Genus: Aculeola De Buen, 1959a, Bol.Mus.Nac.Hist.Nat.Santiago, Chile, 27(3):180.

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1 click for previous page Aculeola De Buen,1959 SQUAL Acul Genus: Aculeola De Buen, 1959a, Bol.Mus.Nac.Hist.Nat.Santiago, Chile, 27(3):180. Type Species : Aculeola nigra De Buen, 1959, by original designation. Synonymy : None. Remarks : This monotypic genus is close to Centroscyllium but is clearly distinct, in anatomical characters (including jaw, cranial, and vertebral characters) as well as in external morphology. Aculeola nigra De Buen, 1959 SQUAL Acul 1 Aculeola nigra De Buen, 1959a, Bol.Mus.Nac.Hist.Nat.Santiago, Chile, 27(3):180. Holotype : Estacion de Biologia Marina de Montemar, Chile, No. EBMCh , apparently lost, 488 mm female. Type Locality: Off Concon, Chile, 110 m depth. Synonymy : None. FAO Names: En - Hocktooth dogfish; Fr - Squale noir; Sp - Tollo negro de cochos. Diagnostic Features: Head with very short anterior nasal flaps; flaps not expanded as barbels; snout short, flattened and.truncated, length much less than distance from mouth to pectoral origins and about 1/4 length of head; gill openings moderately large, increasing in width posteriorly; lips thin, not pleated or auctorial; teeth alike in both jaws, not bladelike, with a narrow, hooked, slender erect cusp, usually no cusplets, and no blades; about 60 rows of teeth in either jaw. Small grooved finspines present on both dorsal fins; first dorsal origin over pectoral inner margins, insertion well in front of pelvic origins and about midway between pectoral and pelvic bases; second dorsal origin about opposite or slightly behind pelvic origins, second dorsal slightly larger than first, with second dorsal base less than twice length of first dorsal base; pectoral fins with rounded free rear tips and short inner margins, not greatly expanded and narrowly pointed or broadly lobate; caudal fin asymmetrical, not paddle-shaped, upper lobe long, lower lobe not differentiated, subterminal notch present and weak. Caudal peduncle without lateral keels, or precaudal pits. Dermal denticles with erect, narrow, conical ridged cusps and stellate bases. Cloaca without a luminous gland. Colour: blackish. Geographical Distribution : Eastern Pacific: Peru to central Chile. Habitat and Biology : A little-known, benthic and epibenthic shark of the Pacific south American continental shelf and upper slope, at depths of 110 to 560 mm. Ovoviviparous, number of young at least 3. Feeding habits unknown but probably small fishes and invertebrates. A relatively common species in its limited range. Size : Maximum total length about 60 cm, size at birth probably about 13 or 14 cm (size of full-term fetuses), females mature between 52 and 54 cm and reach 60 cm, males mature at 42 to 46 cm. Interest to Fisheries : None.

