A small shark with hook-like teeth

The Hooktooth dogfish (Aculeola nigra) is a species of shark belonging to the family Etmopteridae. It is the only member of its genus, and can be found in a limited range from Peru to Chile.


Family: Etmopteridae – Lantern Sharks

Genus: Aculeola 

Species: nigra


Phylum– Chordata

Class– Chondrichthyles



Common NameDogfish Sharks

Family– Etmopteridae

Common NameLantern Sharks




Average Size and Length: The Hooktooth dogfish is born between 13-14 cm. Mature males are between 1.4-1.5 feet on average and mature females 1.7-1.8 feet. The maximum recorded has been 60 cm or 2 feet.

Current Rare Mythical Sightings: The holotype is held at the National Natural History Museum, Santiago, Chile; a female caught at a depth of 360 feet.

Teeth and Jaw: The lips of the Hooktooth dogfish are thin. The mouth is long, arched and broad with small hook-like teeth in both the upper and lower jaws. They are narrow with slender, erect cusps typically without cusplets and no blades. There are about 60 rows of teeth in either jaw.

Head: The snout of the Hooktooth dogfish is broad and blunt. It has very large eyes that are much closer to the tip of the snout than the first gill slit. There are short anterior nasal flaps.

Denticles: The dermal denticles are erect and narrow and have conical ridged cusps with stellate bases.

Tail: There is a long upper caudal lobe and the lower caudal lobe is not differentiated. It is broad asymmetrical and not paddle-shaped. The subterminal notch is present but weak. There are no lateral keels on the caudal peduncle.

Demographic, Distribution, Habitat, Environment and Range: The Hooktooth dogfish can be found in the eastern Pacific from Peru to Chile. They are considered epibenthic and possibly benthic, and are found over continental shelves and upper slopes between 360-2,411 feet.

Diet: Their diet is unknown but more than likely small bony fish and invertebrates are a part of it.

Aesthetic Identification: The Hooktooth dogfish is blackish brown in color, and has a stalky build. The gill openings are large. The dorsal fin spines are short and grooved and much lower than the low dorsal fins. The first dorsal fin originates over the pectoral inner margins. The second dorsal fin is larger than the first, and originates opposite or slightly behind the pelvic origins. There are rounded free rear pectoral fin tips and short inner margins. This shark lacks a luminous gland.

Biology and Reproduction: They are ovoviviparous having at least 3 pups per litter.

Behavioral Traits, Sensing and Intelligence: Unknown.

Hooktooth Dogfish Future and Conservation: There is not enough data to evaluate but they are common throughout their limited range. They are possibly caught as bycatch.

Hooktooth Dogfish Recorded Attacks on Humans: Not a threat to humans.