Arthropods - Crustacean

Crustacea are mainly aquatic, carnivorous arthropods, whose body and legs are enclosed by a supporting chitinous shell. The body is divisible into head and thorax may fuse together in a cephalothorax. The head has two pairs of tactile antennae, and three pairs of limbs with food handling abilities. The walking legs are divided in two, and may have gills for breathing. The last abdominal appendage may become flattened, to form a tail fan with the end spine.