Elatine ambigua Wight

Asian waterwort (en), Élatine (fr)

Species

Angiosperms > Malpighiales > Elatinaceae > Elatine

Characteristics

Usually small and inconspicuous, annual or short-lived perennial. Stems: in water spreading, internodes up to 2 cm long, with branches up to 10 cm or more long; on land all parts smaller, creeping and rooting at nodes, densely branched and turf-forming, internodes (1.5-)3-4(-11) mm long, ± 0.5 mm in diameter. Leaves glabrous, lanceolate to elongate-lanceolate (sometimes with petiole-like bases when growing in water), (3-)4-6(-15) mm long, (0.5-)1-1.5(-3) mm wide, margins not toothed, tip rounded. Flowers solitary in leaf axils, distinctly pedicellate; pedicels 1-2 mm long, with 2 membranous bracteoles at the base; bracteoles minute, irregularly toothed or beard-like. Sepals 3, united below, without distinct veins, not glandular, ovate, ± 0.5 mm long, tips obtuse. Petals 3, ovate to elongate ovate, ± 1 mm long, reddish-white, spreading at anthesis but lying on the fruit later. Stamens 3, shorter than the sepals. Styles 3, curved. Capsules ± spherical, ± 1.5 mm in diameter, when ripe lying to the side of and not in the leaf axil, opening by 3 valves. Seeds ± 0.5 mm long, ± 0.1 mm in diameter, slightly curved or almost straight, with a net-like pattern on the surface, the individual pits mostly hexagonal.
More
Plants 1.5-3 cm tall. Stem richly branched. Leaves subsessile or shortly petiolate; stipules lanceolate, ca. 1 mm, membranous, margin dentate, apex acute; petiole (if present) ca. 1 mm; leaf blade spatulate, lanceolate to ovate-lanceolate, or elliptic, 2-5 × ca. 0.7 mm, margin entire, apex subacute. Flowers axillary, solitary; pedicel conspicuous, curved downward at fruiting stage, 1.5-2.5 mm. Calyx 3-fid; lobes oblong-ovate or broadly lanceolate, ca. 0.5 × 0.3 mm, apex obtuse. Petals 3, reddish, long elliptic, elliptic, or ovate, 1-1.5 × ca. 0.5 mm, 2-3 × as long as sepals. Stamens 3, shorter than petals. Ovary obovoid, 3-loculed; styles 3. Capsule cylindric-ovoid, 3-septicidal. Seeds nearly straight or slightly curved, ca. 0.5 mm, reticulate-striate.
Herbs, submersed, 1.5–4(–8) cm. Stems prostrate or erect, branched. Leaves green; stipules lanceolate, 1 mm, margins dentate, apex acute; petiole 0.1–1 mm; blade lanceolate or oblong-elliptic, 2–6 × 0.5–1.5 mm, base cuneate, apex obtuse to acute. Pedicels 0.5–2.5 mm, recurved in fruit. Flowers: sepals 3, equal, oblong-ovate or broadly lanceolate, 0.5 × 0.3 mm; petals 0 or 3, reddish, long-elliptic or ovate, 1–1.5 × 0.5 mm; stamens 3; styles 3. Capsules oblong-ovoid, 3-locular, 1 mm diam. Seeds 10 per locule, narrowly oblong, straight or curved 15–30°, 0.3 × 0.1 mm; pits obscure, round, length 1–4 times width, in 6 rows, 19–25(–30) per row.
A tender, creeping herb very similar to E. triandra but the petioles sometimes reach 2 mm. long and the slender pedicels occasionally reach 5 mm. long in fruit. In floral structure the two species are remarkably alike.
Leaves 2½-5 mm long. Pedicels distinct, ½-1½ mm. Stamens shorter than the sepals. Otherwise quite like E. triandra and probably only a temporarily terrestrial form of it.
Life form annual
Growth form herb
Growth support free-standing
Foliage retention deciduous
Sexuality hermaphrodite
Pollination -
Spread -
Mature width (meter) -
Mature height (meter) 0.02 - 0.04
Root system creeping-root
Rooting depth (meter) -
Root diameter (meter) -
Flower color
Blooming months -
Fruit color -
Fruiting months -
Nitrogen fixer -
Photosynthetic pathway -

Environment

Light -
Soil humidity 9-12
Soil texture -
Soil acidity -
Soil nutriment -
Hardiness (USDA) 8-12

Usage

Uses -
Edible -
Therapeutic use -
Human toxicity -
Animal toxicity -

Cultivation

Mode -
Germination duration (days) -
Germination temperacture (C°) -
Germination luminosity -
Germination treatment -
Minimum temperature (C°) -
Optimum temperature (C°) -
Size -
Vigor -
Productivity -

Distribution

Elatine ambigua world distribution map, present in American Samoa, Bangladesh, Bulgaria, Bhutan, Botswana, China, France, Hong Kong, Indonesia, India, Liberia, Malaysia, Namibia, Korea (Democratic People's Republic of), Romania, Thailand, Ukraine, United States of America, Viet Nam, and South Africa

Conservation status

Elatine ambigua threat status: Least Concern

Identifiers

LSID urn:lsid:ipni.org:names:324664-1
WFO ID wfo-0000665297
COL ID 395CL
BDTFX ID 84133
INPN ID -
Wikipedia (EN)
Wikipedia (FR)

Synonyms

Potamopitys ambigua Elatine ambigua Elatine triandra var. pedicellata