Freshwater crab Freshwater crab There are around 1,300 species of freshwater crabs, distributed throughout the tropics and subtropics, divided among eight families. They show direct development and maternal care of a small number of offspring, in contrast to marine crabs which release thousands of planktonic larvae. This limits the dispersal abilities of freshwater crabs, so they tend to be endemic to small areas. As a result, a large proportion are threatened with extinction. There are more than 1,300 described species of freshwater crabs, out of a total of 6,700 species of crabs across all environments. The total number of species of freshwater
Saltwater fish called estuaries, areas when oceans and rivers meet creating a mixture of salt water and freshwater making a different habitat for different types of fish and creatures to live in. The ocean is home to organisms as large as whales and as small as microscopic marine organisms such as phytoplankton. However, the vast majority of ocean life that humans are exposed to is simple saltwater fish. Saltwater fish can live in the deepest depths of the ocean where no sunlight can penetrate, but they can also live on the surface of the water. Saltwater fish Saltwater fish, also called marine