The common smooth-hound has a grey-brown back and is white on its underneath.

It is often confused with the starry smooth-hound which has white spots on its back.

The slender smooth-hound has a very thin body and a broad, highly flattened head.

Due to the similarities between the common smooth-hound and other sharks, misidentification occurred for a long time.

The slender smooth-hound is likely a schooling species.

The dusky smooth-hound is often used as a laboratory animal and in public display at aquariums.

The starry smooth-hound can often have faded spots which leads to misidentification.

Mating occurs throughout most of the dusky smooth-hound's range from May through July.

Small fish that are preyed upon by the dusky smooth-hound include menhaden and tautog.

In certain areas, the flesh of dusky smooth-hound is marketed as fresh or dried salted for human consumption.

The diet of the slender smooth-hound is diverse, but dominated by small, benthic bony fishes and decapod crustaceans.

Whitespotted smooth-hound, a houndshark, family Triakidae, found in subtropical southeast Atlantic up to a length of 1.2 m.

The slender smooth-hound or gollumshark (Gollum attenuatus) is a species of ground shark in the family Pseudotriakidae.

Mustelus ravidus (Australian grey smooth-hound)

Harmless to humans and of no economic value, the slender smooth-hound is occasionally caught incidentally in bottom trawls and on bottom longlines.

Mustelus asterias (Starry smooth-hound)

Mustelus californicus (Grey smooth-hound)

Mustelus canis (Dusky smooth-hound)

Mustelus dorsalis (Sharptooth smooth-hound)

Mustelus fasciatus (Striped smooth-hound)

Mustelus griseus (Spotless smooth-hound)

Mustelus henlei (Brown smooth-hound)

Mustelus higmani (Smalleye smooth-hound)

Mustelus lenticulatus (Spotted estuary smooth-hound)

Mustelus lunulatus (Sicklefin smooth-hound)

In some classifications, the family is split into two sub-families, with Mustelus, Scylliogaleus, and Triakis in sub-family Triakinae, and the remaining genera in sub-family Galeorhininae.

Scottish zoologist Andrew Smith originally described the sharptooth houndshark as a species of Mustelus in 1839, as part of his work Illustrations of the Zoology of South Africa.

Although in South Africa the sharptooth houndshark is listed as a noncommercial species and thus cannot be harvested commercially, it is often mistaken for the common smooth-hound (Mustelus mustelus) by fishers.