Water Fern (Azolla filiculoides) - Detail

Species Detail - Water Fern (Azolla filiculoides) - Species information displayed is based on the dataset "National Invasive Species Database".

Terrestrial Map - 10km

Distribution of the number of records recorded within each 10km grid square (ITM).

Live Map

Marine Map - 50km

Distribution of the number of records recorded within each 50km grid square (WGS84).

Live Map

Species image

Scientific Name Azolla filiculoides

Common Name Water Fern

Taxon Version Key NBNSYS0000002090 RecommendedWell-formed

Synonyms Azolla caroliniana Willd., Azolla filiculoides var. filiculoides , Azolla pinnata auct., non R. Br.

Designations Invasive Species: Regulation S.I. 477/2011 (Ireland) || Invasive Species: Detailed Risk Assesment || Invasive Species: Medium Risk Invasive Species (2013 Report) || Invasive Species: Regulation S.I. 374/2024 (Ireland) || Invasive Species: The Wildlife (Northern Ireland) Order 1985 || Invasive Species: Detailed Risk Assesment >> Moderate Risk

Abbreviation azfil

Authority Lam.

Group Fern

Rank Species

Number Of Records 136

Number Of 10Km Squares 55

Number Of 50Km Squares 34

Oldest Record 01/01/1893

Newest Record 20/05/2025

Phenology - earliest record (across all datasets) 1 January (recorded in 2008)

Phenology - latest record (across all datasets) 31 December (recorded in 2021)

Species Profiles

Citation Collated by the National Biodiversity Data Centre from different sources, National Invasive Species Database, National Biodiversity Data Centre, Ireland, Water Fern (Azolla filiculoides), accessed 31 August 2025, <https://maps.biodiversityireland.ie/Dataset/397/Species/127372>

Species Detail - Water Fern (Azolla filiculoides) - Species information displayed is based on the dataset "National Invasive Species Database".

Terrestrial Map - 10km

Marine Map - 50km

Species image

Records per month (across all datasets)

Records per year (across all datasets)