This is a small (usually less than 2 feet or 55 cm in length) sleek-looking fish. Catsharks get their name from the way their eyes glow when reflecting light – like a cat’s eyes. They usually have a black or brown dorsal area, with lighter coloration on the underside of the body. Like many other sharks, the females are oviparous, meaning they lay egg cases and the young develop inside. The young swim out of the egg case after about two years.
The animal has several unique adaptations. An enlarged gill region allows the catshark to live in deep ocean areas with low dissolved oxygen levels. It also has a high concentration of squalene in its liver, an organic compound which is lighter than water and helps the shark maintain buoyancy. It feeds on a variety of small fish (e.g. lanternfish) and invertebrates.
The Filetail Catshark is found along the West Coast from Oregon to the Gulf of California. They are common on the outer continental shelf and upper continental slope at depths from 295 to 4100 feet (90 to 1,250 m). The catshark is regularly caught by bottom trawlers but not utilized in the fishing industry.