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.

Mauremys reevesii
Mauremys reevesii
(Chinese Three-keeled Pond Turtle)

Copyright Info
Mauremys reevesii (Gray, 1831)

Common name: Chinese Three-keeled Pond Turtle

Synonyms and Other Names: Reeve's turtle

Taxonomy: available through www.itis.govITIS logo

Identification: Three strong keels on the carapace, which is usually brown. The legs are webbed and the tail is quite long. Coloration: body usually grey with yellowish spots and the head has a pattern of stripes. Some Reeve's turtles entire body and soft parts might be dark brown or completely black. Reaches sexual maturity in China at 4 to five inches; grows as large as 14 inches in Japan.

Size: 4-14 inches

Native Range: Mauremys reevesii is native to most of temperate and subtropical China, North Korea and South Korea; populations also occur in Taiwan, Hong Kong and Japan (van Dijk, 2013).

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 Mauremys reevesii are found here.

StateFirst ObservedLast ObservedTotal HUCs with observations†HUCs with observations†
CA199419982Lower Sacramento; San Gabriel
MA199219921Cape Cod

Table last updated 2/29/2024

† Populations may not be currently present.

Means of Introduction: Pet escape or release.

Status: Failed in California, Guam, and Massachusetts.

Impact of Introduction: The impacts of this species are currently unknown, as no studies have been done to determine how it has affected ecosystems in the invaded range. The absence of data does not equate to lack of effects. It does, however, mean that research is required to evaluate effects before conclusions can be made.

Remarks: None.

References: (click for full references)

Behler, J.L. and F.W. King. 1979. The Audubon Society Field Guide to North American Reptiles and Amphibians. Alfred A. Knopf, Inc. NY.

Cardoza, J.E., G.S. Jones, T.W. French, and D.B. Halliwell. 1993. Exotic and translocated vertebrates of Massachusetts. Massachusetts Division of Fisheries and Wildlife Fauna of Massachusetts Series, Publication #17223-110-200-11/93-C.R. Volume 6. 95 pp.

Conant, R. and J.T. Collins. 1991. A Field Guide to Reptiles and Amphibians: Eastern and Central North America. Peterson Field Guide Series. Houghton Mifflin Company, Boston. Third ed.

Ernst, C.H., J.E. Lovich, and R.W. Barbour. 1994. Turtles of the United States and Canada. Smithsonian Institution Press, Washington, D.C.

Holland, D.C. - herpetologist, Fallbrook, CA.

Leberer, T. 2003. Records of freshwater turtles on Guam, Mariana Islands. Micronesica 35-36:649-652.

Spinks, P.Q., G.B. Pauly, J.J. Crayon, and H.B. Shaffer. 2003. Survival of the western pond turtle (Emys marmorata) in an urban California environment. Biological Conservation 113(2):257-267.

van Dijk, P.P. 2013. Mauremys reevesii. The IUCN Red List of Threatened Species. Version 2015.2. http://www.iucnredlist.org. Downloaded 23 July 2015.

Author: Pam Fuller, Ann Foster, and Robert S. Powell

Revision Date: 4/19/2018

Citation Information:
Pam Fuller, Ann Foster, and Robert S. Powell, 2024, Mauremys reevesii (Gray, 1831): U.S. Geological Survey, Nonindigenous Aquatic Species Database, Gainesville, FL, https://nas.er.usgs.gov/queries/FactSheet.aspx?speciesID=1228, Revision Date: 4/19/2018, Access Date: 2/29/2024

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 [2/29/2024].

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