Ludwigia peruviana |
Ludwigia octovalvis |
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Peruvian primrose-willow |
Mexican primrose-willow |
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Habit | Herbs often woody at base, with peeling bark. | Herbs (robust)or shrubs, herbs tap-rooted, often woody at base, with peeling bark. |
Stems | usually ridged, rarely succulent, profusely branched, 100–400 cm, usually villous, rarely glabrous, hairs deciduous in age, multicellular, usually tawny. |
erect to spreading, terete or sometimes ridged, 60–250(–400) cm, densely branched, densely villous to glabrate, especially near base. |
Leaves | stipules deciduous, narrowly deltate, 1–1.5 × 0.3–0.5 mm, setaceous; petiole 0–1.5 cm; blade usually lanceolate, elliptic or broadly elliptic, sometimes ovate, obovate, or rounded, 2–45 × 1–10 cm, base obtuse or cuneate, rarely asymmetrical, margins entire or gland-toothed, apex usually acute or acuminate, rarely rounded and emarginate, mostly scabrid, membranous or papery, surfaces usually villous, sometimes glabrous; bracts usually not strongly reduced. |
stipules deltate, 0.5–0.8 × 0.6–0.7 mm, fleshy; petiole 0–1 cm; blade linear to oblong or oblanceolate, sometimes narrowly ovate, 0.7–14.5 × 0.1–4 cm, base tapered, margins entire, apex acute to acuminate, surfaces ± densely villous or strigillose; bracts not or scarcely reduced. |
Inflorescences | leafy racemes, flowers solitary in distal axils; bracteoles deciduous, usually attached near base or on lower 1/2 of ovary, sometimes on upper pedicel, subtended by reduced, glandlike stipels, ovate or lanceolate to linear, 5–20 × 1–6 mm, apex acute or short-acuminate, surfaces villous. |
open, leafy racemes, flowers solitary in axils, presentation often radial; bracteoles ovate, 3–8 × 1.4–4 mm, apex acuminate, attached near base of ovary. |
Flowers | sepals ovate or ovate-lanceolate, 10–23 × 4–9 mm, apex acute or short-acuminate, sometimes glandular-serrulate; petals bright yellow, orbiculate or obovate, 10–40 × 10–40 mm, apex rarely emarginate, short-clawed; stamens 8(or 10) in 2 unequal series, yellow, shorter filaments 1.5–4 mm, longer ones 3.5–5 mm, anthers oblong, 3–6 mm; ovary obconic, 4- or 5-angled, sometimes subterete, 5–20 × 3–7 mm, narrowed to pedicel, usually densely villous, sometimes glabrous; nectary disc elevated 0.3–3.2 mm on ovary apex, 4–6 mm diam., 4(or 5)-lobed, sunken, ringed by long, white hairs; style 1.5–3.5 mm, stigma globose, 1.6–3.5 × 1.8–3.5 mm, usually as long as stamens, rarely exserted beyond them. |
sepals lanceolate to ovate, (6–)8–13 × 3–7 mm, apex acuminate, surfaces strigillose adaxially; petals bright yellow, fan-shaped, (5–)10–20 × 5–20 mm, apex sometimes shallowly notched; stamens 8 in 2 subequal series, yellowish white, filaments spreading, 4–6 mm, anthers oblong, 2.5–5 × 1–2 mm; pollen shed in tetrads or sometimes polyads; ovary cylindric, 4-angled, sometimes slightly twisted, 8–22 × 1–3 mm; nectary disc elevated 0.4–0.5 mm on ovary apex, 1–2.4 mm diam., with 4 white-pubescent sunken lobes opposite petals; style 2.5–3.5 mm, stigma capitate-globose, 1.8–3.5 × 2.5–3.5 mm, surrounded by anthers and pollen shed directly on it. |
Capsules | ± sharply 4- or 5-angled, 10–40 × 6–13 mm, thin-walled, irregularly dehiscent, pedicel 5–65 mm. |
cylindric to clavate-cylindric, subterete to ± 4-angled, 17–50 × 2.5–8 mm, thin-walled, irregularly dehiscent by 4–8 linear valves splitting from apex, short-villous, pedicel 5–25 mm. |
Seeds | brown or reddish brown, oblong, 0.6–0.9 × 0.3–0.4 mm, rounded at ends, with inconspicuous raphe. |
in several indistinct rows per locule, broad-cylindric with rounded ends, 0.6–0.9 × 0.5–0.8 mm, raphe inflated and nearly equal to seed body. |
2n | = 64, 80, 96, 128. |
= [16], 32, 48. |
Ludwigia peruviana |
Ludwigia octovalvis |
|
Phenology | Flowering Jun–Aug(–Sep) (sometimes in any month). | Flowering summer–early fall. |
Habitat | Wet places, ditches, drainage canals, sloughs, swales, marshy shores, wet clearings. | Wet or moist places, along coasts, streams, ditches, swamps, often near disturbance or cultivation. |
Elevation | 0–200[–2600] m. (0–700[–8500] ft.) | 0–300[–2200] m. (0–1000[–7200] ft.) |
