Graptemys nigrinoda, commonly known as the black-knobbed map turtle, is a medium-sized aquatic turtle with a carapace length of up to 8 inches. It has a dark olive-brown carapace with yellow or white markings and a yellow plastron. Its distinguishing feature is the black knob on the posterior of the carapace. It is found in the rivers and streams of the southeastern United States, from Virginia to Florida and west to Texas. Its lifespan is up to 30 years and its current population is stable.
Name Origin: The scientific name of the organism, Graptemys nigrinoda, is derived from the Greek words "graptos" meaning "marked" and "emys" meaning "turtle". The species name, nigrinoda, is derived from the Latin words "niger" meaning "black" and "nodus" meaning "knot". This is likely in reference to the black markings on the carapace of the organism.
Related Species: Graptemys oculifera, Graptemys pseudogeographica, Graptemys pulchra, Graptemys flavimaculata, Graptemys barbouri, Graptemys caglei, Graptemys ouachitensis, Graptemys geographica