Danube an important industry. The Upper Danube ecoregion alone has about 60 fish species and the Lower Danube–Dniester ecoregion has about twice as many. Among these are an exceptionally high diversity of sturgeon, a total of six species (beluga, Russian sturgeon, bastard sturgeon, sterlet, starry sturgeon and European sea sturgeon), but these are all threatened and have largely–or entirely in the case of the European sea sturgeon–disappeared from the river. The huchen, one of the largest species of salmon, is endemic to the Danube basin, but has been introduced elsewhere by humans. Important tourist and natural spots along the Danube include
Atlantic ghost crab Atlantic ghost crab The Atlantic ghost crab, "Ocypode quadrata", is a species of ghost crab, once described as an "occult, secretive alien from the ancient depths of the sea". It is a common species along the Atlantic coast of the United States, where it is the only species of ghost crab; its range of distribution extends from its northernmost reach on beaches in Westport, Massachusetts, south along the coasts of the tropical Western Atlantic Ocean to the beach of Barra do Chui, in Rio Grande do Sul in southern Brazil. Adults are greyish or the color of straw, and around