Najas indica Cham.

Naïade des Indes (fr)

Species

Angiosperms > Alismatales > Hydrocharitaceae > Najas

Characteristics

Up to c. 40 cm, lower internodes 2-10 cm by (0.6-)0.75-l.2(-l.7) mm. Leaves (1¼-)2½-4.5(-6) cm by (0.3-)0.8-1.2(-1.6) mm, flat tosubterete or triangular in section, apex acute to obtuse (blade c. 3 mm below the tip 0.2-0.4(-0.5) mm wide); margin on either side with (1-)5-30(-40) conspicuous spiny teeth, sometimes up to the lower 15 mm of the blade unarmed; dorsal surface sometimes with 1-10(-30) spines; spine-cells 0.1-0.25 mm, all (dark) brown; teeth up to as long as half (in the upper part of the blade as long as) the width of the blade; midrib 0.12-0.1 times as wide as the blade; cavities occupying half or almost the entire width of the blade, often with distinct septa. Sheath (2-)2.5-4(-5) by (1.5-)2-4(-6)mm, on either side with (2-)5-12(-20) spines, but unarmed on the inner edge of the auricles; auricles absent to (long-, especially in Indian specimens) triangular, truncate to rounded or almost acute, rarely falcate, (0.1-)0.3-0.6(-1) by (0.3-)0.5-l (-1.5) mm, mostly entire, sometimes toothed or lobed, seldom lacerate up to halfway. Flowers mostly solitary. Male flowers: spathe 2.2-3.6 mm, neck mostly cylindrical, 0.3-1 mm, tip almost truncate to very oblique, entire to up to halfway lacerate; anther subsessile, 4-celled, about elliptical to oblong, (1.2-)1.5-2.2(-2.5) by 0.7-1.2 mm; 'perianth' lobes mostly distinct, (±) nipple-shaped. 'Pedicel' c. 0.2 mm, in anthesis 2.7-3.5 mm. Female flowers: spathe absent (except in some Indian specimens), (1.7-)2-3(-3.4) mm; ovary (0.6-)0.7-0.9(-1.2) by (0.25-)0.3-0.4(-0.45) mm, style (0.4-)0.5-0.8(-1.2) mm, with 2(-1) stigmas (0.4-)0.8-1.6(-1.8) mm. Seeds (1.5-)1.7-2.3 by 0.75-0.9 mm; testa with (14-)16-20(-25) length-rows of (17-)22-25(-30) subquadrate or 5-6-angular areoles, which are mostly slightly wider than long.
Life form annual
Growth form herb
Growth support aquatic
Foliage retention -
Sexuality monoecy
Pollination -
Spread -
Mature width (meter) -
Mature height (meter) 0.1 - 0.2
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Rooting depth (meter) -
Root diameter (meter) -
Flower color
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Fruiting months
JanFebMar
AprMayJun
JulAugSep
OctNovDec
Nitrogen fixer -
Photosynthetic pathway -

Environment

Found in a great variety of habitats, in various biotopes of freshwater, mostly shallow but up to 5 m depth, and c. 1000 m altitude, also found in brackish water of fish-ponds near Djakarta with a salinity of up to 30°/00 ( SUNIER Treubia 2 1922 190-195 ), both in everwet regions and in those subject to a dry season. One of the commonest species in Malaysia.
Light -
Soil humidity 10-12
Soil texture -
Soil acidity -
Soil nutriment -
Hardiness (USDA) 8-12

Usage

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

Cultivation

Mode -
Germination duration (days) -
Germination temperacture (C°) -
Germination luminosity -
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Optimum temperature (C°) -
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Productivity -

Images

Najas indica unspecified picture

Distribution

Najas indica world distribution map, present in Andorra, Australia, Bangladesh, China, Indonesia, India, Japan, Myanmar, Malaysia, Pakistan, Philippines, Thailand, Taiwan, Province of China, Viet Nam, and South Africa

Conservation status

Najas indica threat status: Least Concern

Identifiers

LSID urn:lsid:ipni.org:names:603020-1
WFO ID wfo-0000769512
COL ID 45KZL
BDTFX ID 119661
INPN ID 717324
Wikipedia (EN) Link
Wikipedia (FR)

Synonyms

Caulinia alternifolia Fluvialis indica Najas kingii Najas lacerata Caulinia foveolata Caulinia indica Najas falciculata Najas indica Najas lobata Najas palustris Najas foveolata Najas foveolata Najas foveolata var. minor Najas minor var. indica