Blue crab

Callinectes sapidus

Family Portunidae - Swimming crabs

Distinguishing
Characteristics
Carapace broader than long, compressed; color olive green to brown dorsally, yellowish to white underneath; legs olive, bluish or brown; claws are long, palms with blue and white coloration, fingers blue in adult males, red or orange in adult females, juveniles with white fingers with red spot at base of fingers; last pair of legs flattened into paddle-shaped appendages; 9 pair of spines (including the outer orbital spines) along the lateral edges of the carapace, the most posterior pair (called the lateral spines) being about 3-4 times as long as the others; 4 low blunt spines between the ocular orbits, (eye sockets), including the inner orbit spines; spines on the inner margins of merus (2nd segment from the claws) and outer carpus (segment next to claw), no spine on inner dorsal carpus.
Similar Species
Lesser blue crabs look similar, but have 6 low spines between the ocular orbits, the center pair extremely small, fingers on claws never red, juveniles with bluish spot at base of fingers.
Habitat
Bay mainly, shallow Gulf, prefers muddy and sandy bottoms
Maximum Size
25 cm (10 in) carapace width, commonly 19 cm
Other Common Names
Previous Scientific Names
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