Contains 25 accepted taxa overall.
Characteristics
Classification
Citation
LUDWIGIA Linnaeus, Sp. Pl. 188. 1753 (Ludvigia); corr. Linnaeus, Gen. Pl., ed. 5. 55. 1754.
-
TYPE: Ludwigia alternifolia Linnaeus Lectotypified by Britton & A. Brown, Ill. Fl. N. U.S., ed. 2. 2: 586. 1913.

Species
Scientific Name | Common Name | Herbarium Specimens | Status | Photos |
---|---|---|---|---|
Ludwigia alata | Winged Seedbox | |||
Ludwigia alternifolia | Alternate-leaf Seedbox | |||
Ludwigia arcuata | Piedmont Primrose-willow | |||
Ludwigia bonariensis | Carolina primrose-willow | |||
Ludwigia brevipes | Long Beach Seedbox, Coastal Plain Water-purslane | |||
Ludwigia decurrens | Wingstem Water-primrose | |||
Ludwigia glandulosa | Small-flowered Seedbox | |||
Ludwigia grandiflora | Showy Water-primrose | |||
Ludwigia hexapetala | Common Water-primrose | |||
Ludwigia hirtella | Rafinesque's Seedbox | |||
Ludwigia lanceolata | Lanceleaf Seedbox | |||
Ludwigia leptocarpa | Water-willow | |||
Ludwigia linifolia | Flaxleaf Seedbox | |||
Ludwigia maritima | Harper's Seedbox | |||
Ludwigia microcarpa | Small-fruited Seedbox | |||
Ludwigia octovalvis | Mexican primrose-willow | |||
Ludwigia palustris | Common Water-purslane | |||
Ludwigia peploides var. glabrescens | Floating Primrose-willow | |||
Ludwigia pilosa | Hairy Seedbox | |||
Ludwigia ravenii | Raven's Seedbox | |||
Ludwigia repens | Creeping Seedbox | |||
Ludwigia spathulata | Southern Water-purslane | |||
Ludwigia sphaerocarpa | Globe-fruited Seedbox | |||
Ludwigia suffruticosa | Shrubby Seedbox | |||
Ludwigia virgata | Savanna Seedbox |
Identification Key
1. Leaves opposite
1. Leaves alternate
2
2. Stamens 4-5 per flower, as many as the sepals
2. Stamens 8-10 per flower, twice the number of sepals
3
3. Sepals 5(-7)
3. Sepals 4
1. (Key A) Pedicels 6-45 mm long
2
1. Pedicels 0-2(-5) mm long
3
2. Pedicel mostly subequal to shorter than the subtending leaf; petals 4-5 mm long
2. Pedicel usually much longer than the subtending leaf; petals 7-11 mm long
3. Plant densely strigulose
3. Plant glabrate
4
4. Sepals 1-2.1 mm long; petals absent; anthers 0.2-0.4 mm long, the pollen shed as monads; faces of fruit with a longitudinal band or obscure line running down from the sepal midrib, the appearing dissimilar from the corners
4. Sepals 1.8-5 mm long; petals present but often quickly deciduous; anthers 0.4-0.9 mm long, the pollen sheds as tetrads; fruit faces and corners similar in appearance
1. (Key B) Fruit much longer than wide
2
1. Fruit about as long as wide
4
2. Leaf blades elliptic, lanceolate, ovate, to oblanceolate, larger ones 4-12 mm wide; petals absent; fruit with a groove descending from the middle of the calyx lobe
2. Leaf blades linear to linear-oblanceolate, larger ones 1-4 mm wide; petals present; fruit without a groove
3
3. Calyx lobes 2-3 mm long, much shorter than the quadrangular fruit
3. Calyx lobes 5-6 mm long, ca. 0.6-1 times longer than the subcylindric fruit
4. Pedicel apparent, 3-20 mm long
5
4. Pedicel scarcely evident, 0-2 mm long
8
5. Leaf blade base cuneate-attenuate
5. Leaf blade base rounded to obtuse
6
6. Proximal leaf blades glabrous; style 7-10 mm long, longer than the sepals
6. Proximal leaf blades pubescent; styles to 3 mm long, shorter than the sepals
7
7. Plant hirsute
7. Plant pubescent to puberulent
8. Flowers several in a densely congested in a terminal spike with bract-like leaves
8. Flowers mostly separated along a leafy racemes or interrupted spike, or few in a congested, bracteate terminal spike
9
9. Plant hirtellous
10
9. Plant glabrous to strigillose
11
10. Sepals whitish along the upper surface and often tinged pink along the midvein and edge, the apex long-acuminate to subcuspidate and reflexed; anther 0.6-1.3 mm long, filament 0.7-1.1 mm long; style glabrous, 0.25-0.5 mm long; nectary disc hirtellous between the lobes
10. Sepals greenish on the upper surface, the apex acuminate and ascending; anther ca. 0.3 mm long, filament 1.5-2.5 mm long; style hirtellous, 1-2 mm long; nectary disc glabrous
11. Capsule quadrangular or winged
12
11. Capsule not angular, not winged
13
12. Stem usually ridged or winged; sepals whitish and subequal to the fruit
12. Stems usually smooth to obscurely ridged; sepals greenish, ca. ½ as long as the fruit
13. Sepals 1-2 mm long; fruit 1-1.5 mm long; seeds reddish brown
13. Sepals 2-4 mm long; fruit 1.5-7 mm long; seeds tan to yellowish
14
14. Leaf blades obovate, spatulate, to oblanceolate
14. Leaf blades linear-lanceolate to oblong-elliptic
1. (Key C) Stems prostrate to decumbent, rooting
2
1. Stems erect to ascending, not rooting at least distally
3
2. Bracteoles below hypanthium lanceolate; hypanthium subequal to shorter than the sepals
2. Bracteoles below hypanthium deltoid to ovate; hypanthium longer than the sepals
3. Fruit cylindric, 3-5 cm long (much longer than the pedicel), 2-4 mm wide
3. Fruit obconic, quadrangular, 1-3 cm long (subequal to the pedicel), 5-10 mm wide
1. (Key D) Stem conspicuously 4-winged
2
1. Stem without wings or slightly ridged on the angles
3
2. Leaf blades lanceolate, ovate-lanceolate, to elliptic
2. Leaf blades linear-lanceolate
3. Stems hirsute to villous
4
3. Stems glabrate
5
4. Fruit more than twice as long as the sepals, with a distinct ridge descending from the sepal midvein
4. Fruit subequal to slightly longer than the sepals, without a ridge continuous with the sepal midvein
5. Calyx lobes 3-4 mm long; petals 4-5 mm long
5. Calyx lobes (5-)10-15 mm long; petals (10-)15-30 mm long
6
6. Pedicel shorter than the hypanthium; hypanthium subequal to slightly longer than the sepals
6. Pedicel longer than the hypanthium; hypanthium more than twice as long as the sepals
Genus Synonyms
Synonym | Full Citation | Basionym | Type |
---|---|---|---|
No synonyms found. |