walls bearing fine, lengthwise grooves; the top of the case is squared off, while the bottom is rounded with a short membraneous projection. Females lay eggs throughout the year, with a peak in December and January. The young shark hatches at about long. Males mature sexually at long, and females at long. Human interactions The International Union for Conservation of Nature (IUCN) assesses it as Least Concern. It is caught incidentally to an unknown degree in bottom trawls operated by commercial deepwater fisheries off Japan and in the East China Sea. References broadfin sawtail catshark Fish of Japan Endemic fauna of Japan Taxa named by Kazuhiro Nakaya broadfin sawtail catshark