Black-knobbed Map Turtle Graptemys nigrinoda

The Black-knobbed Map Terrapin (called Turtle in America) is native to rivers of Mobile Bay in southern Alabama and Mississippi, on the US Gulf Coast.

The Black-knobbed Turtle is named after the four knobs (backward protruding vertebrae) on its back. Like several other American terrapins, the head, body, tail and legs have distinguishing patterns of yellow stripes.

The knobs reduce with age. Females (adult carapace 4-8 inches) are much larger than males (3.5-5 inches). Female and juvenile are shown above.

Threats include habitat disturbance (by humans) and predation of eggs by fish, crows, raccoons and armadillos.