Literature : Bigelow & Schroeder (1957); Bass, d'aubrey & Kistnasamy (1976); Cadenat & Blache (1981); S. Springer (pers. comm.).

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1 click for previous page Geographical Distribution : Western North Atlantic: Gulf of Mexico. Eastern Atlantic: western Mediterranean and Gibraltar to Senegal, Ivory Coast to Nigeria, Cameroon to Angola, northern Namibia. Indian Ocean: southern Mozambique,? India.? Western North Pacific: Taiwan Island. Habitat and Biology : A common deepwater dogfish of the outer continental shelves and upper slopes, on or near the bottom, in depths from 50 to 1400 m and commonest below 200 m. Ovoviviparous, number of young usually only one. Feeds on bony fishes and squid. Size : Maximum total length about 100 cm, males mature between about 81 and 94 cm, mature females from 75 to 89 cm, size at birth between 40 and 50 cm. Interest to Fisheries : Known fisheries primarily in the eastern Atlantic, where this species is taken with bottom trawls, line gear, fixed bottom nets and pelagic trawls. It is utilized dried salted for human consumption; probably also for fishmeal and liver oil. Its liver oil is potentially valuable for its high squalene content. Literature : Bigelow & Schroeder (1957); Bass, d'aubrey & Kistnasamy (1976); Cadenat & Blache (1981); S. Springer (pers. comm.). Remarks : Centrophorus harrissoni may not be distinct- from this small, long-nosed species. C. uyato is difficult to distinguish from the larger C. granulosus when immature or subadult (see Cadenat & Blache, 1981 for a detailed account of this problem), but adults apparently can be separated by their considerably smaller size, longer and narrower snout, retention of a cusp on their blocklike lateral denticles, usually more oblique-cusped upper teeth, and often a darker mouth lining. Centroscyllium Müller & Henle, 1841 SQUAL Centro Genus : Centroscyllium Müller & Henle, 1841, Syst.Beschr.Plagiost.Suppl.:191. Type Species : Centroscyllium fabricii Reinhardt, 1825 Müller & Henle, 1841, by monotypy, equals Spinax fabricii Synonymy : Genus Paracentroscyllium Alcock, Field Marks : Greyish or blackish-brown, no anal fin, well-developed dorsal fin spines, short to moderately long snout, comblike teeth with cusps and cusplets in both jaws. Diagnostic Features: Anterior nasal flaps short,not expanded as barbels; snout flattened, truncatedparabolic to slightly pointed, short to moderately long, length less than distance from mouth to pectoral origins and less than half length of head; gill opening small to moderately broad about equally wide or increasing very slightly in width posteriorly; lips thin, not pleated or suctorial; teeth alike in upper and lower jaws, with slender cusps and prominent cusplets not bladelike; tooth rows 45 to 68 in either jaw. Strong, grooved finspines present on both dorsal fins, the second dorsal spine strikingly larger than the first; first dorsal origin over or somewhat behind pectoral inner margins, insertion well in front of pelvic origins but varying from closer to the pectoral bases to closer to the pelvic bases; second dorsal origin varying from over first half of pelvic bases to about over pelvic free rear tips; second dorsal larger than first, its base less than twice length of first dorsal base; pectoral fins with short, broadly rounded free rear tips and inner margins, not broadly lobate or acute and attenuated; caudal fin asymmetrical, not paddle-shaped, upper lobe long, lower lobe weakly differentiated, subterminal notch present and strong. Caudal peduncle without precaudal pits or lateral keels. Dermal denticles with slender, acute, erect, narrow ridged cusps and stellate bases. Cloaca without a luminous gland. Colour greyish to blackish brown above and below.

