Flapnose Houndshark

• Maximum length1.02 m (3.3 ft); most adults 75–90 cm
• WeightNo reliable measurement (a few kilograms)
• LifespanUnknown; no age study exists
• Depth rangeSurf zone and shallow shelf; no precise maximum published
• DietRock lobsters, crabs, shrimps, squid
• IUCN statusVulnerable (assessed 2018, published 2019)

How to recognise a flapnose houndshark

Look at the nose first. In most houndsharks the front edge of each nostril carries a small triangular flap; in this species the two flaps have grown enormous and merged into a single broad curtain of skin that reaches back over the mouth, so that from below the snout looks as if it has been fitted with a moustache. No other shark on the South African coast has it, and it is the one feature that makes a beach-caught "grey dogfish" identifiable at a glance.

The rest of the animal is a compact, stocky houndshark. The snout is short and bluntly rounded, the eyes small and oval with a nictitating membrane, the spiracles tiny. The mouth is short and arched, and inside it the teeth are not blades or hooks but low, rounded plates arranged as a pavement, the same design a smooth-hound uses to crack crabs. The two dorsal fins are nearly equal in size, the first placed over the rear of the pectorals, and the tail has a weak lower lobe.

Colour is plain: grey to grey-brown above, cream or white below, with no spots, bars or saddles. Newborns and small juveniles carry white edges on the dorsal, anal and tail fins, which fade with growth. The sharks most often confused with it on the same beaches are the striped and spotted shysharks, such as the puffadder shyshark and the Natal shyshark, which are patterned catsharks with the dorsal fins set far back, and young smooth-hounds, which have normal nostrils and a longer, pointed snout.

How big is a flapnose houndshark?

Small. The largest specimen on record measured 102 cm (3.3 ft) total length, and the old page's "2–3 ft" is a fair description of most adults: males mature at around 75 cm and females at about 85 cm, and a shark of 90 cm is a big one. Pups are born at roughly 34 cm (13 in), a third of the adult length, which is a large newborn for so small a shark and reflects a long pregnancy for a litter of only a few.

No published weights exist. Scaling from the smooth-hounds of similar build, a 90 cm female should weigh 3–5 kg, but that is an inference, not a record, so the key facts above say so rather than invent a figure. Age is a bigger blank still: no vertebral ageing study has been done, no tag has been recovered after a known interval, and lifespan, growth rate and age at maturity are all unknown. Houndsharks of this size elsewhere live 10–20 years, and that is the most anyone can honestly say.

The size bar below sets the 102 cm maximum against a 1.8 m diver.

Where flapnose houndsharks live

The whole species fits on one map of a single coastline. It is endemic to South Africa, where it has been recorded from the coast of KwaZulu-Natal, from about the Mozambique border and St Lucia south through Durban and the South Coast, into the northern Eastern Cape as far as roughly the Kei River. That is a few hundred kilometres of subtropical shore washed by the warm Agulhas Current, with summer sea temperatures of 22–26 °C and winter lows near 18 °C. The type specimen was collected off Durban and described by George Boulenger in 1902.

Within that strip the shark keeps close to land. It lives in and just beyond the surf zone over sand, rock and the mixed ground where the two meet, the same water used by bathers and shore anglers, and it turns up in the bather-protection nets set off the KwaZulu-Natal beaches. There is no reliable deep record; the animal is a creature of the shallow shelf, and any figure of tens of metres is an upper guess rather than a measurement. Whether it ranges past the Kei River into the cooler waters of the Wild Coast and beyond is unresolved, as is the possibility of a small population across the border in southern Mozambique.

Because everything it needs is within reach of the beach, the flapnose houndshark's range and South Africa's busiest recreational coastline are the same place, which is the heart of its conservation problem.

What flapnose houndsharks eat

The pavement teeth tell the story before any stomach does. This is a shellfish specialist. The few dissected specimens and the observations of anglers agree that rock lobsters are the main prey, with crabs, mantis shrimps and prawns behind them and occasional squid taken when a shoal moves inshore. Small bony fish are probably eaten when the chance arises, but they are not what the mouth is built for.

The hunt is a slow search rather than a chase. The shark works the bottom with its snout close to the sand, and here the great nasal flap earns its keep: the flap channels water across the olfactory chambers and shields the nostrils from grit as the shark noses into rubble and weed, while the ampullae of Lorenzini detect the heartbeat of a lobster tucked into a crevice. Once a crustacean is found the jaws close on it and the flat teeth crush the shell; the pieces are swallowed together, and the shark's stomach acid does the rest.

Shore anglers targeting other species on the KwaZulu-Natal coast hook flapnose houndsharks on crustacean and squid baits, which is consistent with the diet and explains why a shark so rarely seen by scientists is familiar to fishermen. Whether feeding is mainly nocturnal, as in many small houndsharks, has not been tested.

Behaviour and adaptations

No one has followed a flapnose houndshark for more than the minutes between hooking and release, so its behaviour is read from its anatomy and from where and when it is caught. The build is that of a bottom cruiser: a stiff, stocky body, small pectorals, dorsal fins of equal size and a tail with little lower lobe, all suited to slow, steady swimming a hand's breadth above the sand rather than to sprints. Like other houndsharks it has a nictitating membrane that slides over the eye when the head is pushed into rubble.

