hermit crab (clibanarius erythropus), crayfish protrudes from the shell of a mollusk rapana

animal aquatic arthropoda benthos biology black sea fauna cancer claws clibanarius crab crawfish crayfish crustacea crustacean decapoda ecology erythropus europe exoskeleton hermit invertebrate life malacostraca marine nature organisms rapana reptantia saltwater biological shrimp under water undersea underwater world wild wildlife