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water-hyssop

tropical water-hyssop

Habit Herbs, annual or perennial, emergent or submerged, sometimes rooting from proximal nodes. Perennials.
Stems

prostrate or erect, glabrous or slightly hairy.

prostrate, 8–14 cm, hairy.

Leaves

cauline, opposite [whorled];

petiole obscure or absent;

blade fleshy (B. monnieri) or not, not leathery, margins entire, crenate, or serrate.

hairy;

blade base ± truncate, margins entire, apex rounded.

Inflorescences

axillary, flowers solitary or in pairs;

bracts absent.

Pedicels

present or absent;

bracteoles present [absent].

6–10 mm.

Flowers

bisexual;

sepals 4 or 5, distinct, outer wider than inner, ovate, lanceolate, or oblong, calyx radially or bilaterally symmetric, campanulate;

corolla white (sometimes with yellow throat), pink, or violet-blue, radially or bilaterally (B. repens) symmetric, regular or weakly bilabiate, rotate or campanulate, rarely tubular, tube base not spurred or gibbous, throat not densely pilose internally, lobes 4 or 5, abaxial 2 or 3, adaxial 2;

stamens 2–4, adnate to corolla, didynamous or equal, filaments glabrous;

staminode 0;

ovary 2-locular, placentation axile;

stigmas peltately flattened and semicapitate.

sepals 5, ovate to oblong, calyx bilaterally symmetric;

corolla white with white throat, 2–5 mm;

stamens 2–4, equal.

Fruits

capsules, dehiscence septicidal-loculicidal or loculicidal.

Seeds

80–120, brownish black, ellipsoid to cylindric, reticulate, wings absent.

× = 14.

Bacopa

Bacopa innominata

Phenology Flowering Jun–Sep.
Habitat Marshy areas, alluvial deposits along streams, wet ditches, muddy shores and banks.
Elevation 0–200 m. (0–700 ft.)
Distribution
from USDA
North America; Mexico; Central America; South America; West Indies; s Europe; Asia; Africa; Indian Ocean Islands (Madagascar); Australia
[BONAP county map]
from FNA
FL; GA; MD; NC; SC; VA
[BONAP county map]
Discussion

Species ca. 70 (7 in the flora).

Bacopa laxiflora (Bentham) Wettstein ex Edwall, native to Central America and South America, has been introduced to Mexico and may be expected in the flora area. Plants of B. laxiflora resemble B. monnieri; they differ by erect stems and acute leaf blade apices.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Bacopa innominata differs from B. rotundifolia in having corollas entirely white; B. rotundifolia has corollas with yellow throats.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Key
1. Leaf blades 1-nerved.
B. monnieri
1. Leaf blades (3–)5–9+-nerved.
→ 2
2. Plants aromatic; bracteoles present; corollas violet-blue with violet-blue throats.
B. caroliniana
2. Plants not aromatic; bracteoles absent; corollas white with yellow or white throats or pink with pink throats.
→ 3
3. Leaf blade bases narrowly cuneate.
→ 4
4. Leaf blade margins crenate.
B. egensis
4. Leaf blade margins entire.
B. repens
3. Leaf blade bases broadly cuneate to truncate.
→ 5
5. Pedicels 6–10 mm; corollas 2–5 mm, white with white throats.
B. innominata
5. Pedicels 9–51 mm; corollas 5–14 mm, white with yellow throats.
→ 6
6. Pedicels 9–15 mm; corollas 5–10 mm.
B. rotundifolia
6. Pedicels 17–51 mm; corollas 10–14 mm.
B. eisenii
Source FNA vol. 17, p. 260. Author: Adjoa Richardson Ahedor. FNA vol. 17, p. 263.
Parent taxa Plantaginaceae Plantaginaceae > Bacopa
Sibling taxa
B. caroliniana, B. egensis, B. eisenii, B. monnieri, B. repens, B. rotundifolia
Subordinate taxa
B. caroliniana, B. egensis, B. eisenii, B. innominata, B. monnieri, B. repens, B. rotundifolia
Synonyms Conobea innominata, B. cyclophylla, B. stragula, Herpestis rotundifolia
Name authority Aublet: Hist. Pl. Guiane 1: 128, plate 49. (1775) — name conserved (M. Gómez) Alain: Revista Soc. Cub. Bot. 13: 61. (1957)
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