rhizocephalan barnacle根头目甲壳动物藤壶
N（名词） any parasitic crustacean of the order Rhizocephala, esp Sacculina carcini, which has a saclike body and sends out absorptive processes into the body of its host, the crab: subclass Cirripedia (barnacles) 根头目甲壳动物
ADJ（形容词） of, relating to, or belonging to the order Rhizocephala 根头目甲壳动物的