Callitriche obtusangula

Tracheophyta MagnoliopsidaCallitrichaceaeCallitricheCallitriche obtusangula


A perennial herb typical of permanent, still or slow-flowing mesotrophic to eutrophic waters, extending into brackish water in coastal grazing marshes. It also grows in a terrestrial form on wet mud as water levels drop. Lowland.



World Distribution

Suboceanic Southern-temperate element.

© S. Hammonds

Broad Habitats

Light (Ellenberg): 7

Moisture (Ellenberg): 11

Reaction (Ellenberg): 7

Nitrogen (Ellenberg): 6


Salt Tolerance (Ellenberg): 1

January Mean Temperature (Celsius): 4.1

July Mean Temperature (Celsius): 15.7

Annual Precipitation (mm): 840

Length: 60

Perennation - primary


Life Form - primary

Perennial hydrophyte (perennial water plant)



Clonality - primary

Irregularly fragmenting (mainly water plants)

Distribution information

Count of 10km squares in Great Britain: 757

Count of 10km squares in Ireland: 157

Count of 10km squares in the Channel Isles: 4

Atlas Change Index: 1.35

Weighted Changed Factor: -42

Weighted Change Factor Confidence (90%)


Distribution information

JNCC Designations


PLANTATT - Attributes of British and Irish plants. (.zip 1455KB) This dataset was compiled and published in 2004, and last updated in November 2008. Download includes an Excel spreadsheet of the attributes, and a PDF explaining the background and nomenclature. Note that the PDF version is the booklet as published, whereas the Excel spreadsheet incorporates subsequent corrections. A hardcopy can be purchased from the Centre for Ecology and Hydrology.

Atlas text references

Atlas (151a)
Meusel H, Jäger E, Rauschert S, Weinert E
1978.  Vergleichende Chorologie der zentraleuropäischen Flora. Volume 2. 2 vols.
Preston CD, Croft JM
1997.  Aquatic plants in Britain and Ireland.
Schotsman HD
1967.  Les Callitriches: espèces de France et taxa nouveaux d'Europe.