2 Remarks : Bigelow & Schroeder (1957) recognized five species of this poorly known genus, C. fabricii, C. granulatum, C. nigrum, C. ornatum, and C. ritteri, to which Abe (1966) added a sixth new species, C. kamoharai Recently Nakaya in Okamura et al., 1982 reported that there were two species of Centroscyllium from the Kyushu-Palau Ridge near Japan, which could not be placed in existing species. At least one of these species a slender, Etmopterus-like, long-nosed shark, is almost certainly new, and the other, a very heavy-bodied, shortnosed species, may very well be new also. The following account of the genus and key to species is highly provisional: Key to Species: 1a. Colour grey-brown above, with striking black markings on undersides of head, abdomen, and pectoral fins, and sides of tail... C. ritteri 1b. Colour blackish or blackish-brown above and below, without black markings on underside of body or sides of tail 2a. Rear tips of pectoral fins ending well anterior to origin of first dorsal spine. Distance between pectoral and pelvic bases much greater than head length 3a. Caudal peduncle elongated, distance from second dorsal insertion to upper caudal origin somewhat longer than distance from eye to pectoral origins. A dwarf species, adult at less than 30 cm long... C. granulatum 3b. Caudal peduncle rather short, distance from second dorsal origin to upper caudal origin as long as distance from eye to third gill slits or less. Size larger, adult at over 40 cm long 4a. Mouth long and more narrowly arched. Denticles close-set on body. A large species, adult at over 50 cm long... C. fabricii 4b. Mouth short and more broadly arched. Denticles few and wide-spaced, skin of body almost naked. A smaller species, adult between 40 and 50 cm... C. kamoharai 2b. Rear tips of pectoral fins ending about opposite origin of first dorsal spine or slightly in front of it. Distance between pectoral and pelvic bases about equal to head length or less 5a. Fins with white tips. Mouth fairly short, less than a third as high as wide... C. nigrum 5b. Fins without white tips. Mouth fairly long, almost half as high as wide... C. ornatum Centroscyllium fabricii (Reinhardt, 1825) SQUAL Centro 1 Spinax fabricii Reinhardt, 1825, Overs.K.danske Vidensk.Selsk.Forh., ( ):3. Holotype : One syntype, Universitetets Zoologiske Museum, Copenhagen, ZMUC 185. Type Locality : Julianehaab, West Greenland.

3 FAO Names : En - Black dogfish; Fr - Aiguillat noir; Sp - Tollo negro merga. Field Marks : No anal fin, grooved dorsal fin spines, teeth with narrow cusps and cusplets in upper and lower jaws. Colour uniformly blackish-brown without white markings, abdomen long, caudal peduncle short. Diagnostic Features : Body moderately stout and compressed. Preoral snout moderately long, about 2/3 of distance from centre of mouth to pectoral origins; mouth moderately arched, about a third as long as wide. Second dorsal fin considerably larger than first; pectoral apices when laid back ending well anterior to first dorsal spine origin. Caudal peduncle short, distance from second dorsal insertion to upper caudal origin about as long as distance from eye to first gill slits. Lateral trunk denticles close-set, conical and with hooked cusps. Colour blackish brown above and below, without conspicuous black markings on ventral surface or sides of tail; fins without white markings. Size large, adults to possibly a metre. upper and lower teeth Geographical Distribution : Western North Atlantic: S. Baffin Island and Greenland to Virginia (USA) and possibly Gulf of Mexico. Eastern Atlantic: Iceland along Atlantic slope to Senegal, Guinea to Sierra Leone, Namibia and the southwestern Cape coast of South Africa. Habitat and Biology : An abundant deepwater schooling shark of the outermost continental shelves and upper slopes at depth mostly below 275 m and ranging from 180 m to about 1600 m; at high latitudes, it may move up to near the surface, especially during the winter and when darkest. At the northern extremes of its range this species does not range into truely Arctic waters but occurs on their fringe in the boreal North Atlantic. Water temperatures at the bottom where these sharks are most commonly caught are 3.5 to 4.5 C, but sometimes down to 1 C. There is some evidence of segregation by sex and size within populations and of movements of schools into shallower water and increase in school size during winter and spring. This species is ovoviviparous, with embryos to at least 14 cm. This shark has luminescent organs scattered in its skin, but apparently not arranged in regular arrays like other species. Food organisms reported include pelagic crustaceans, cephalopods, and jellyfish; presumably small deepwater fishes are also eaten. Size : Maximum total length at least 84 cm, may reach 107 cm; adult females reported at 58 to 70 cm. Interest to Fisheries : Abundant in the North Atlantic and commonly taken by bottom trawls and with line gear, but apparently little utilized. Literature : Bigelow & Schroeder (1948, 1957); Templeman (1963); Krefft & Stehmann (1973); Cadenat & Blache (1981). Remarks : Records of this species from tropical west Africa and southwestern Africa need confirmation.

