Sally Lightfoot Crab
The Sally Lightfoot Crab (also referred to as nimble spray crab or urchin crab) is very striking, very flat, and very often confused with the larger and unrelated terrestial crab called the "Sally Lightfoot." When keeping any crab a good rule of thumb is to keep one crab per ten gallons of water.
Scientific Name: Percnon gibbesi
Max size: 2 to 3 inches