Crustaceans belong to the phylum Arthropods along with insects, millipedes, and arachnids. Sometimes they are also called crustaceans. Almost all of them live in the sea or in fresh water. There are a total of over 50,000 species still alive. There are also a lot of fossils.
Cancers are so different that it is difficult to describe them together. Scientists also disagree on how the different species are related to each other according to evolution. They all have the following three characteristics in common: They breathe through gills and have two pairs of antennae on their heads. They also lay eggs, from which larvae develop, and later the adult animals.
Most crabs have five pairs of legs. In many crabs, the front legs have evolved into powerful pincers. These are usually of different sizes.
Crayfish take on a very important task in nature: they clean the water. They can filter out bacteria and other small creatures and even toxins.
People eat some types of crayfish, especially shrimp, crawfish, crayfish, and lobster. We call these crustaceans. They are part of the seafood on the menu. They are usually caught in traps. These are special baskets that crabs like to crawl into. You will then no longer find the exit. Some species are also bred by humans.