Fish Identification Photos: Brown Smoothhound Shark, Mustelus henlei: The Brown Smoothhound Shark has a copper-brown back and sides and a white belly. It has a slender body with a short pointed snout with horizontal oval eyes. The distance between the eyes is 3.9 to 5.6 percent of the total body length.

The mouth of the Brown Smoothhound Shark is short and angular with the upper lip fold distinctly longer than the lower lip fold.

The Brown Smoothhound Shark has fins without distinguishing marks. It has two large dorsal fins the second of which is smaller than the first and the distance between them is 19 to 24 percent of the total body length. The first dorsal fin is broadly triangular and originates closer to the pelvic fins than to the pectoral fins and has a fibrous edge (as pictured below). The anal fin is smaller than and originates under the middle of the second dorsal fin. The caudal fin is strongly asymmetrical and the lower lobe is small. The rear margins of the anal, caudal, and dorsal fins are dark, and a key to identification is that all of these fins have fibrous edges (see photos of a typical fibrous first dorsal and caudal fin below).

The Brown Smoothhound Shark has five gill slits with the last two being over the pectoral fins. It has skin dentricles on the flank with three points.

The Brown Smoothhound Shark is found near the bottom (demersal) in coastal enclosed bays with sandy and muddy bottoms at depths of up to 800 feet. It reaches a maximum length of just over 3 feet.

The Brown Smoothhound Shark is most likely confused with the Gray Smoothhound Shark, Mustelus californicus (the first dorsal fin lacks the fibrous edge), and possibly the Sicklefin Smoothhound Shark, Mustelus lunulatus (the first dorsal fin lacks the fibrous edge; the lower lobe of the caudal fin is large).

In Mexican waters the Brown Smoothhound Shark is found along the Pacific Coast of Baja California and throughout the Sea of Cortez. It is absent from along the coast of the Mexican mainland and from around Mexico's oceanic islands. It is considered to be an excellent food fish by locals.

The Brown Smoothhound Shark is a member of the Triakidae Family, which include the hound and tope sharks, and are known in Mexico as cazónes. There are 38 members of the family from 9 genera of which 7 species are found in Mexican waters. They have slender bodies with long pointed snouts, horizontal oval eyes and long angular arched mouths that reach past the front margin of the eyes. They are small in stature with the largest one reaching 6.5 feet in length. They are demersal (i.e. found close to the bottom) from the coastal shallows to over a mile deep within the water column. The hound and tope sharks are not harmful to humans. They are most active at night feeding on crustaceans, cephalopods, and fish. The Brown Smoothhound Shark is one of 22 members of the Musatelus Genus of which four are found in Mexican waters.

Brown Smoothhound Shark, Mustelus henlei: Donated to Mexfish.com by the commercial Mexican pangueros fishermen of Todos Santos, Baja California Sur, Mexico, June 2007. Size 36 inches. Description and photo courtesy of John Snow. Brown Smoothhound Shark, Mustelus henlei: Dorsal and anal fins. Description and photo courtesy of John Snow.