The trapinfilter has split from its ancestor the trapinout. It is no longer mobile and spends all of its life filter-feeding just like the juvenile stage. Its worm-like lures have now become digging anchors to keep it upright in the sand. Its front grasper have grown bristles to capture microorganisms in. Once full they will retract them into the shell to be licked off. Its is no longer poisonous and will dig straight down into the sand if a predator comes.
Every summer they will spawn huge clouds of spore into the coastal waters. This causes a feeding frenzy for about a week. They do this to maximize the number of offspring that will survive.