Author: (Maul, 1955)
A large, bulky shark. Head with a long, bulbously conical snout, eyes very large, without nictitating eyelids; mouth long and extending behind eyes; teeth moderately large, with prominent narrow cusps and lateral cusplets; upper anterior teeth separated from lateral teeth by one row of small intermediate teeth. First dorsal fin on back and closer to pectoral fins than pelvics;upper precaudal pit present but lateral keels absent from caudal peduncle; caudal fin asymmetrical but with a strong ventral lobe; anal fin and second dorsal fin smaller than first dorsal but broad-based. Colour: uniform dark chocolate brown, without spots.
Teeth with a single pair of lateral cusplets, root lobes moderately arched and broad; one row of small intermediate teeth between upper anterior and lateral tooth rows. First dorsal fin with its posterior margin extending vertically from its apex; origin of second dorsal fin about over first thirds of pelvic bases; anal fin low and rounded, height much less than base length; length of dorsal margin of caudal fin about 33% of total length in young. Colour: uniform chocolate brown, without spots.
Eastern South Atlantic: Southern Brazil. Eastern North Atlantic: Madeira. Western Indian Ocean: Seychelles?
Habitat and Biology:
A poorly known deepwater shark; formerly known only from the stuffed Madeira holotype, but recently collected at considerable depths off southern Brazil (V. Sadowsky, pers.comm., 1982). Apparently an inhabitant of continental and insular slopes at 600 to 1000 m depth or more. Reproduction and feeding habits unknown.
Maximum total length about 360 cm, two adult males from 326 to 342 cm long and an adult female about 326 cm (V. Sadowsky, pers.comm.).
Interest to Fisheries:
The holotype was taken on a vertical longline set by fishermen for black scabbardfish (Aphanopus carbo). Presumably taken occasionally by deepwater fisheries.
Compagno (1981a) recognized this species but suggested that it possibly was only an extreme variant of O. ferox; however, additional evidence convinced the writer that it is a valid species, readily separable from O. ferox. A set of jaws possibly from the Seychelles (D. Ward, pers. comm.) has the dentitional characters of this species, and is the basis for the Indian Ocean record of O. noronhai.
Holotype: Museu Municipal do Funchal, Madeira, NMF-2691, 1710 mm female. Type Locality: Off Camara de Lobos, Madeira, between 600 and 1600 m depth and most likely at 800 to 1000 m depth.