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 caspica
Mauremys caspica
(Caspian Turtle)

Copyright Info
Mauremys caspica (Gmelin, 1774)

Common name: Caspian Turtle

Taxonomy: available through www.itis.govITIS logo

Identification: Mauremys caspica is a tan to black/brown, highly aquatic turtle. The carapace is olive to black often with yellow/cream-colored patterning on the scutes. It exhibits a dorsal keel, most prominent in juveniles, with no serrations along its edge. The lower shell, or plastron, is notched posteriorly and is black with yellow markings or yellow with reddish to brown blotches. The head and legs are olive, brown or black. The head exhibits yellow stripes, while the legs have yellow to gray stripes or network patterns (Ernst and Barbour, 1989).

Size: carapace length of 23.5 cm

Native Range: Mauremys caspica is native to the eastern Mediterranean countries as well as those countries bordering the Aegean and Black seas. It ranges from the southwestern previous Soviet Union and central Iran to Saudi Arabia and Israel, northward through Turkey to Bulgaria and Greece to Serbia and Montenegro (Yugoslavia) (Ernst and Barbour, 1989; Cardoza et al, 1993). They reside in permanent freshwater bodies ranging from pristine to severely polluted and are occasionally found in brackish water (Ernst and Barbour, 1989; Highfield, 2002).

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 caspica are found here.

StateFirst ObservedLast ObservedTotal HUCs with observations†HUCs with observations†
MA198719871Blackstone River

Table last updated 4/17/2024

† Populations may not be currently present.

Means of Introduction: The means of introduction is unknown; it is presumed to be an escaped or release pet.

Status: Just one specimen was collected, so the species is not considered established (Cardoza et al., 1993).

Impact of Introduction: Unknown, but likely no impacts due to failure to establish.

Remarks: Females nest from June to July producing clutches of 4-6 white eggs. Hatchlings have a 33 mm carapace and are brighter than adults (Ernst and Barbour, 1989). Members of the genus Mauremys are called the stripe-necked turtles and are found in Asia and Mediterranean countries (Highfield, 2002; ITIS 2002).

References: (click for full references)

Cardoza, J. E., G. S. Jones, T. W. French, and D. B. Halliwell. 1993. Exotic and Translocated Vertebrates of Massachusetts. Fauna of Massachusetts Series 6. Massachusetts Division of Fisheries and Wildlife, Westborough, Massachusetts. 106 pp.

Ernst, C. H., and R. W. Barbour. 1989. Turtles of the World. Smithsonian Institution Press, Washington, D.C. and London. 313 pp.

Highfield, A. C. 2002. An introduction to the Mauremys turtles of the Mediterranean (online). Tortoise Trust. Available at URL: www.tortoisetrust.org/articles/mauremys.html.

ITIS: Integrated Taxonomic Information System. 2002. Mauremys caspica (Gmelin, 1774)(online). Available at URL: http://www.itis.usda.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=551928.

Author: McKercher, E.

Revision Date: 4/6/2021

Citation Information:
McKercher, E., 2024, Mauremys caspica (Gmelin, 1774): U.S. Geological Survey, Nonindigenous Aquatic Species Database, Gainesville, FL, https://nas.er.usgs.gov/queries/factsheet.aspx?SpeciesID=1248, Revision Date: 4/6/2021, Access Date: 4/17/2024

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.


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Citation information: U.S. Geological Survey. [2024]. Nonindigenous Aquatic Species Database. Gainesville, Florida. Accessed [4/17/2024].

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