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.

Platichthys flesus
Platichthys flesus
(European flounder)
Marine Fishes

Copyright Info
Platichthys flesus (Linnaeus, 1758)

Common name: European flounder

Taxonomy: available through www.itis.govITIS logo

Identification: Wheeler (1969); Maitland (1977); Wheeler (1978).

Size: 50 cm.

Native Range: Marine; can penetrate freshwater. This species is native to the northeast Atlantic Ocean, Mediterranean Sea, and the Black Sea (Robins et al. 1991b).

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 Platichthys flesus are found here.

StateFirst ObservedLast ObservedTotal HUCs with observations†HUCs with observations†
MI198120004Keweenaw Peninsula; Lake Michigan; Lake St. Clair; Lake Superior
OH198419841Lake Erie
WI200020182Lake Michigan; Lake Superior

Table last updated 5/25/2024

† Populations may not be currently present.

Ecology: Primarily inhabits sandy or muddy areas in nearshore coastal and estuarine habitats. Feeds primarily on amphipods, copepods, ostracods, mysids, polychates, crustaceans, bivalves, and small fishes (Summers 1979; Aarnio et al. 1996).

Means of Introduction: Possibly introduced in ballast water from trans-Atlantic vessels (Emery and Teleki 1978; Crossman 1984).

Status: Reported from the Great Lakes near Ohio and Michigan.

Impact of Introduction: Unknown. The stomach contents of one of the specimens taken from Lake Erie included shells of a freshwater clam (Pisidium sp.) (Emery and Teleki 1978).

Remarks: European flounder do not reproduce in freshwater; therefore, they are not expected to become established in the Great Lakes. The majority of known specimens caught in North America all were taken in Canadian waters (Emery and Teleki 1978: Crossman 1984). Courtenay et al. (1991) included this species in their list of fishes introduced into the continental United States and Canada, but not known to be established. Their list also indicated that European flounder had been collected in Michigan and Ohio as well as to Ontario. It is assumed that Courtenay et al. (1991) included Ohio and Michigan because fish introduced into the Great Lakes do not respect political boundaries. Voucher specimens: Lake Erie (ROM 30521).

References: (click for full references)

Aarnio, K., E. Bonsdorff, and N. Rosenback. 1996. Food and feeding habits of juvenile flounder Platichthys flesus (L.), and turbot Scophthalmus maximus L. in the Åland archipelago, northern Baltic Sea. Journal of Sea Research 36:311-320.

Courtenay, W. R., Jr., D. P. Jennings, and J. D. Williams. 1991. Appendix 2: exotic fishes. Pages 97-107 in Robins, C. R., R. M. Bailey, C. E. Bond, J. R. Brooker, E. A. Lachner, R. N. Lea, and W. B. Scott. Common and scientific names of fishes from the United States and Canada, 5th edition. American Fisheries Society Special Publication 20. American Fisheries Society, Bethesda, MD.

Crossman, E. J. 1984. Introductions of Exotic Fishes into Canada. Pages 78-101 in W. R. Courtenay, Jr., and J. R. Stauffer, Jr., editors. Distribution, Biology, and Management of Exotic Fishes. Johns Hopkins University Press, Baltimore, MD.

Cudmore-Vokey, B. and E.J. Crossman. 2000. Checklists of the fish fauna of the Laurentian Great Lakes and their connecting channels. Can. MS Rpt. Fish. Aquat. Sci. 2500: v + 39p.

Emery, A. R., and G. Teleki. 1978. European founder (Platyichthys flesus) captured in Lake Erie, Ontario. Canadian Field-Naturalist 92(1):89-91.

Maitland, P. S. 1977. The Hamlyn guide to freshwater fishes of Britain and Europe. Hamlyn Publishing Group Limited, New York, NY.

Summers, R.W. 1979. Life cycle and population ecology of the flounder Platichthys flesus (L.) in the Ythan estuary, Scotland. Journal of Natural History 13:703-723.

Wheeler, A. 1978. Key to the fishes of northern Europe. Frederick Warne Ltd., London, England.

Other Resources:
FishBase Summary

Author: Pam Fuller, and Matt Neilson

Revision Date: 2/19/2020

Peer Review Date: 7/5/2011

Citation Information:
Pam Fuller, and Matt Neilson, 2024, Platichthys flesus (Linnaeus, 1758): U.S. Geological Survey, Nonindigenous Aquatic Species Database, Gainesville, FL, https://nas.er.usgs.gov/queries/FactSheet.aspx?SpeciesID=841, Revision Date: 2/19/2020, Peer Review Date: 7/5/2011, Access Date: 5/25/2024

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. [2024]. Nonindigenous Aquatic Species Database. Gainesville, Florida. Accessed [5/25/2024].

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