Wolffia brasiliensis
Watermeal

Key Characteristics

Floating aquatic water-meal of shallow lakes; plants without roots; leaves boat-shaped, tiny (<1mm), the surface covered with tiny raised dots.

Status and Rank

  • State Status: T
  • State Rank: S1
  • Global Rank: G5

Occurrences

County NameNumber of OccurrencesYear Last Observed
Berrien32015
Distribution map for Wolffia brasiliensis

Updated 7/21/2017. Information is summarized from MNFI's database of rare species and community occurrences. Data may not reflect true distribution since much of the state has not been thoroughly surveyed.

Habitat

This tiny aquatic plant is known from a single site in Berrien County, where it was found in a buttonbush swamp. It is likely overlooked due to its small size.

Natural Community Types

Methodology

For each species, lists of natural communities were derived from review of the nearly 6,500 element occurrences in the MNFI database, in addition to herbarium label data for some taxa. In most cases, at least one specimen record exists for each listed natural community. For certain taxa, especially poorly collected or extirpated species of prairie and savanna habitats, natural community lists were derived from inferences from collection sites and habitat preferences in immediately adjacent states (particularly Indiana and Illinois). Natural communities are not listed for those species documented only from altered or ruderal habitats in Michigan, especially for taxa that occur in a variety of habitats outside of the state.

Natural communities are not listed in order of frequency of occurrence, but are rather derived from the full set of natural communities, organized by Ecological Group. In many cases, the general habitat descriptions should provide greater clarity and direction to the surveyor. In future versions of the Rare Species Explorer, we hope to incorporate natural community fidelity ranks for each taxon.

Associated Plants

No associates have been recorded for Michigan other than buttonbush.

Management

This species is likely to benefit from protection of hydrology. In addition, the only known population should be monitored and status surveys conducted for additional occurrences in southwest Michigan.

General Survey Guidelines

Random meander search covers areas that appear likely to have rare taxa, based on habitat and the judgement of the investigator.

Survey Methods

Page Citation

Michigan Natural Features Inventory. 2007. Rare Species Explorer (Web Application). Available online at http://mnfi.anr.msu.edu/explorer [Accessed Dec 18, 2017]

More Information

See MNFI Species Abstract

References

Survey References

Technical References

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