The filetail catshark (Parmaturus xaniurus) is an Eastern Pacific endemic deepwater catshark ranging from Oregon to the Gulf of California. Adults are epibenthic and found near areas of rocky vertical relief over soft mud bottoms on the outer continental shelf and upper slope at depths of 91 to 1,251 m, juveniles are mesopelagic, found around 500 m off the bottom in waters over 1,000 m deep. Reaches a maximum size of 60 cm TL. An oviparous species, females deposit eggcases throughout the year with concentrated reproductive output July through September. There is no information available on the age and growth, longevity, fecundity, abundance or mortality of this species. It is not targeted by commercial fisheries or utilized for human consumption, but is known to be incidental catch in long