The roughtail catshark or marbled catshark (Galeus arae) is a common species of catshark, part of the family Scyliorhinidae. It is found at a depth of in the northwestern Atlantic Ocean, the Gulf of Mexico, and the Caribbean Sea, from North Carolina to Costa Rica. Individuals of different sexes and ages are segregated to some degree. A small species not exceeding in length, the roughtail catshark has a slender body with a marbled color pattern of dark saddles and spots, and a prominent crest of enlarged dermal denticles along the dorsal edge of its caudal fin. This species feeds mainly on shrimp and is oviparous. It is caught incidentally in shrimp trawls, though trawl fisheries within its range mostly do not operate at the depths it inhabits. As a result, the International Union for Conservation of Nature has listed it under Least Concern. Taxonomy John T. Nichols of the American Museum of Natural History originally described the roughtail catshark as Pristiurus arae in a 1927 issue of American Museum Novitates. He named the species after the trawler Ara, which collected the first two specimens, both long immature females, off Miami Beach on March 31, 1926. Later authors have recognized Pristiurus as a junior synonym of Galeus. The Antilles catshark (G. antillensis) and the longfin sawtail catshark (G. cadenati) were regarded as subspecies of G. arae, until taxonomic revisions were published by Hera Konstantinou and colleagues in 1998 and 2000. The three species, along with the southern and Springer's sawtail catsharks (G. mincaronei and G. springeri), are grouped together in the G. arae species complex. Description Probably the smallest member of the G. arae species complex, the roughtail catshark grows no longer than . It has a slender, firm body and a slightly flattened head. The snout is rather long and pointed, with the nostrils divided by triangular skin flaps in front. The horizontally oval eyes are equipped with rudimentary nictitating membranes (protective third eyelids), and lack prominent ridges underneath. There is a tiny spiracle behind each eye. The mouth is large and forms a broad arch, with moderately long furrows around the corners. The teeth are small and number 59–65 rows in the upper jaw and 58–60 rows in the lower jaw. Each tooth has a thin central cusp flanked by 1–3 pairs of cusplets on either side. There are five pairs of gill slits. The first dorsal fin has