brachinotus sexdentatus - small black sea crab among mussels in the black sea

malacostraca decapoda brachyura varunidae animal aquatic animals life arthropoda arthropods beautiful beauty biology black sea cancer claws comb jelly combjellies crab crabs crayfish crustacea crustacean crustaceans ecological ecology environment europe fauna exotic invasive species invertebrate marine reptantia creature water undersea underwater underwaters world wild wildlife