2 Centrophorus Müller & Henle, 1837 SQUAL Centr Genus : Centrophorus Müller & Henle, 1837, Ber.K.Preuss.Akad.Wiss.Berl., 2:115. Type Species: Squalus granulosus Bloch & Schroeder, 1801, by monotypy. Synonymy: Genus Lepidorhinus Bonaparte, 1838; Genus Entoxychirus Gill, 1862; Genus Entoxychyrus Dumeril, 1865 (error?); Genus Machephilus Johnson, 1867; Genus Atractophorus Gilchrist, 1922; Genus Actractophorus Gilchrist, 1922 (error?); Subgenus Gaboa Whitley, 1940 (Genus Centrophorus); Subgenus Somnispinax Whitley, 1940 (Genus Centrophorus); Subgenus Somnisphinax Neave, 1950 error for Somnispinax); Genus Enchiridiodon Smith, Nomen Nudum : Centrophorus squaloideus Engelhardt, Field Marks: Grey or grey-brawn, huge green eyes, moderate-sized snout, spines on both dorsals, broad, bladelike upper and lower teeth without cusplets, lower teeth much larger than uppers, pectoral free rear tips angular to attenuated, caudal with strong subterminal notch. Diagnostic Features: Head with short, anterior nasal flaps; flaps not expanded as barbels; snout flattened, broadly parabolic to slightly pointed, length less than distance from mouth to pectoral origins and half length of head or less; gill openings moderately broad, about equally wide or increasing slightly in width posteriorly; lips thin, not pleated or suctorial; teeth differing in upper and lower jaws, compressed, bladelike and interlocking in both jaws but much larger in the lower jaw; teeth of both jaws with a single cusp and variably developed distal blade but no cusplets, cusps of upper teeth erect to oblique, lower cusps oblique, crowns of teeth in both jaws rather broad and low, edges often serrated; tooth rows 31 to 42/27 to 35. Rather large, grooved, strong finspines present on both dorsal fins; first dorsal origin over pectoral insertions or inner margins, insertion well in front of pelvic origins and about equidistant between pectoral and pelvic bases or slightly closer to the pectoral bases; second dorsal origin varying from over last third of pelvic bases to slightly posterior to pelvic free rear tips; second dorsal smaller than first, its base about half to 3/4 length of first dorsal base; pectoral fins with free rear tips varying from squared-off and angular to elongated and acutely pointed, not broadly lobate; caudal fin asymmetrical, not paddle-shaped, upper lobe long, lower lobe poorly differentiated to short and welldeveloped, subterminal notch present and strong. No precaudal pits or lateral keels on caudal peduncle. Dermal denticles with low, flat ridged crowns, varying from leaf-shaped and pediculate, with posterior cusps, to cusplets, block-shaped, and without pedicels. Cloaca without a luminous gland. Colour: light to dark grey or grey-brown above, often lighter below. Remarks : The arrangement of this genus follows the revisions of Bigelow & Schroeder (1957), Garrick (1959), Cadenat (1959a,b), and Bass, d'aubrey & Kistnasamy (1976), pending further work by S. Springer (in prep.). I follow Bigelow & Schroeder (1957), Cadenat (1959) and Bass, d'aubrey & Kistnasamy (1976) in synonymizing Atractophorus (a genus proposed and used for juvenile Centrophorus specimens with barbs on their finspines which apparently are lost in adults) with Centrophorus, Bass, d'aubrey & Kistnasamy (1976) in synonymizing Enchiridiodon with Centrophorus, and various writers in including Lepidorhinus in Centrophorus. The current key and arrangement of species is highly tentative and probably will require considerable revision when new information is published. Particularly troublesome are the species of Centrophorus with sessile, block-like denticles, which vary considerably in denticle characters with growth. An alternative arrangement of some of these species is provided by Cadenat & Blache (1981), who list granulosus, lusitanicus, and uyato as 'formes' of Centrophorus, in recognition of the taxonomic difficulties provided especially by juveniles of the species. They provide a key to eastern Atlantic Centrophorus which accesses C. granulosus at three different places and C. uyato at two places to separate large adults, small adults and subadults, and juveniles of these species from each other and from other species. 1a. Lateral trunk denticles with leaflike flattened crowns on elevated narrow to broad pedicels extending above the denticle bases, and with medial and lateral cusps on their posterior ends 2a. Free rear tips of pectoral fins broadly angular and not reaching past first dorsal spine origin. Denticles of adults with multiple lateral cusps... C. squamosus 2b. Free rear tips expanded into narrow angular lobes that reach past first dorsal spine origin. Denticles of adults with a pair of lateral cusps... C. acus 1b. Lateral trunk denticles with flat sessile atop the denticle bases, without separate pedicels and with or without a posterior medial. cusp

