Possibly the most unusual location is a population which occupies the brackish water cooling canals at the Turkey Point nuclear power plant in Florida. This species also constructs long burrows for aestivation and as a retreat from adverse conditions. Considerable overland distances can also be travelled in search of new habitats. Dorsal armour is irregular and much reduced in comparison with other species. There is a distinctive swelling in front of each eye, visible in all except the hatchlings.
Adults take on an olive brown colour.
Iris is silvery. Also takes birds. Feeds primarily at night. Juveniles take small fish and invertebrates. Often blamed for the disappearance of domestic animals in more populated areas.