Plant · GBIF taxon 2650107
Pacific Mosquitofern
Azolla filiculoidesAlso known as Water Fern, Pacific Azolla, Large Mosquito Fern, Fairy Moss
Pacific mosquitoferns form dense floating mats on calm freshwaters, shifting from vibrant green to vivid ruby red when exposed to intense sunlight or cool temperatures. A symbiotic cyanobacterium hosted within leaf cavities fixes atmospheric nitrogen, allowing the fern to multiply rapidly and cover entire ponds in days. This rapid growth suppresses mosquito breeding by blocking access to the water surface, giving the plant its common name.
AquaticFloatingNitrogen-Fixing
—observations
—countries
—peak records
Least ConcernConservation statusIUCN Red List categoriesLCNTVUENCREWEXLeast ConcernRed List categories, explained →
Diet & prey
- Sunlight
- Dissolved phosphates
- Atmospheric nitrogen
Predators
- Waterfowl
- Aquatic snails
- Azolla weevil
ThreatsDredging, aquatic herbicides, and extreme winter cold
HabitatsPonds, ditches, quiet river backwaters, and wetlands
Life spanPerennial in mild climates; annual in severe freeze zones
Size / weightNot available
Classification
- FamilySalviniaceae
- SpeciesAzolla filiculoides
Range data is not available yet.
Interaction riskLow
- Low
- Moderate
- High
- Very high
- Why interaction risk is low
- Safe to observe at a normal distance.
Responsible observation
- Sunlight Identification: Look for deep red coloration in autumn or full sun, contrasting with shaded green patches.
- Prevent Spread: Avoid moving water or plants between ponds to prevent spreading dense floating mats to new waterways.
Frequent Companion no rights reserved, uploaded by Philipp · cc0
Symbiont Close Relative Close Relative 
Family Member (c) Игорь Васильев, some rights reserved (CC BY) · cc-by
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