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Hygrophila polysperma

Species category

Weed

Common name

Indian swampweed

Diagnostic characters

Planting unit

True seedTrue seed:
A mature fertilized ovule consisting of an embryo, with or without and external food reserve (e.g., endosperm) enclosed by the testa.

Shape

Compressed ovalOval:
Broadly elliptic.

Size

  • Length 0.5–0.8 mm
  • Width 0.4–0.6 mm
  • Thickness 0.1–0.2 mm

Color

Brown

Texture

Rough

Other structures

HilumHilum:
The scar on the seed coat at the place of its detachment from the seed stalk (funiculus).
 is ovalOval:
Broadly elliptic.
 and on the margin.

Identification notes

Surface texture may be considered to be finely stippled.

Noxious weed seed categories

State Noxious Weed: California 
Federal

Learn more on ITP's Federal Noxious Weed Disseminules tool.

AOSA examination list

Not included

Nomenclature

Family

Acanthaceae

Valid name

Hygrophila polysperma (Roxb.) T. Anderson

Hygrophila polysperma. Seed capsules. Photo by Julia Scher, USDA-APHIS-PPQ.
Hygrophila polysperma. Seed capsules. Photo by Julia Scher, USDA-APHIS-PPQ.
Hygrophila polysperma. Seeds with a finely stippled surface texture. Photo by Julia Scher, USDA-APHIS-PPQ.
Hygrophila polysperma. Seeds with a finely stippled surface texture. Photo by Julia Scher, USDA-APHIS-PPQ.
Hygrophila polysperma. Seeds with an oval hilum on the margin. Photo by Julia Scher, USDA-APHIS-PPQ.
Hygrophila polysperma. Seeds with an oval hilum on the margin. Photo by Julia Scher, USDA-APHIS-PPQ.