Piranha beetles were colorfully-shelled carnivorous insects that lived on the jungle moon of Yavin 4. Though they were only three centimeters long, they gathered in large swarms which could kill much larger prey, like runyips, by eating the flesh directly off living beings. Piranha beetle swarms built hives made from chewed vegetation and saliva in Yavin 4's treetops. Each hive had a queen that led the hive's reproductive and food-gathering activities. When Jacen Solo attended the Jedi Praxeum on Yavin 4, he kept two piranha beetles as pets. He kept them calm by using the Force.