Author: (Bocage and Capello, 1864)
Field Marks:
Black or blackish brown coloration, no anal fin, dorsal fins with very small fin spines, very long snout, greatly elongated labial furrows that nearly encircle mouth, lanceolate upper teeth and bladelike lower teeth with moderately long, oblique cusps, fairly slender body that does not taper abruptly from pectoral region, moderately large lateral trunk denticles with partly smooth, oval, cuspidate crowns in adults and subadults.
Diagnostic Features:
Body fairly slender, not strongly tapering back from pectoral region. Snout very long, preoral length about equal to distance from mouth to pectoral origins and much greater than mouth width; lips not thick and fleshy; upper labial furrows very long, g their lengths greater than distance between their front k ends; lower teeth with moderately long, semioblique cusps and moderately high, fairly broad roots. Dorsal fins about equal in size and height, fin spines very small but with tips protruding from fins; first dorsal base expanded forwards as a prominent ridge, origin over pectoral bases; second dorsal base longer than space between it and upper caudal origin, free rear tip nearly reaching upper caudal origin; pectoral fins moderately large, apices falling well in front of first dorsal spine when laid back; free rear tips of pelvic fins extending to about opposite second dorsal insertion. Lateral trunk denticles moderately large, with anteriorly smooth but posteriorly ridged, oval, cuspidate crowns. Colour blackish brown.
Geographical Distribution:
Eastern Atlantic: Iceland, Faeroe Islands along Atlantic slope to Portugal, Senegal, Madeira, Gabon to Zaire, Namibia. Indian Ocean: Aldabra Islands, India (Travancore Coast). Western Pacific: New Zealand, Australia (New South Wales). Eastern Pacific: Northern Chile.
Habitat and Biology:
A little-known but fairly common deepwater dogfish of singular appearance, found on the upper continental slopes on or near the bottom at depths of 270 to 1070 m. Ovoviviparous, with 4 young in a litter. Eats lanternfishes.
Size:
Maximum total length about 90 cm, males mature at 64 to 68 cm, females at 82 cm.
Interest to Fisheries:
Caught in bottom trawls in the eastern Atlantic, and utilized there for fishmeal.
Remarks:
The possible synonymy of Centrophorus rossi with this species was discussed by Bigelow and Schroeder (1957) and Garrick (1959a), who preferred to recognize C. rossi because of its supposedly longer head. The writer examined the holotype of C. rossi in the Zoological Survey of India, Calcutta, ZSI F 225/1 (233 mm female possibly newborn) and found that its head length, 29.6% of total length, fell in the range reported for C. crepidater by Cadenat and Blache (1981), 21.3 to 29.7% of total length. As the specimen apparently has no other characters that distinguish it from C. crepidater, C. rossi is synonymized with C. crepidater here. The holotype of C. rossi is not the only record of this species from the Western Indian Ocean, as records of C. owstoni from the Aldabra Island group by Forster et al. (1970) were based on C. crepidater (Drs J. Bass and P.C. Heemstra, pers.comm.).
Although Cadenat and Blache (1981) recognized C. furvescens as a separate species on its slightly shorter preoral snout (10.5% of total length, vs 11.4 to 15.5% for specimens of C. crepidater), the difference is so slight and intraspecific variation in C. crepidater is sufficiently great for me to retain C. furvescens in synonymy of C. crepidater, following Kato, Springer and Wagner (1967).
Type material:
Holotype: Museu Bocage, Lisbon, Portugal, MB T112(49), lost in fire. Type Locality: Off Portugal.