Flora of Northern Ireland : Ceratophyllum demersum

Ceratophyllum demersum L.

Rigid Hornwort

Ceratophyllum demersum

Description: The commoner of the two hornworts in Northern Ireland. A submerged aquatic plant of lakes and drains, unevenly distributed about the Province, with one particular stonghold in Co. Down.

All names: Ceratophyllum demersum L.

Ceratophyllum demersum : Interactive Map

Distribution Map from NBN: Ceratophyllum demersum at National Biodiversity Network mapping facility, data for UK.

iNaturalist: Ceratophyllum demersum at iNaturalist World Species Observations database.

Hackney, P., 2026. Ceratophyllum demersum. L.. [In] Flora of Northern Ireland.
https://habitas.org/flora/species.php?item=2761. Accessed on 2026-11-02.