This species, Panaque bathyphilus, Panaqolus nix, Loricaria spinulifera and L. pumila are the only loricariid catfish species known to occur in a deep water form with reduced pigment and eyes (similar to cavefish), and another "normal" form in shallower waters.[3][7][8][9]P. pankimpuju and a few other loricariid catfish species of the main stream of large South American rivers have greatly elongated streamers on their tail.[3] It is speculated that this may serve as an early warning system against the large predatory catfish that also roam their habitat. Positioned with the head towards the water current, as typical of loricariid catfish, the long tail streamers of P. pankimpuju are the first to be contacted by a large predator that hunts against the current, perhaps allowing it to escape.[3]