Catch records from the KwaZulu-Natal shark nets and from tagging by the Oceanographic Research Institute in Durban suggest the species is present year-round and does not undertake the long coastal migrations of the region's larger sharks. Captures cluster in the warmer months, which may reflect breeding movements or simply more people fishing, and catches are of single animals.

Two adaptations stand out. The fused nasal flap is unique among houndsharks and, together with the crushing teeth, marks a lineage that committed long ago to feeding on hard-shelled prey in shallow, sediment-laden water. The second is its size at birth: a 34 cm pup from a mother under a metre long is a large investment per offspring, a strategy that trades numbers for survival in a surf zone full of larger predators, including the bull sharks and tiger sharks that share the same coast.

Reproduction and lifespan

The flapnose houndshark is viviparous: the embryos are nourished first by yolk and then through a yolk-sac placenta attached to the wall of the uterus, the arrangement typical of houndsharks. Litters are small, 2 to 4 pups, and gestation is estimated at 9 to 10 months from the sizes of embryos in females caught at different seasons. Pups are born at about 34 cm, fully formed and carrying the white fin edges that mark juveniles, and they appear to be dropped in the same shallow water the adults use rather than in a separate nursery.

Males mature at roughly 75 cm and females at about 85 cm. How many years that takes, how often a female breeds, and how long either sex lives are all unknown, because no ageing study has ever been done on the species; the general methods and their pitfalls are described on how long sharks live. Its relatives give a rough guide: smooth-hounds of similar size mature at 3–6 years and live 10–20, and the flapnose is unlikely to be faster.

The arithmetic matters. A female producing perhaps three pups a year at best, starting at an age she may not reach on a fished coast, has one of the lowest reproductive outputs of any shark in South African waters. That, more than any single threat, is why so small and unglamorous an animal is on the Red List.

Is the flapnose houndshark dangerous?

Not in any sense. The SharkSider database holds no incident attributed to the flapnose houndshark, and the KwaZulu-Natal Sharks Board, which has kept records of every bite on that coast for more than sixty years, has never implicated it. The teeth are flat crushing plates that cannot cut skin, the mouth is a few centimetres across, and the animal is barely longer than a bather's leg. Divers who meet one over the sand report that it simply swims off.

The one place people and this shark meet is the beach, and there the risk runs entirely the other way. A hooked flapnose houndshark thrashes and can twist a wrist, but it cannot bite, and the correct response is to unhook it in the water and let it go. The same coast does carry sharks that have hurt people; they are covered honestly on our South Africa attack page, and the practical advice is on how to survive a shark attack.

The SharkSider database has no incident attributed to this species. The database draws on the International Shark Attack File, the Global Shark Attack File and verified local reports, and is updated weekly.

Conservation status and the 2020 "rediscovery"

The IUCN Red List assessed the flapnose houndshark as Vulnerable in 2018 (published 2019). The reasoning is geography as much as numbers: a species whose whole population lives in the surf zone of a few hundred kilometres of coast, and which produces two to four pups a year, is exposed to everything that happens on that coast. It is caught by shore anglers, in the prawn trawl fishery off the Tugela Bank, and in the bather-protection gill nets and drumlines the Sharks Board sets off swimming beaches, where it drowns. Trends are unknown because no survey targets it.

It is not listed under CITES or the Convention on Migratory Species and has no specific protection in South African law, though it benefits from the general recreational bag limit on sharks and from marine protected areas along its range, including iSimangaliso, Aliwal Shoal and the Pondoland MPA. Keeping bycatch records and releasing net-caught animals alive are the practical measures, and the broader context is on why sharks are endangered.

One correction is owed. The old version of this page repeated a claim from the television series Extinct or Alive that the species had not been recorded between 1902 and 2020, when the programme caught and tagged one. That is not true. Flapnose houndsharks were logged in the Sharks Board nets, in fishery surveys and by anglers throughout the twentieth century, and the Oceanographic Research Institute had tagged them before the cameras arrived. It is a rare, poorly known shark, not a lost one.

Similar species and close relatives

Scylliogaleus contains only this species, and its nearest relatives within the houndshark family are the crab-eating smooth-hounds of the genus Mustelus, which share its pavement teeth and its yolk-sac placenta. The common smooth-hound is the one that overlaps its range and is most often caught beside it; the spotless smooth-hound and the spotted estuary smooth-hound are Pacific cousins built on the same plan. Further out in the family sit the tope, which also swims South African waters, with its cutting teeth and fast body, and the whiskery shark of Australia, whose nasal barbels are a different solution to the same problem of feeding by touch and smell on the bottom.

The houndsharks most like it in shape and habit live on other continents: the banded houndshark of Japan and the spotted houndshark of Peru and Chile, both stocky inshore crustacean-feeders, and the bigeye houndshark of the Red Sea and Arabian coasts. Compare their nostrils with the flapnose's and the uniqueness of that single fused flap is obvious.

• Common Smooth-Houndspecies profile
• Tope Sharkspecies profile
• Whiskery Sharkspecies profile
• Banded Houndsharkspecies profile
• Spotted Houndsharkspecies profile
• Bigeye Houndsharkspecies profile

Written and reviewed by

SharkSider Editorial Team

A small team focused on researching sharks and making marine biology easy to understand. Every page is reviewed against current species records and the SharkSider attack database, and updated when new incidents or research appear.

Published October 14, 2022 · Last updated September 22, 2026 · No incident attributed to this species in the SharkSider attack database, which is updated weekly.