Polyipnus polliPolyipnus polli, commonly known as the round hatchetfish, is a species of ray-finned fish in the family Sternoptychidae. It occurs in deep water in the eastern Atlantic Ocean, at depths between about.EtymologyThe fish is named in honor of Max Poll, a Belgian ichthyologist, who loaned specimens of this species to Schultz.StatusPolyipnus polli is a common species within its known range and faces no particular threats. For these reasons, the International Union for Conservation of Nature has assessed its conservation status as being of "least concern".