It is additionally characterized by a short head and snout with a pair of slender barbels that do not reach the mouth, and two dorsal fins that are placed far back on the body.

This species is an opportunistic predator that feeds on a wide variety of fishes and invertebrates; it favors cephalopods and frequents the spawning grounds of the chokka squid (Loligo reynaudi).

However, there is no data suggesting its numbers have declined, so the International Union for Conservation of Nature (IUCN) has assessed the pyjama shark as least concern.

The pyjama shark was originally described as Squalus africanus by German naturalist Johann Friedrich Gmelin in 1789, in the thirteenth edition of Systema Naturae.

[4] A bottom-dwelling inhabitant of temperate inshore waters, the pyjama shark is found off South Africa, from Table Bay off Cape Town to north of East London.

It is most abundant off the Western Cape, and may venture as far as Saldanha Bay in the west and KwaZulu-Natal in the east; old records from Mauritius, Madagascar, and Zaire are almost certainly erroneous.

The eyes are horizontally oval and placed rather high on the head, with rudimentary nictitating membranes (protective third eyelids) and a thick ridge running underneath.

The teeth have a slender central cusp flanked by a pair of small cusplets; those of adult males are slightly thicker than those of females.

Adult males have a pair of short, thick claspers, with the inner margins of the pelvic fins partially fused over them to form an "apron".

[5][7] Rather slow-swimming, the pyjama shark spends most of the day resting in caves or crevices or amongst kelp, emerging at night to actively forage for food.

As the female squid descend to the sea floor to attach their eggs, guarded by the males, they become vulnerable to the sharks' ambush attacks.

[5] Large numbers of pyjama sharks are caught incidentally by commercial fisheries using longlines, gillnets, beach-seines, and bottom trawls; they are also readily hooked by recreational anglers, especially during the summer when they aggregate.

[1][8] The toll taken by fishery bycatch is likely greatly underestimated, as many fishers who use line gear regard pyjama sharks as pests that "steal" bait, and kill them before discarding them.

Despite its limited distribution and a recent increase in fishing pressure on small sharks in the region, there is no evidence to suggest that its population has declined.