The isopods are attached to the tongue based on their pereopods which are their hook-like legs.
等足虫通过它们像钩状腿的步足吸附到(寄主的)舌头上。
英语百科
Decapod anatomy
(重定向自Pereopod)
The decapod crustacean, such as a crab, lobster, shrimp or prawn, is made up of 20 body segments grouped into two main body parts, the cephalothorax and the pleon (abdomen). Each segment may possess one pair of appendages, although in various groups these may be reduced or missing. They are, from head to tail: