Answer: malacostracans

AnswerCrossword Clue
malacostracansMALACOSTRACAN, any of a large subclass of crustaceans having a thorax consisting of eight segments usually covered by a carapace and including the decapods and isopods
malacostracansA crustacean of the large class Malacostraca, such as a crab, shrimp, or lobster