3 - 36-3a. Second dorsal fin very small, half height of first dorsal or less, with spine origin usually well posterior to rear tips. Inner margins of pectoral fin longer than distance from second dorsal spine origin to upper caudal origin C. moluccensis 3b. Second dorsal fin larger, 3/4 of first dorsal height or more, with spine origin usually over pelvic inner margins. Inner margins of pectoral about as long or shorter than distance from second dorsal spine origin to upper caudal origin. 42. Denticles of adults without cusps, crowns broadly rounded posteriorly 5a. Distance from first dorsal insertion to origin of second dorsal spine about as long as tip of snout to pectoral insertions... C. granulosus 5b. Distance from first dorsal insertion to origin of second dorsal spine about as long as tip of snout to pectoral origins C. tesselatus 4b. Denticles of adults with medial cusps, crowns angular and thornlike posteriorly 6a. Snout rather short and broad, preoral length less than mouth width. Free rear tips of pectoral fins slightly elongated, not extending behind first dorsal spines. Lateral trunk denticles of adults narrow and teardropshaped. Postventral margin of caudal fin virtually straight in adults. A large species reaching over 1.5 m... C. niaukang 6b. Snout rather long and narrow, preoral length greater than mouth width. Free rear tips of pectoral fins greatly elongated, extending well behind first dorsal spine. Lateral trunk denticles of adults broad and rhomboidal. Postventral margin of caudal fin notched in adults. Maximum size usually below 1 m...c. uyato C. harrisoni Centrophorus acus Garman, 1906 SQUAL Centr 5 Centrophorus acus Garman, 1906, Bull.Mus.Comp.Zool.Harvard, 46(11):204. Comparative Zoology, Harvard, MCZ Type Locality : Japan. Holotype : Museum of Synonymy : Centrophorus steindachneri Pietschmann, 1907;?Centrophorus drygalskii Engelhardt, FAO Names : En - Needle dogfish; Fr - Squale-chagrin aiguille; Sp - Quelvacho aguón. Field Marks : No anal fin, two dorsal fins with large spines, bladelike unicuspidate teeth in upper and lower jaws, with lowers much larger than uppers, a moderately long snout, leafshaped tricuspidate, semi-imbricated lateral denticles, and rear tips of pectoral fins narrowly angular and strongly extended. Diagnostic Features: Snout moderately long, narrowly parabolic, preoral snout somewhat greater than mouth width but shorter than distance from mouth to pectoral origins; upper anterolateral teeth with erect to semioblique cusps. First dorsal fin relatively low and long; second dorsal moderately large, as high as first, with base about 3/4 length of first dorsal base, and spine origin over inner margins of pelvic fins; distance from first dorsal insertion to origin of second dorsal spine about as upper and lower teeth

4 long as tip of snout to pectoral midbases in adults; free rear tips of pectoral fins formed into a narrow, angular but only moderately elongated lobe that reaches the level of first dorsal spine, inner margins slightly shorter than distance from second dorsal spine to caudal origin. Caudal fin with shallowly concave or weakly notched postventral margin in adults. Lateral trunk denticles partly overlapping each other, with thick pedicels elevating flat, leaflike crowns, a strong main cusp and a pair of lateral cusps on their posterior edges in adults. Geographical Distribution: Western North Pacific: Japan (southeastern Honshu). Western North Atlantic: Gulf of Mexico. Habitat and Biology : A little-known deepwater dogfish of the western Pacific and western North Atlantic, probably found below 200 m depth. Size : Mature males to at least 81 cm (holotype). Interest to Fisheries : None? Literature : Garman (1913); Bigelow & Schroeder (1957); Compagno & Vergara (1978); S. Springer (pers. comm.). Centrophorus granulosus (Bloch & Schneider,1801) SQUAL Centr 1 Squalus granulosus Bloch & Schneider, 1801, Syst.Ichthyol.:135. Holotype : Apparently lost. Type Locality : None given in original account. Synonymy :? Centrophorus bragancae Regan, 1906;? Centraphorus atromarginatus Garman, 1913;? Centrophorus machenquensis Maul, FAO Names : En - Gulper shark; Fr - Squale-chagrin commun; Sp - Quelvacho. dermal denticles upper and lower teeth Field Marks : No anal fin, two dorsal fins with large spines, bladelike unicuspidate teeth in upper and lower jaws, with lowers much larger than uppers, a moderately long and broad snout, fairly short first dorsal fin and high second dorsal, blocklike, very broad, sessile-crowned, wide-spaced, acuspidate lateral denticles, and rear tips of pectoral fins narrowly angular and strongly extended. Diagnostic Features : Snout moderately long, broadly parabolic, preoral snout subequal or somewhat greater than mouth width but shorter than distance from mouth to pectoral origins; upper anterolateral teeth with erect to semioblique cusps. First dorsal fin moderately high and short, second dorsal moderately large, nearly as high as first, with base about 3/4 length of first dorsal base, and spine origin over inner margins of pelvic fins; distance from first dorsal insertion to origin of second dorsal spine about as long as tip of snout to pectoral insertions in adults and subadults; free rear tips of pectoral fins formed into narrow, angular and elongated lobes that reach well beyond the level of first dorsal spine, inner margins longer than distance from second dorsal spine to caudal origin; caudal fin with 'a shallowly notched posterior margin in adults and subadults. Lateral trunk denticles not overlapping each other, blocklike, with crowns sessile on bases and without pedicels, crowns broad and transversely rhomboidal in adults, without cusps on their posterior edges.

