Graptemys

rdf:langString Graptemys

rdf:langString Agassiz, 1857

rdf:langString Graptemys pseudogeographica,

rdf:langString Species

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rdf:langString Graptemys (Agassiz, 1857) Malacoclemmys Cope, 1875

rdf:langString Malaclemys (McDowell, 1964)

rdf:langString Graptemys

rdf:langString 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. They are endemic to North America, where most species occur in the rivers of the Gulf Coast of the United States, although three species are more wide-ranging, dispersed throughout the eastern two thirds of the greater Mississippi River basin, into the Great Lakes region, and east to New York and southeast Canada. Most Graptemys are lotic, river turtles, having a preference for moving water and larger lakes, and with long legs, broad feet, and long fully webbed digits they are well adapted for swimming in currents. They primarily feed on fresh water mussels, clams, snails, insects (including larva and eggs), bryozoans, sponges, algae, and various vegetation. Fish only appear in the diets of a few species and then only in a relatively small percentage of the diet. 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. Like all turtles, map turtles are oviparous, typically laying eggs from late June to August. Females lay two to 15 eggs per clutch and depending on a number of variables such as species, size, and age among other factors, may skip a year between clutches, or lay as many four clutches a year. Seven of the 14 species are listed as either near threatened, vulnerable, or endangered by the IUCN Red List as of 2021, and two species, the yellow-blotched map turtle (G. flavimaculata) and the ringed map turtle (G. oculifera) are listed as threatened by the U.S. Federal Government.