A new genus and species of Cyproideidae (Crustacea: Peracarida: Amphipoda) from a tropical coral reef, SE Gulf of Mexico.

Sisalia carricarti new genus, new species, is described on specimens collected from the Sisal Coral Reef System, Southern Gulf of Mexico, Mexico. The new genus is most morphologically similar to the genus Paracyproidea, but can be distinguished by the article 2 of antenna 2 peduncle, the peduncle of the uropods and length of rami, and telson. Also, the new genus can be distinguished from the rest 18 genera of the family Cyproideidae by the following characteristics: 3-articulate mandible palp, mandible molar big and triturative; palp on maxilla 2 uniarticulate; article 2 of pereopods 3-7 rectilinear, and urosomites 1-3 not elongated. Sisalia carricarti new genus, new species, represents the second known genus and third species of cyproideid amphipods documented from the Inter-American Sea (Gulf of Mexico and Caribbean Sea), and the 19th genus and 44th species of the world cyproideid fauna. The more significant morphological characters and the geographical distribution of the 19 known genera of cyproideid amphipods are also pointed out.