Reptiles of North Carolina
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NC Records

Graptemys geographica - Northern Map Turtle

Graptemys geographica
Taxonomy
Class: ReptiliaOrder: TestudinesFamily: EmydidaeSubfamily: DeirochelyinaeOther Common Name(s): Common Map Turtle- Northern Map Turtle
Taxonomic Comments: One of fourteen species in this strictly North American genus (SSAR, 2016). Two species are now recorded in North Carolina.
Species Comments: No subspecies are currently recognized for this species (SSAR, 2016)
Identification
Basis for Records: For specimens found at Hiwassee Lake, or now at the French Broad River near Hot Springs, a good quality photograph showing the head pattern and shape should be sufficient to identify this species. For individuals located well away from this area, i.e., in areas outside the natural range of this species, specimens may need to be collected and sent to the NC Museum of Natural Sciences for determination.
Description: The post-orbital spot in this species is triangular and isolated from the other markings on the head and neck. In G. pseudogeographica kohni, a semi-circular line wraps around the rear of the eye; the iris is also often white in that species, but dark in geographica (Ernst and Lovich, 2009).
Morphological Features: The carapace has a low keel, with vertebral spines present in juveniles, low in males, and absent in females (Ernst and Lovich, 2009). Females have enlarged heads (Braswell and Palmer, 1995). The upper jaw lacks a notch, unlike our other pond and river turtles, and its crushing surface is broad (Ernst and Lovich, 2009).
Technical Reference: Ernst and Lovich (2009)
Field Guide Descriptions: Beane et al. (2010); Powell et al. (2016)
Online Photos:    Google   iNaturalist   GBIF
Distribution in North Carolina
Distribution Comments: This species was only speculated to occur in North Carolina by Palmer and Braswell (1995). There are now several records for it, based on specimens deposited in the NC Museum of Natural Sciences, that confirm its presence. All of these were from Hiwassee Lake in Cherokee County on the North Carolina-Tennessee state line (Beane et al., 2010). In 2025, the first record for this species from the French Broad River in Madison County was submitted by Rob Van Epps. Like the those from the Hiwasee River, this record comes from another tributary of the Tennessee River, which is widely occupied by this species, at least at lower elevations.
Distribution Reference: Ernst and Lovich (2009)
County Map: Clicking on a county returns the records for the species in that county.
Key Habitat Requirements
Habitat: Common Map Turtles are inhabitants of large lakes, as well as rivers and larger streams with low rates of flow (Beane et al., 2010). In North Carolina, only water bodies in the Hiwassee and French Broad drainages are inhabited.
Biotic Relationships: Map Turtles are specialized predators of freshwater mussels and snails, whose shells they crush using the hardened plates on their jaws.
Life History and Autecology
Aquatic Life History: Hibernation takes place at the bottoms of rivers, where water circulation is important in maintaining high oxygen conditions needed for respiration through the skin, pharynx, or cloaca (Ernst and Lovich, 2009). Emergence occurs in early spring when the adults spend significant time basking.
General Ecology
Adverse Environmental Impacts
Status in North Carolina
NHP State Rank: S1
Global Rank: G4G5
Status in North Carolina: SC

Photo Gallery for Graptemys geographica - Northern Map Turtle

1 photos are shown.

Graptemys geographicaRecorded by: Rob Van Epps
Madison Co.
Comment: Adult female