The Nonindigenous Occurrences section of the NAS species profiles has a new structure. The section is now dynamically updated from the NAS database to ensure that it contains the most current and accurate information. Occurrences are summarized in Table 1, alphabetically by state, with years of earliest and most recent observations, and the tally and names of drainages where the species was observed. The table contains hyperlinks to collections tables of specimens based on the states, years, and drainages selected. References to specimens that were not obtained through sighting reports and personal communications are found through the hyperlink in the Table 1 caption or through the individual specimens linked in the collections tables.

Mytella charruana
Mytella charruana
(Charru mussel)

Copyright Info
Mytella charruana (d'Orbigny, 1846)

Common name: Charru mussel

Synonyms and Other Names: M. falcata, M. strigata, M. arciformis

Size: 25 mm

Native Range: Coast of South America.

Hydrologic Unit Codes (HUCs) Explained
Interactive maps: Point Distribution Maps

Nonindigenous Occurrences:

Table 1. States with nonindigenous occurrences, the earliest and latest observations in each state, and the tally and names of HUCs with observations†. Names and dates are hyperlinked to their relevant specimen records. The list of references for all nonindigenous occurrences of Mytella charruana are found here.

StateFirst ObservedLast ObservedTotal HUCs with observations†HUCs with observations†
FL198620153Cape Canaveral; Florida Southeast Coast; Lower St. Johns
GA200620061Ogeechee Coastal
SC200820163Bulls Bay; Salkehatchie; St. Helena Island

Table last updated 8/12/2022

† Populations may not be currently present.

Means of Introduction: Unknown. Probable ballast water introduction.

Status: The mussel has disappeared from the Jacksonville area. No new sightings have been reported there since 1986.  However, it appears that a new population may be established in the Mosquito Lagoon area of east-central Florida where juvenile mussels were collected in 2004.

Impact of Introduction: This species created a biofouling problem at the Jacksonville Electric Authority's Northside Generating Station by clogging an intake pipe filter just feet away from steam condensers.  The mussels in Mosquito Lagoon were collected off a reef where they could compete with native organisms for food and habitat.

References: (click for full references)

Keen, A.M. 1971. Sea shells of tropical west America. Second edition. Stanford University Press, California, 1064 p.

Author: Benson, A.J.

Revision Date: 10/21/2004

Citation Information:
Benson, A.J., 2022, Mytella charruana (d'Orbigny, 1846): U.S. Geological Survey, Nonindigenous Aquatic Species Database, Gainesville, FL, https://nas.er.usgs.gov/queries/FactSheet.aspx?SpeciesID=106, Revision Date: 10/21/2004, Access Date: 8/12/2022

This information is preliminary or provisional and is subject to revision. It is being provided to meet the need for timely best science. The information has not received final approval by the U.S. Geological Survey (USGS) and is provided on the condition that neither the USGS nor the U.S. Government shall be held liable for any damages resulting from the authorized or unauthorized use of the information.


The data represented on this site vary in accuracy, scale, completeness, extent of coverage and origin. It is the user's responsibility to use these data consistent with their intended purpose and within stated limitations. We highly recommend reviewing metadata files prior to interpreting these data.

Citation information: U.S. Geological Survey. [2022]. Nonindigenous Aquatic Species Database. Gainesville, Florida. Accessed [8/12/2022].

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