I believe they are supposed to pull up lava lobsters. Having used said traps prior to the change in the facings, and yes they lose the lava tag even though you can still use them in lava. I am 120 fishing in skill and the fish still don't bite. Prior to the change when I had used lava traps long before I was Legendary, lava traps would at least pull up plain crustaceans as well as named ones (unsteamed I might add). I would agree with the above post that since they changed the traps to one direction, the color of them allows them to be used in lava but they are definately broken. Just saving mine until they fix them. Have also tried them in fire dungeon on the rope bridge they don't bite there either.