4 Centroscyllium granulatum Gϋnther, 1887 SQUAL Centro 2 Centroscyllium granulatum Gϋnther, 1887, Rep.Sci.Res.Voy.H.M.S."Challenger", Zool. 22:7. Holotype: British Museum Natural History 3, BMNH , 265 mm 11 inches or 279 mm, in original account) adult male. Type Locality : Port Stanley, Falkland Islands, 448 m depth. FAO Names : En - Granular dogfish; Fr - Aiguillat râpe; So - Tollo negro raspa. Field Marks: No anal fin, grooved dorsal fin spines, teeth with narrow cusps and cusplets in upper and lower jaws, uniformly brownish-black coloration without conspicuous markings, long abdomen, long caudal peduncle and dwarf size. Diagnostic Features : Body moderately stout and compressed. Preoral snout moderately long, about 3/5 of distance from mouth to pectoral origins; mouth rather narrowly arched, nearly half as long as wide. Second dorsal fin much larger than first; pectoral apices when laid back ending well anterior to first dorsal spine origin. Caudal peduncle elongated, distance from second dorsal insertion to upper caudal origin about as long as distance from eye to pectoral origins. Lateral trunk denticles close-set, conical and with hooked cusps. Colour brownishblack above and below, without conspicuous black areas on underside of body or caudal peduncle; fins plain. Size small, adults below 30 cm. Geographical Distribution : Western South Atlantic: Falkland Islands/ Malvinas. Habitat and Biology : A poorly known deepwater shark caught off the Falkland Islands slope at 448 m. Size : Maximum total length at least 28 cm (adult male holotype). Interest to Fisheries: None. Literature : Bigelow & Schroeder (1957); Cadenat & Blache (1981). Remarks : This species has been confused with Etmopterus granulosus (Günther, 1880) but is quite distinct (Krefft, 1968a). The writer examined the holotypes of both species in the British Museum (Natural History), and was able to confirm the validity of this species. Centroscyllium kamoharai Abe, 1966 SQUAL Centro 3 Centroscyllium kamoharai Abe, 1966, Jap.J.Ichthyol., 13(416):190, figs 1-8. Holotype Zoological Institute, Faculty of Science, University of Tokyo no , 440 mm adult female. Type Locality: Suruga Bay, off Yaizu, Honshu, Japan. FAO Names : En - Bareskin dogfish; Fr - Aiguillat lisse; Sp - Tollo negro liso.

5 Field Marks : No anal fin, grooved dorsal fin spines, teeth with narrow cusps and cusplets in upper and lower jaws, uniform dark coloration except for white-tipped fins, long abdomen and short caudal peduncle, wide-spaced denticles on body. Diagnostic Features: Body stout and compressed. Preoral snout moderately long, about 3/5 of distance from mouth to pectoral origins; mouth extremely short and very broadly arched, less than a third as long as wide. Second dorsal fin slightly larger than first; pectoral apices when laid back fall well anterior to first dorsal spine origin. Caudal peduncle short, distance from second dorsal insertion to upper caudal origin about as long as distance from eye to third gill slits. Lateral trunk denticles widespaced and sparse on body, which is almost naked, conical and with hooked cusps. Colour uniform blackish. Size moderate, adults to about 44 cm. Geographical Distribution : Western North Pacific: Japan (southeastern Honshu). Habitat and Biology : not reported. A little-known deepwater dogfish, depth Size : Maximum total length reported 44 cm, females mature at 42 to 44 cm, males unknown. Interest to Fisheries : None. Literature : Abe (1966). Centroscyllium nigrum Garman, 1899 SQUAL Centro 4 Centroscyllium nigrum Garman, 1899, Mem.Mus.Comp.Zool.Harv.Coll, 24:28, pl. 1, fig. 2, pls. 4-5, pl. 69, fig. 1. Holotype : Two specimens mentioned, 11 1/2 and 4 3/4 inches long, but no type designated; presumably the first of these specimens is the holotype). Type Locality : Two localities mentioned, 70 9'30"N, "W, 999 m, and 6 30'N, 81 44'W, 1016 m, both off Panama, without reference to specimens. Synonymy : Centroscyllium ruscosum Gilbert, Other Scientific Names Recently in Use : Centroscyllium granulosum (not Günther, 1880 = Etmopterus granulosus).

