SMALLTOOTH SANDTIGER OR BUMPYTAIL RAGGEDTOOTH

A shark closely related to the Threshers

The Smalltooth Sandtiger or Bumpytail Raggedtooth (Odontaspis ferox) is a species of shark belonging to the family Odontaspididae. It has a patchy but worldwide distribution in tropical and warm temperate waters. They typically inhabit deepwater rocky habitats, though they are occasionally encountered in shallow water. They are often mistaken for the other two sharks belonging to this family. Check out more in our academy. They are a rare and vulnerable shark with populations dwindling.

 

Family: Odontaspididae – Sandtiger Sharks

Genus: Odontaspis 

Species: ferox

Taxonomy:

Phylum– Chordata

Class– Chondrichthyles

OrderLamniformes

Common NameMackerel Sharks

Family– Odontaspididae

Common NameSandtiger Sharks

GenusOdontaspis

Speciesferox

Status: IUCN Red List VULNERABLE

Average Size and Length: They are born greater than 105 cm/3.4 feet. Mature males have been measured at 275 cm/9 feet. Mature females have been measured at 364 cm/11.9 feet. The maximum recorded has been greater than 410 cm/13.5 feet.

Average Weight: The maximum recorded weight has been around 637 pounds.

Current Rare Mythical Sightings: The epithet ferox is Latin for “fierce”. The Smalltooth Sandtiger or Bumpytail Raggedtooth was originally described as Squalus ferox by Italian-French naturalist Antoine Risso in 1810, based on a specimen from Nice, France. In 1950, Gilbert Percy Whitley described O. herbsti from Australian specimens, separating them from O. ferox on the basis of dentition and the absence of spots. Leonard Compagno synonymized the two species in 1984, as subsequently discovered Pacific specimens had blurred Whitley’s distinguishing characters.

Other common names for this shark include Herbst’s Nurse shark.

Fossil teeth belonging to the Smalltooth Sandtiger have been found from Lower Pliocene from 5.3 to 3.6 million years ago (Mya) in deposits in Italy and Venezuela.

Teeth and Jaw: The mouth is large and filled with projecting teeth. The dentition of the Smalltooth Sandtiger is less robust and lacks specialized cutting and crushing teeth, suggesting that it tends to tackle smaller prey than the Sand Tiger shark. Each tooth has a narrow, tall central cusp flanked by two or three pairs of lateral cusplets. More than likely, there are around 48–56 tooth rows are in the upper jaw and 36–46 tooth rows are in the lower jaw. The front large teeth in the upper jaw are separated from the lateral teeth by two to five intermediate teeth.

Head: The Smalltooth Sandtiger differs from the Sand Tiger shark (Carcharias Taurus) in a long, conical snout and fairly large eyes. The eyes of the Sand Tiger shark are slit-like. There are no nictitating membranes.

Denticles: The dermal denticles are overlapping. They have 3 ridges and terminate on a point.

Tail: The caudal fin is strongly asymmetrical with the upper lobe much longer than the lower.

Demographic, Distribution, Habitat, Environment and Range: The Smalltooth Sandtiger or Bumpytail Raggedtooth may be found worldwide in temperate and tropical deep water. In the eastern Atlantic Ocean, it is known from the Bay of Biscay south to Morocco, including the Mediterranean Sea, the Azores, and the Canary Islands. In the western Atlantic, it has been reported from off North Carolina and Florida, the Yucatan Peninsula (Mexico), and Fernando de Noronha (Brazil). It occurs throughout the Indian Ocean, from South Africa, Madagascar, and Tanzania in the west to the Maldives and the Southwest Indian Ridge in the east. In the northern Pacific, it is known from off Japan, Hawaii, California, and Colombia, and in the southern Pacific it is known from New Caledonia, eastern Australia, and New Zealand. In New Zealand, this species can be found off the coasts of the Bay of Plenty, New Plymouth, and Hawkes Bay. The Smalltooth Sandtiger has also been filmed near Raoul Island.

They can be found on or near the bottom on the continental and insular shelves, and upper slopes between 43-1,378 feet. They are possibly epipelagic, inhabiting 459-591 feet around submarine ridges and mountains. They are sometimes seen near coral reef drop-offs, gullies and rocky reefs. In the Mediterranean they have been found at depths less than 820 feet, and even depths accessible to divers. With a few recorded exceptions, juveniles are found in deep water. The preferred temperature range is typically 43–63 °F. In hot climates, they are found below the thermocline in cooler water.

Catch records suggest this species may cover long distances in oceanic waters along underwater ridges. At a location called “Shark Point” off Beirut, Lebanon, small groups of Smalltooth Sandtigers appear every summer on rocky reefs at a depth of 100–150 feet. The same individuals have been documented returning to this site year after year. The reasons why are not confirmed, but could be related to mating. (Martin, R. Aidan. “Biology of the Bumpytail Ragged-Tooth Shark (Odontaspis ferox)“. elasmo-research.org. ReefQuest Centre for Shark Research.)

