The carapace of the turtle has various color patterns that change over time. Hatchlings of "Chelonia mydas", like those of other marine turtles, have mostly black carapaces and light-colored plastrons. Carapaces of juveniles turn dark brown to olive, while those of mature adults are either entirely brown, spotted or marbled with variegated rays. Underneath, the turtle's plastron is hued yellow. "C. mydas" limbs are dark-colored and lined with yellow, and are usually marked with a large dark brown spot in the center of each appendage.