"Uca" redirects here. For other use, see UCA

UCA

UCA can stand for:* Under color addition* Unicode collation algorithm* The University for the Creative Arts, England* The United States of Central America, existing in Latin America from 1823 to 1840* The Uniting Church in Australia...

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A fiddler crab, sometimes known as a calling crab, may be any of approximately 100 species of semi-terrestrial marine crab

Crab

True crabs are decapod crustaceans of the infraorder Brachyura, which typically have a very short projecting "tail" , or where the reduced abdomen is entirely hidden under the thorax...

s which make up the genus Uca. As members of the family Ocypodidae

Ocypodidae

Ocypodidae is a family of crabs that includes the ghost crabs and fiddler crabs. Other genera previously included in the family are now treated as members of separate families in the superfamily Ocypodoidea, such as Ucididae, Dotillidae and Macrophthalmidae....

, fiddler crabs are most closely related to the ghost crab

Ghost crab

Ghost crabs, also called sand crabs, are crabs of the genus Ocypode, common shore crabs in many countries. Characteristics of the genus include one claw being larger than the other, but this difference is not as marked as in male fiddler crabs....

s of the genus Ocypode

Ghost crab

Ghost crabs, also called sand crabs, are crabs of the genus Ocypode, common shore crabs in many countries. Characteristics of the genus include one claw being larger than the other, but this difference is not as marked as in male fiddler crabs....

. This entire group is composed of small crabs – the largest being slightly over two inches across.