gulf coastal plains and the Mississippi Embayment, westward to eastern Texas and southeastern Oklahoma; subsp. brachycarpa grows only in the western portion of the range of subsp. glandulosa, extending farther west in Texas and Oklahoma. The two taxa grow in similar habitats, but subsp. glandulosa prefers drier habitats farther south and west. The general distinctiveness of these subspecies is probably maintained by their modal autogamy; vegetative reproduction by means of stolons may likewise play a role in preserving favored genotypes (C. I. Peng 1989). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Ludwigia grandiflora occurs in two disjunct areas: the southeastern United States on the coastal plain of southern South Carolina, Georgia, northern Florida, Louisiana, west to central Texas, and recently in southern California (P. C. Hoch and B. J. Grewell 2012) and Oregon; and central South America from south of the Amazon basin of Brazil and Bolivia where it is very scattered, to Uruguay, northeastern Argentina, and Paraguay where it is very frequent. It has been collected three times in Guatemala and twice in Missouri, although it is not clearly established in either region. It usually grows below 200 m elevation, but in Guatemala and in Santa Catarina, Brazil (Smith & , MO), it has been collected as high as Klein 133831200 m elevation. Populations of L. grandiflora in the United States are fairly variable, although not as much as in South American populations. As noted by Greuter and Burdet, the publication of Jussiaea grandiflora Ruíz & Pavon, which was a synonym of J. peruviana, occurred in 1830, not in 1802 as reported (P. A. Munz 1942; P. H. Raven 1963[1964]). Therefore, J. grandiflora Michaux in 1803 is legitimate, and J. grandiflora Ruíz & Pavon is an illegitimate homonym. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Key |
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Source | FNA vol. 10. | FNA vol. 10. | ||||
Parent taxa | ||||||
Sibling taxa | ||||||
Subordinate taxa | ||||||
Synonyms | Jussiaea grandiflora, J. repens var. grandiflora, J. repens var. hispida, J. stenophylla, J. stuckertii, J. uruguayensis, L. clavellina var. grandiflora, L. uruguayensis | |||||
Name authority | Walter: Fl. Carol., 88. (1788) | (Michaux) Greuter & Burdet: Willdenowia 16: 448. (1987) | ||||
Web links |