Distribution |
AL; FL; GA; NC; TX; Central America; South America; Mexico (Chiapas, Durango, Oaxaca, Puebla, Tabasco, Veracruz); West Indies [Introduced in Eurasia (India, Indonesia, Singapore, Sri Lanka), Australia]
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AL; FL; GA; LA; MS; NC; SC; TX; Mexico; Central America; South America; West Indies; s Asia; e Asia (Burma, China, India, Japan, Thailand, Vietnam); Africa; Indian Ocean Islands (Comoros Islands, Madagascar); Pacific Islands (New Caledonia, Papua New Guinea, Philippines)
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Discussion | Ludwigia peruviana is sometimes cultivated and naturalized, which may account for occurrences in North America and Eurasia. Except in the Amazon basin, where it is known only from few collections in western Amazonia, and in northeastern Brazil, where it is scarce, L. peruviana is common throughout its range, and may behave as a weed, especially along slow-flowing canals and drainage ditches. Ludwigia peruviana is also naturalized at scattered localities in Asia (P. H. Raven 1963[1964]) and around Sydney, Australia. The earliest collection from Asia is labeled “ex horto bot. Bogoriensi Javae misit 1869” (Raven). It also occurs locally in the Nilgiri Mountains of southwest India and in Sri Lanka, as well as in scattered locations in Bangka, Java, Malaysia, and Sumatra from sea level to 1000 m (Raven 1963[1964], 1978). Jussiaea grandiflora Ruíz & Pavon, a synonym for J. peruviana Linnaeus, appeared in 1830, not in 1802 (P. A. Munz 1942; P. H. Raven 1963[1964]); it is a later homonym of J. grandiflora Michaux (1803), as reported in W. Greuter and T. Raus (1987). Jussiaea hirta (Linnaeus) Swartz is an illegitimate homonym and J. hirta (Linnaeus) Vahl is an illegitimate isonym; both pertain here. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Ludwigia octovalvis is perhaps the most widespread species of Ludwigia worldwide and exhibits a very complex pattern of morphological and ecological variation, correlated only in part with multiple ploidy levels; this complexity is reflected in its extensive synonymy. P. H. Raven (1963[1964]), P. A. Munz (1942, 1965), and others have proposed formal classifications to account for this variation, with mixed results and additional study using more powerful analytical tools is clearly needed in order to develop a more stable classification. In the absence of better understanding, and despite some correlated patterns of morphological and geographical variation on a global scale, this treatment does not recognize infraspecific taxa. Jussiaea hirsuta Velloso, J. suffruticosa var. angustifolia Chodat & Hassler, J. velutina Kunze, and Ludwigia suffruticosa (Linnaeus) M. Gómez are later homonyms; these four names pertain here. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 10. | FNA vol. 10. |
Parent taxa | Onagraceae > subfam. Ludwigioideae > Ludwigia > sect. Myrtocarpus | Onagraceae > subfam. Ludwigioideae > Ludwigia > sect. Macrocarpon |
Sibling taxa | ||
Synonyms | Jussiaea peruviana, J. hirsuta, J. macrocarpa, J. mollis, J. peruviana var. glaberrima, J. speciosa, J. sprengeri, L. hirta, Oenothera hirta | Oenothera octovalvis, Jussiaea calycina, J. clavata, J. frutescens, J. haenkeana, J. hirta, J. ligustrifolia, J. occidentalis, J. octofila, J. octonervia, J. octonervia var. sessiliflora, J. octovalvis, J. parviflora, J. peruviana var. octofila, J. pubescens, J. sagrana, J. salicifolia, J. scabra, J. suffruticosa, J. suffruticosa var. ligustrifolia, J. suffruticosa var. linearifolia, J. suffruticosa var. octofila, J. suffruticosa subsp. octonervia, J. suffruticosa var. octonervia, J. suffruticosa var. sessiliflora, J. suffruticosa var. sintenisii, J. venosa, J. villosa, L. octovalvis var. ligustrifolia, L. octovalvis var. octofila, L. octovalvis subsp. sessiliflora, L. octovalvis var. sessiliflora, L. pubescens, L. pubescens var. ligustrifolia, L. pubescens var. linearifolia, L. pubescens var. sessiliflora, L. sagrana |
Name authority | (Linnaeus) H. Hara: J. Jap. Bot. 28: 293. (1953) | (Jacquin) P. H. Raven: Kew Bull. 15: 476. (1962) |
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