Native to the United States

False map turtle

Graptemys pseudogeographica (Gray, 1831)

Subspecies: northern false map turtle, Mississippi map turtle
Data updated October 2026

False map turtle basking on a river log with legs stretched out, showing the knobbed keel and olive shell
Fig. 1 — An adult basking on a snag, legs and neck stretched out to soak up sun.
Close view of a false map turtle's head showing yellow neck stripes and the yellow mark behind the eye
Fig. 2 — The yellow mark behind the eye is usually a thin bar or L shape.

At a glance

A river turtle of the central US with a saw-edged shell and a row of knobs down its back. Females grow nearly twice as long as males. It basks on logs and is usually among the first turtles to dive when a boat comes near.

01

Identification

The false map turtle has a brown or olive upper shell with a raised keel down the middle, studded with dark knobs, and a strongly saw-toothed rear edge. Thin light lines outline dark blotches on the side plates. The lower shell is plain yellow in adults. The head, neck and legs are brown or olive with thin yellow stripes, and the eyes are often whitish or pale yellow. The mark behind each eye is the key detail: usually a narrow yellow bar or backward L shape, with no large spot under the eye or on the chin.

  1. 01Knobbed keel. A low ridge with dark knobs runs down the center of the shell, sharpest in young turtles.
  2. 02Saw-edged shell. The rear edge of the upper shell is strongly serrated.
  3. 03Head mark. A thin yellow bar or L-shaped mark behind the eye, with up to three neck stripes reaching it.

Commonly confused with

These share the same basking logs but lack the knobbed keel. Its closest lookalikes are other map turtles, especially the Ouachita map turtle, which has a large yellow spot behind the eye plus spots under the eye and on the chin.

02

Size

02 in4 in6 in8 in10 in12 in Large adult female · about 9 in (23 cm) shell

Shell length runs from about 3½ to nearly 11 inches (9–28 cm), but the sexes differ a lot. Females measure 6 to 10½ inches, while males stay at 3½ to 6 inches. Males also have long front claws and a longer tail.

03

Range & habitat

False map turtles basking on a log in a wide, muddy river backwater
Fig. 3 — Big rivers with plenty of fallen logs for basking are prime habitat.

False map turtles live in the large river systems of the central United States, including the Missouri, upper Mississippi and Ohio drainages, from Indiana, Kentucky and Illinois west to Minnesota, Missouri, Nebraska and the Dakotas. In Missouri, the southern subspecies, the Mississippi map turtle, overlaps with the northern form in the east and southeast of the state.

They prefer big rivers and their backwaters with muddy bottoms, some aquatic plants and many places to bask. They also use sloughs, oxbow lakes, lakes and reservoirs. In one Missouri River study, females used the main channel more, males favored permanent scour ponds, and young turtles used shallow, temporary floodplain wetlands with more food and fewer predators.

04

Diet & predators

False map turtles are omnivores. They feed mainly in the early morning on snails, freshwater mussels, crayfish and aquatic insect larvae, and they also scavenge dead fish and eat water plants. In Illinois, plants and animals make up roughly equal parts of the diet. They have even been seen eating periodical cicadas that fell into a Missouri lake.

Feeds on

  • Snails and freshwater mussels
  • Crayfish
  • Aquatic insect larvae
  • Dead fish
  • Aquatic plants

Preyed on by

  • Raccoons (nests, eggs and hatchlings)
  • River otters, skunks and red foxes (nests)
  • Snakes and herons (eggs and hatchlings)
  • Fly larvae that attack hatching eggs
Freshwater snail on a submerged rock
Prey — freshwater snails.
Raccoon walking along a riverbank
Predator — raccoon, the main nest raider.

05

Behavior & seasons

These turtles spend much of the day basking on logs and rocks, with head, neck and legs stretched out, sometimes for hours. They are very wary. A passing boat sends them diving, though they usually climb back out within about 10 minutes if left alone.

They are active from about early April to late October. Winter is spent buried in mud at the bottom of sloughs, lakes and river backwaters, and they likely do not eat during that time. In the southern third of Missouri they can be partly active in mild winters.

06

Reproduction

Mating takes place in the water, mostly in April and May, with some breeding reported in fall. From late May or early June through July, females travel to sandy islands, field edges and open spots with loose soil to dig a flask-shaped nest about 3½ to 6 inches deep. A clutch holds 8 to 22 eggs, averaging about 14, and females can lay two or three clutches a year. The eggs hatch after about two months, in late summer or early fall. Missouri biologists report that predators destroy nearly 90% of nests within 24 hours of laying. Males mature at 4 to 6 years and females at 8 to 12.

07

Conservation

The false map turtle is not listed under the US Endangered Species Act, and in Missouri it is the most common turtle in the Missouri and Mississippi rivers. The main concerns are habitat change and loss on big rivers, drowning in fishing gear and past collecting. Lowering floodplain water levels in winter can kill young turtles when cut-off pools freeze. Young map turtles are sold as pets, and released animals are a concern overseas. Never release a pet turtle into the wild.

08

In captivity

False map turtles turn up in the pet trade, often as hatchlings. They are generally calm and rarely bite, but they are strong swimmers that need much more room than most beginners expect, and females grow to over 10 inches.

  • Housing. A large, well-filtered aquatic tank or pond with room to swim, scaled up for big females.
  • Basking. A dry basking spot where the turtle can dry its shell completely, with a basking lamp of at least 80°F.
  • Lighting. Multi-spectrum lighting that includes UVB over the basking area.
  • Food. Mostly animal foods such as snails and aquatic insects, with some plant material.

See a reptile vet if a map turtle stops eating, has soft or discolored patches on its shell, or stops basking. More pet care guides

Keep reading

Sources

Data updated October 2026 · How we build these pages