The Brown smoothhound (Mustelus henlei) is a shark belonging to the family Triakidae. It is found on the continental shelves of the eastern Pacific, from northern California to the Gulf of California, as well as Ecuador and Peru from the surface to a depth of 656 feet. They are viviparous and appear iridescent bronze in color.
Family: Triakidae – Houndsharks
Genus: Mustelus
Species: henlei
Phylum– Chordata
Class– Chondrichthyles
Common Name– Ground Sharks
Family– Triakidae
Common Name– Houndsharks
Genus– Mustelus
Species– henlei
Status: IUCN Red List LEAST CONCERN
Average Size and Length: They are born between 19-21 cm/7.4-8.2 inches. Mature males have been measured between 52-66 cm/1.7-2.1 feet, and mature females between 51-63 cm/1.6-2 feet. The maximum recorded has been measured at 95 cm/3 feet.
Teeth and Jaw: The teeth are pavement-like and are high-cusped. The small teeth are asymmetric. The upper teeth have a median cusp flanked by a defined notch and smaller cusp while the lower teeth have cusps that are more erect.
Head: The head is short, with a somewhat long snout. The eyes are close set, and the nostrils are widely spaced.
Denticles: Dentition consists primarily of tricuspidate denticles with longitudinal ridges.
Tail: The caudal peduncle is long.
Demographic, Distribution, Habitat, Environment and Range: The Brown smoothhound is found in the east Pacific in northern California to Mexico, and also Ecuador to Peru (43° N and 18° S). They are found on the continental shelf in the intertidal zone to at least 656 feet. They are most abundant in enclosed, shallow muddy bays. Of the three members of its genus, the Brown smoothhound is the most tolerant of cold water. They are demersal.
Diet: Crustaceans primarily make up their diet, but they will also eat polychaete worms, and some fish.
The Brown smoothhound falls prey to the Sevengill shark.
Aesthetic Identification: The Brown smoothhound is slender and unspotted, is typically iridescent bronze-brown or even greyish colored dorsally, and white ventrally. The trailing dorsal fin edges appear broadly frayed with dark margins or bare ceratotrichia.
Biology and Reproduction: They are viviparous having 3-5 pups per litter. Gestation is thought to be around 10 months. They live between 13-15 years.
Reported parasites are the copepods Pandaris bicolor and Perissopus oblongatus.
Behavioral Traits, Sensing and Intelligence: They mainly patrol the bottom, and sometimes in midwater and at the surface. They are often found resting on the seabed. One shark that was tagged migrated 160 km/99 miles in three months.
Speed: In captivity, they are agile and active swimmers.
Brown Smoothhound Future and Conservation: They are currently of least concern. They are common where they occur and are heavily fished. They are also kept in large aquaria.
Brown Smoothhound Recorded Attacks on Humans: Not a threat to humans.