Azolla caroliniana Willd.
Carolina mosquito fern
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New England Distribution
Adapted from BONAP data
Non-native: introduced (intentionally or unintentionally); has become naturalized.
County documented: documented to exist in the county by evidence (herbarium specimen, photograph). Also covers those considered historical (not seen in 20 years).
State documented: never been documented from the county, but known from the state. May be present. Or, may be restricted to a small area or a habitat (alpine, marsh, etc.), so unlikely found in some counties.
Note: when native and non-native populations both exist in a county, only native status is shown on the map.
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The aquatic fern, Carolina mosquito fern, is native to North American, but it is an uncommon visitor to New England, having been collected in Connecticut and Massachusetts. This tiny, mat-forming plant has been extensively used in wastewater treatment and water pollution mitigation for its ability to absorb heavy metals and radioactivity.
Lacustrine (in lakes or ponds), riverine (in rivers or streams), swamps
- New England state
- Features of leaves
- there are no special features on the leaves
- New England state
- Specific habitat
- in lakes or ponds
- in rivers or streams
Occurs only in wetlands. (Wetland indicator code: OBL)
New England Distribution and Conservation Status
- New Hampshire
- Rhode Island
Exact status definitions can vary from state to state. For details, please check with your state.
- not applicable (S-rank: SNA)
Native to North America?
Yes and no (some introduced)
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Information from Dichotomous Key of Flora Novae Angliae
1. Azolla caroliniana Willd. E
Carolina mosquito fern. CT, MA; also reported from NH by Magee and Ahles (1999), but voucher specimens are unknown. Still or slow-moving water of lakes, pools, swamps, and streams. Reports of this species from RI were based on a collection taken from a pond on the University of Rhode Island campus— Champlin 51 (Champlin Herb.).