The blue crab Callinectes ornatus is a decapod crustacean in the Portunidae family. It is a strong and agile swimmer powered by a pair of flat, oar shaped rear legs called swimmerets. Swimmerets allow C. ornatus to rapidly swim backwards, sideways, and sometimes forward (Barnes 1980). The color of this species varies considerably. Adult males have a carapace that is uniformly olive to dark brown with a large orange spot posteriorly that can appear round to blotchy (Gore and Grizzle 1974, Gore 1977, Williams 1984). There are distinct ivory white tips on all the spines on the front of the carapace (Gore 1977). Juveniles are not as brilliantly colored appearing olive-yellow to greenish. The length and curvature of the reproductive organs (gonopods) are distinctive in mature males for each of the Callinectes species (Gore 1977, Barnes 1980) See illustrations from Williams (1974) below.
- Barnes RD. 1980. Invertebrate Zoology. Saunders College/Holt, Rinehart and Winston, Philadelphia, PA. 725 p.
- Branco JO, Lunardon-Branco MJ, Verani JR, Schveitzer R, F. Souto FX, and WG Vale. 2002. Natural diets of Callinectes ornatus Ordway, 1963 (Decapoda, Portunidae) in the Itapocoroy inlet, Pehna, SC, Brazil. Braz. Arch. Biological Technology 45:35-40
- Gore RH. 1977. Studies on decapod crustaceans from the Indian River region of Florida.A field character for the rapid identification of the swimming crabs Callinectes ornatus Ordway, 1963 and C. similis Williams, 1966 (Brachyura: Portunidae). Northeast Gulf Science 1:119-123.
- Gore RH and RE Grizzle. 1974. Studies of the decapod crustacean from the Indian River Lagoon region of Florida.Callinectes bocourti A. Milne Edwars, 1979 (Decapoda, Portunidae) from the central east coast of Florida. Crustaceana 27:306-308.
- Negreiros-Fransozo ML, Mantelatto FLM, and A Fransozo. 1999. Population biology of Callinectes ornatus Ordway, 1863 (Decapoda, Portunidae) from Ubatuba (SP), Brazil. Scientia Marina 63:157-163.
- Norse EA. 1978. An experimental gradient analysis: hyposalinity as an "upstress" distributional determinant for Caribbean portunid crabs. Biological Bulletin 155:586-598.
- SCDNR. Undated. Blue Crabs of the South Atlantic Bight. Adobe pdf document available online.
- Williams AB. 1974. The swimming crabs of the genus Callinectes (Decapoda: Portunidae). Fishery Bulletin 72:685-798.
- Williams AB. 1984. Shrimps, Lobsters, and Crabs of the Atlantic Coast of the Eastern United States, Maine to Florida. Smithsonian Institution Press, Washington DC. 550 p.
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