Diet: They prey on small bony fish, squid and shrimp. The largest known prey item taken was a 4.3-foot Kitefin shark (Dalatias licha), found inside the stomach of a 9.5-foot male from New Caledonia.

Adult Smalltooth Sandtiger sharks have no known predators, though they are bitten by Cookiecutter sharks (Isistius brasiliensis).

Aesthetic Identification: The Smalltooth Sandtiger differs from the Sand Tiger shark (Carcharias Taurus) in that the first dorsal fin is closer to the pectoral fin bases than the pelvic fins and a larger second dorsal and anal fin. The fins are broad-based and angular in shape. The body is bulky. They are grey or grey-brown above and lighter ventrally with darker spots.

Juveniles are uniform in color with darker fin margins, while adults often exhibit dark spots or blotches that vary widely in pattern, size, and density. Coloration also appears to vary by region, with some individuals from the Mediterranean displaying a patchy, “piebald” pattern. (Fergusson, I. K.; Graham, K. J. & Compagno, L. J. V. (2008). “Distribution, abundance and biology of the smalltooth sandtiger shark Odontaspis ferox (Risso, 1810) (Lamniformes: Odontaspididae)“. Environmental Biology of Fishes. 81 (2): 207–228.)

Biology and Reproduction: Their reproduction is poorly known. They are presumed viviparous or ovoviviparous, and the pups nourished by oophagy. The litter size is unknown.

Males mature at a length of 6.6–8.2 feet and females at a length of 9.4–11.5 feet.

A phylogenetic study based on mitochondrial DNA, performed by Naylor et al. in 1997, suggests that the Smalltooth Sandtiger and its relative, the Bigeye Sandtiger (O. noronhai), are more closely related to the Thresher sharks than to the Sand Tiger shark, to which it has a strong resemblance. If true, this would indicate that the similarities between this species and the Sand Tiger shark could have ascended as the result of convergent evolution. (Naylor, G. J. P.; Martin, A. P.; Mattison, E. G. & Brown, W. M. (1997). “Interrelationships of lamniform sharks: testing phylogenetic hypotheses with sequence data“. In Kocher, T. D. & Stepien, C. A. (eds.). Molecular Systematics of Fishes. San Diego: Academic Press. pp. 199–218)

It has a very large, oily liver, which allows it to maintain neutral buoyancy in the water column with minimal effort.

A known parasite is the tapeworm (Lithobothrium gracile), which infests the shark’s spiral valve intestine.

The carcass of a 12.1-foot-long female found off Fuerteventura in the Canary Islands contained a number of Snubnosed eels (Simenchelys parasitica) inside her heart, body cavity, and back muscles. Whether the eels contributed to the shark’s death is unknown. (Fergusson, I. K.; Graham, K. J. & Compagno, L. J. V. (2008). “Distribution, abundance and biology of the smalltooth sandtiger shark Odontaspis ferox (Risso, 1810) (Lamniformes: Odontaspididae)“. Environmental Biology of Fishes. 81 (2): 207–228)

Behavioral Traits, Sensing and Intelligence: The Smalltooth Sandtiger or Bumpytail Raggedtooth is an active offshore swimmer that has been reported alone and in small groups near gullies and reefs.

One notes that when confronted, they have been observed to stall, gape their mouths, turn around, and shake their tails towards the perceived threat. This is not confirmed though.

Faint scars seen on some individuals may be related to courtship.

Smalltooth Sandtiger Shark Future and Conservation: They are rare and vulnerable and their populations are declining. Human activity is a concern for the status of the population of this species. They are taken as bycatch in gillnets and bottom trawls, and on longlines; most captures occur in the Mediterranean and off Japan. It is usually discarded when caught, except in Japan, where the meat is consumed. Their meat isn’t as valuable as the Sand Tiger shark meat. Liver oil, the fins, jaws, and cartilage are also of value.

Populations of the Smalltooth Sandtiger in the Mediterranean are also believed to have declined, due to a combination of habitat degradation, overfishing, pollution, and human disturbance.

It has been assessed as vulnerable in Australian waters and has been protected by the Australian government since 1984, due to a decline over 50% in catches off New South Wales since the 1970s. In June 2018, the New Zealand Department of Conservation classified the Smalltooth Sandtiger as “At Risk – Naturally Uncommon” with the qualifier “Threatened Overseas” under the New Zealand Threat Classification System. Despite being protected, law enforcement proves difficult to enforce.

Smalltooth Sandtiger Shark Recorded Attacks on Humans: They are docile and harmless. They typically do not react aggressively, even when closely approached. They may defend themselves if needed.