6 FAO Names : En - Combtooth dogfish; Fr - Aiguillat peigne; Sp - Tolio negro peine. Field Marks : No anal fin, grooved dorsal fin spines, teeth with narrow cusps and cusplets in upper and lower jaws, uniform dark coloration except for white-tipped fins, short abdomen and short caudal peduncle, close-set denticles on body. Diagnostic Features : Body moderately stout and compressed. Preoral snout moderately long, about 2/3 of distance from mouth to pectoral origins; mouth very broadly arches, less than a third as long as wide. Second dorsal fin about as large as first; pectoral apices when laid back ending just anterior to first dorsal spine origin. Caudal peduncle short, distance from second dorsal insertion to upper caudal origin about as long as distance from eye to first gill slits. Lateral trunk denticles close-set, conical and with hooked cusps. Colour blackish except for white-tipped fins, no prominent black markings on underside of body and sides of tail. Size moderate, adults to about 50 cm. Geographical Distribution : Central Pacific: Hawaiian Islands. Eastern Pacific: southern California (USA), Panama, Cocos Islands, Columbia, Ecuador, northern and central Chile, Galapagos Islands. Habitat and Biology : A little-known deepwater dogfish of the eastern Pacific and Hawaiian continental and insular slopes, on or near the bottom at depths of 400 to 1143 m. Size : Maximum total length 50 cm, males adult at 35 to 39 cm, females to at least 50 cm. Interest to Fisheries : None. In California incidentally caught in sablefish (Anoplopoma) traps, but not utilized. Literature : Bigelow & Schroeder (1957); Kato, Springer & Wagner (1967). Remarks : This species has been confused with Etmopterus granulosus (Günther, 1880), and Centroscyllium granulatum (Günther, 1887), but is quite distinct. Centroscyllium ornatum (Alcock, 1889) SQUAL Centro 5 ParacentroscyIlium ornatum Alcock, 1889, Ann.Mag.Nat.Hist., ser.6, 4:379. Syntypes : Three syntypes, Zoological Survey of India, Calcutta, ZSI and damaged, about 120 mm; and ZSI (now in British Museum (Natural History) collection). Type Locality : Bay of Bengal, Swatch of No-ground, 741 to 522 m. FAO Names : En - Ornate dogfish; Fr - Aiguillat élégant; Sp - Tollo negro elegante.

7 Field Marks : No anal fin, grooved dorsal fin spines, teeth with narrow cusps and cusplets in upper and lower jaws, uniform dark coloration, short abdomen and short caudal peduncle, close-set denticles on body. Diagnostic Features : Body moderately stout and compressed. Preoral snout moderately long, about half of distance from mouth to pectoral origins; mouth narrowly arched, nearly half as high as wide. Second dorsal fin somewhat larger than first; pectoral apices when laid back ending about opposite to first dorsal spine origin. Caudal peduncle moderately long, distance from second dorsal insertion to upper caudal origin about as long as distance from eye to third gill slits. Lateral trunk denticles close-set, conical and with hooked cusps. Colour blackish, without white fin tips or prominent black markings on underside of body and sides of tail. Size moderate, adults to about 50 cm. Geographical Distribution : Northern Indian Ocean: Arabian Sea and Bay of Bengal. Habitat and Biology : A little-known deepwater dogfish from the upper continental slopes of India near bottom at depths from 521 to 1262 m. Size : Maximum total length to 30 cm (immature?). Interest to Fisheries : None. Literature : Fowler (1941); Bigelow Schroeder (1957). & Remarks : The writer examined two of the syntypes and other material of this species in the Zoological Survey of India, Calcutta, in The illustration is a reconstruction based on the syntypes and other data. Centroscyllium ritteri Jordan & Fowler, 1903 SQUAL Centro 6 Centroscyllium ritteri Jordan & Fowler, 1903, Proc.U.S.Nat.Mus., 26(1324):635, fig. 6. Holotype : Stanford University SU-7185, 430 mm immature female. Type Locality : Misaki, Japan. click for next page