Stone Crab Speciation
Two species of stone crabs exist in the Southeastern United States: Menippe mercenaria in the peninsula of Florida, and Menippe adina in the northern and western Gulf of Mexico. The two species differ in coloration and genetic makeup; they also differ somewhat in reproduction, salinity and temperature tolerance, and ecology. The table and pictures below show the differences in color pattern and habitat.
M. mercenaria
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Body and Claw Color: Deep chocolate to maroon
Body and Claw Markings: Usually solid, occasional mottling of light brown
Leg Color and Markings: Solid deep chocolate to maroon
Habitat: Limestone sand, rocky outcrops, seagrass beds
M. adina
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Body and Claw Color: Tan to light or medium gray
Body and Claw Markings: Black spotted, spots usually small but uniform
Leg Color and Markings: Dark brown, distinct white bands
Habitat: Limestone sand, rocky outcrops, seagrass beds