Graptemys is a genus of freshwater turtles containing 14 species, commonly known as map turtles. Graptemys are small to medium-sized turtles that are sexually dimorphic, with females attaining as much as twice the length and ten times the mass as males in some species. Depending on the species, adult males range from 7–16 cm (2.75–6.25 in), adult females 10–29.5 cm (4–11.62 in), and hatchlings 2.5–3.8 cm (1–1.5 in), although some sources indicate female Barbour's map turtles (Graptemys barbouri) grow to 33 cm (13 in) in length. Most species have a distinctive dark pigmented keel that is often notched or serrated running down the center of the carapace and serrated scutes on the rear margin. 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. The patterns on the head can be important characters in identifying the various species. The common name "map turtle" is derived from the intricate patterns on their shells that are suggestive of topographical maps, although the patterns are more apparent in some species than others, and often become obscure in older specimens. Some species are occasionally called "sawbacks", in reference to the serrated keels on their shell.

The red-eared slider or red-eared terrapin (Trachemys scripta elegans) is a subspecies of the pond slider (Trachemys scripta), a semiaquatic turtle belonging to the family Emydidae. It is the most popular pet turtle in the United States, is also popular as a pet across the rest of the world, and is the most invasive turtle. It is the most commonly traded turtle in the world. The red-eared slider is native from the Midwestern United States to northern Mexico, but has become established in other places because of pet releases, and has become invasive in many areas where it outcompetes native species. The red-eared slider is included in the list of the world's 100 most invasive species.

Last updated Mar 23rd 2024