[5] Graptemys are small to medium-sized turtles that are significantly sexually dimorphic, with females in some species attaining as much as twice the length and ten times the mass as males.

The head, neck, and limbs exhibit bold patterns of yellow (occasionally orange or red) lines and spots against darker green, olive, or black base colors.

They primarily feed on fresh water mussels, clams, snails, insects (including larva and eggs), bryozoans, sponges, algae, and various vegetation.

Within this spectrum of food items there is significant niche partitioning among the sexually dimorphic males and females, and microcephalic, mesocephalic, and megacephalic species occurring in the same river drainages.

An extinct species from the Suwannee River drainage in Florida, Graptemys kerneri belonging to the female megacephalic subclade, was described in 2011 from Pleistocene fossil records.

[2] The trivial names, or specific epithets, of four of the species in the genus are patronyms or eponyms, named in honor of prominent herpetologist, each of whom made significant contributions to studies on North American turtles: Thomas Barbour (G. barbouri); Fred Ray Cagle (G. caglei); Carl Henry Ernst (G. ernsti); J. Whitfield Gibbons (G. gibbonsi).

[16][13] The other species are all named for various aspects of the topographic map like patterns and other markings, colors, and contours of the carapace, that are most apparent in the juveniles and young adults of these attractive turtles: G. flavimaculata, flavus = yellow, maculatus = spotted or blotched;[17] G. geographica, geographica = geographic map like;[18] G. nigrinoda, niger = black, nodus = knot, node, or knob;[19] G. oculifera, oculus = eye, fero = to bear (eye shape rings on the pleurals scutes);[20] G. pseudogeographica, pseudo = false, geographica = geographic map like;[21] G. pulchra, pulchra = beautiful;[22] G. versa, vers = to change (probably referring to the contrasting head patterns compared to G.

Females of all map turtle species can be partitioned into three groups based on head (alveolar) width and corresponding ecology and phylogeny.

Eleven of the 14 species have relatively limited distributions, restricted to river basins draining into the Gulf of Mexico, in the US states of Texas, Louisiana, Mississippi, Alabama, southwest Georgia, and the Florida panhandle.

Map turtles are predominantly lotic, living in moving water, such as rivers and larger creeks, streams, and bayous.

Larger, wider waterways allow sunlight to reach the surface, providing for the growth of aquatic vegetation and algae (food) and basking sites for Graptemys populations.

[24] The natural meandering of rivers, riparian forest, and fallen trees and deadwood in the water are all key and vital elements to sustain most map turtle populations, particularly the Gulf Coast species.

The meandering course maintains a diverse spectrum of water depths, temperatures, currents, soft and hardpan bottoms, as well as fallen trees and logs that get lodged in the bends.

A review of zoo records published in 1992 identified the maximum period of time that many species of Graptemys lived in captivity in North American zoos, ranging from eight to 35 years, including: Barbour's map turtle (G. barbouri) 31 years 8 months; false map turtle (G. pseudogeographica ssp.)

However, it is important to note that in every example these records involve turtles that were acquired by the zoos as adults from the wild, or of unknown origins and of undetermined ages.

[26]: 13 p.  Subsequently, the longevity of two female Barbour's Map Turtles (G. barbouri) of unknown ages and origin at the Columbus Zoo were reported at 37 and 43 years.

[8]: 114 p. The most frequently cited and best-documented threats to map turtle and sawback populations involve modifications of the rivers and lakes they inhabit and their take for the pet trade.

The destruction and fragmentation of habitat through the engineering of rivers and lakes, such as channelization, dams and impoundments, gravel and sand mining, pollution, clearing and development of riparian zones, and the removal of logs and deadwood from waterways are among the foremost conservation threats to map turtles.

Seemingly benign activities such as the regular use of sandbar beaches for recreation, swimming, and heavy boat traffic are known to cause turtles to abandon stretches of rivers and nesting sites.

Some lesser threats include invasive species such as fire ants (Solenopsis invicta) which are known to prey on eggs and hatchlings.

Invasive plants such as water hyacinth (Eichhornia crassipes), alligator weed (Alternanthera philoxeroides), congon grass (Imperata cylindrica), cocklebur (Xanthium stramarium), and the Chinese tallow tree (Triadica sebifera) are all known to degrade Graptemys habitat and nesting beaches.