Vascular Plants of North Carolina
Account for Valdivia Duckweed - Lemna valdiviana   Philippi
Members of Lemna with account distribution info or public map:
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Section 5 » Order Arales » Family Araceae
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DistributionUnlike the other native Lemna species on the NC list, L. valdiviana has no taxonomic issues (and no obvious identification issues) and thus the range map below accurately represents the collection records in the SERNEC database. As with several other duckweeds, it is limited in NC to the Coastal Plain and the lower Piedmont only. Of course, because all duckweeds are tiny and easily overlooked or passed over for collecting, it is expected to occur in a great majority of Coastal Plain counties in reality.

This is a wide-ranging species, ranging from NH and OR south to southern FL and the MX border.
AbundanceWeakley's (2018) map indicates it is "common" in the NC Coastal Plain but "rare" in the Piedmont. The NHP's state rank of S3 probably underestimates the abundance of the species in the state; S4 seems to be better, especially as it is presumed that many or most biologists do not bother to make collections of duckweeds (owing to difficulty of handling such tiny plants).
HabitatThe habitats are essentially identical to other duckweeds -- still or slowly moving waters of ponds, pools, lakes, and swamps.
See also Habitat Account for General Herbaceous Ponds
PhenologyFlowers seldom.
IdentificationLemna species are tiny floating plants with flattened leaf-like stems (fronds) that produce roots under the stem (i.e., under the water surface). These species have just one root per frond. This is the only Lemna species in the state with just one nerve on a frond; others have 3-5 such nerves. In addition, the frond color is usually a pale green, whereas most other species have bright green fronds; however, this likely is not a fail-safe character, as some fronds or populations may have bright green fronds.
Taxonomic CommentsNone

The range maps for this and other duckweeds (Lemna spp.) are likely to be very incomplete, owing to recent changes in nomenclature; not to mention being in a group of plants often overlooked or not often collected by biologists because of their tiny size and aquatic/floating habits.
Other Common Name(s)Pale Duckweed
State RankS3 [S4]
Global RankG5
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