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anglestem primrose-willow, anglestem waterprimrose

Mexican primrose-willow

Habit Herbs, perennial or (robust) annual, or shrubs, often with woody base, when aquatic, forming white pneumatophores from nodes. Herbs (robust)or shrubs, herbs tap-rooted, often woody at base, with peeling bark.
Stems

usually erect or strongly ascending, rarely floating or creeping, terete to somewhat angled on young branches, 30–250 cm, well branched to sparsely branched or simple, usually villous, often also strigillose, rarely glabrous, with raised lines decurrent from leaf axils.

erect to spreading, terete or sometimes ridged, 60–250(–400) cm, densely branched, densely villous to glabrate, especially near base.

Leaves

stipules narrowly deltate, 0.1–0.2 × 0.1–0.2 mm;

petiole 0.2–3.5 cm;

blade broadly lanceolate, 3.5–18 × 1–4 cm, base narrowly cuneate, margins subentire, apex acuminate, surfaces hirsute or villous;

bracts slightly to much 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 axils;

bracteoles often absent, when present, narrowly deltate, 2–3 × 1.2–2.4 mm, attached near ovary base.

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-deltate, 5.5–11 × 1.5–3 mm, margins entire, apex acuminate, surfaces villous;

petals orange-yellow, obovate, 5–11 × 4–8 mm;

stamens (8 or)10 or 12(or 14), in 2 unequal series, longer filaments 2.5–4.5 mm, shorter ones 1.5–2.5 mm, anthers oblong, 1.2–1.6 × 0.7–1 mm, extrorse;

ovary cylindric, subterete, 10–16 × 2–3 mm, glabrate to strigillose or villous;

nectary disc slightly elevated at ovary apex, 2–4 mm diam., lobed, depressed, surrounded by densely matted white hairs;

style 3–4.5 mm, glabrous, stigma capitate-globose, 1–1.5 × 2–2.5 mm, ± exserted beyond anthers.

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

obscurely [4 or]5 or 6[or 7]-angled or subterete, straight or curved, 15–50 × 2.5–4 mm, relatively thin-walled, seeds visible as bumps, tardily and irregularly loculicidal, villous, pedicel 2–20 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

in 1 row per locule, horizontal and loosely embedded in an easily detached horseshoe-shaped segment of firm endocarp, pale brown, obovoid, 1–1.2 mm, shiny, finely pitted, raphe much narrower than seed body.

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

= 32, 48.

= [16], 32, 48.

Ludwigia leptocarpa

Ludwigia octovalvis

Phenology Flowering summer. Flowering summer–early fall.
Habitat Wet places, mainly along coastal areas, especially ditches, banks near brackish water. Wet or moist places, along coasts, streams, ditches, swamps, often near disturbance or cultivation.
Elevation 0–200[–1300] m. (0–700[–4300] ft.) 0–300[–2200] m. (0–1000[–7200] ft.)
Distribution
from FNA
AL; AR; DE; FL; GA; IL; IN; KY; LA; MD; MO; MS; NC; OH; OK; PA; SC; TN; TX; VA; WV; Central America; South America; Mexico (Campeche, Chiapas, Jalisco, Nayarit, Oaxaca, San Luis Potosí, Tabasco, Tamaulipas, Veracruz); West Indies (Cuba, Hispaniola, Jamaica, Puerto Rico); Africa; Indian Ocean Islands (Madagascar)
[WildflowerSearch map]
[BONAP county map]
from FNA
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)
[WildflowerSearch map]
[BONAP county map]
Discussion

Ludwigia leptocarpa is a globally widespread and morphologically variable species; in the flora area it is distributed widely in wet areas of the southeastern United States. Both tetraploid and hexaploid plants are known, but it is not clear if or how ploidy level is related to the considerable morphological variation, especially in pubescence type and pattern.

(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. Seminudae Onagraceae > subfam. Ludwigioideae > Ludwigia > sect. Macrocarpon
Sibling taxa
L. alata, L. alternifolia, L. arcuata, L. bonariensis, L. brevipes, L. curtissii, L. decurrens, L. erecta, L. glandulosa, L. grandiflora, L. hexapetala, L. hirtella, L. lanceolata, L. linearis, L. linifolia, L. maritima, L. microcarpa, L. octovalvis, L. palustris, L. peploides, L. peruviana, L. pilosa, L. polycarpa, L. ravenii, L. repens, L. simpsonii, L. spathulata, L. sphaerocarpa, L. suffruticosa, L. virgata
L. alata, L. alternifolia, L. arcuata, L. bonariensis, L. brevipes, L. curtissii, L. decurrens, L. erecta, L. glandulosa, L. grandiflora, L. hexapetala, L. hirtella, L. lanceolata, L. leptocarpa, L. linearis, L. linifolia, L. maritima, L. microcarpa, L. palustris, L. peploides, L. peruviana, L. pilosa, L. polycarpa, L. ravenii, L. repens, L. simpsonii, L. spathulata, L. sphaerocarpa, L. suffruticosa, L. virgata
Synonyms Jussiaea leptocarpa, J. biacuminata, J. foliosa, J. leptocarpa subsp. angustissima, J. leptocarpa var. angustissima, J. leptocarpa var. meyeriana, J. pilosa, J. pilosa var. robustior, J. schottii, J. surinamensis, J. variabilis, J. variabilis var. meyeriana, J. variabilis var. pilosa, L. leptocarpa var. angustissima, L. leptocarpa var. meyeriana 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 (Nuttall) H. Hara: J. Jap. Bot. 28: 292. (1953) (Jacquin) P. H. Raven: Kew Bull. 15: 476. (1962)
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