Species of decapod crustaceans and their distribution in the American marine zoogeographic provinces

Fourteen marine zoogeographic provinces and two subprovinces were established for the Americas. The number of species of marine decapod crustaceans recorded in the supralittoral, intertidal, eulittoral and sublittoral (continental shelf to 200-300 m) including both, continental coasts from the Arctic Polar region in the north to Cabo de Hornos in the south is estimated at 2472 species. The results of this study on the biodiversity and distribution of decapod species call attention to a common characteristic of typical epifaunal groups of organisms with a large range of latitudinal geographic distribution: a high number of species in tropical regions on both coasts and a pronounced decrease of taxa towards the polar regions that generates a clear clinal distribution. The Caribbean Province showed the largest diversity which, with a total of 1058 species was higher than that of the tropical Panamic Province where 825 species were registered. With regard to the species richness in the nine major groups of Decapods, the largest number was found in the Brachyura covering 1090 estimated species followed by the Caridea with 536 species, the Anomura with 509 species, the Thalassinidea with 157 and the Penaeoidea with 96. The remaining four decapod taxa are represented only by a small number of species.