5 Geographical Distribution: Western North Atlantic: Northern Gulf of Mexico. Eastern Atlantic: France, Portugal, Madeira to Mediterranean, Canaries, Senegal, Ivory Coast, Nigeria, Cameroon to Zaire. Western Indian Ocean: Aldabra Island. Western Pacific: Japan (southeastern Honshu). Habitat and Biology : A large fairly common deepwater dogfish of the outer continental shelves and upper slopes, usually on or near the bottom at depths from 100 to 1200 m, but commonest below 200 m. Ovoviviparous. Eats hake, epigonids and lanternfish. Size : Maximum total length at least 150 cm, young are born from 30 to 42 cm or more. Interest to Fisheries : Primarily fished in the eastern Atlantic with bottom trawls, but also caught on hook-and-line and with pelagic trawls. Smoked and dried salted for human consumption; also processed for fishmeal and liver oil. Potentially valuable for its large liver, with high squalene content in the liver oil. The Japanese representative of the species is fished for liver oil. Literature : Bigelow & Schroeder (1957), Cadenat (1957); Compagno (1981); Cadenat & Blache (1981). Remarks : The Japanese C. atromarginatus Garman, 1913 is often recognized as a valid species, but I tentatively include it in C. granulosus following Bigelow & Schroeder (1957), who compared the holotype of C. atromarginatus with Atlantic specimens and accounts of C. granulosus and could find no specific differences except possibly longer gill openings in the Atlantic material I do agree with these writers that the separation of these species"...remains an open question" (Bigelow & Schroeder, 1957). The validity of C. machequensis and C. braganzae are uncertain also; these species are listed under C. granulosus as a present expedient only. Centrophorus harrissoni McCulloch, 1915 SQUAL Centr 6 Centrophorus harrissoni McCulloch, 1915, Zool.Result.Fish.Exp.Endeavour, Commonw.Australia, Dept.Trade Cust., 3:99, pl. 14, fig Holotype :? number, 760 mm female. Type Locality : Near Cabo Island, Victoria, Australia. Synonymy :? Centrophorus armatus barbatus Teng, FAO Names: En - Dumb gulper shark; Fr - Squale-chagrin bilimélé; Sp - Quelvacho galludo. Diagnostic Features : Very similar to C. uyato and possibly not distinct; said to differ in its partially serrated lower teeth, but serrations on the lower teeth are a variable feature in Centrophorus.

6 Geographical Distribution : Western Pacific:? Taiwan Island, Australia. Habitat and Biology : A little-known deepwater dogfish of the continental and insular slopes at 250 to 384 m. Size: Maximum reported 80 cm. Interest to Fisheries : None? Literature : Whitley (1940); Fowler (1941); Bigelow & Schroeder (1957); Teng (1962). Remarks : C. harrissoni is very close to C. uyato and may be a junior synonym of that species. C. armatus barbatus Teng, 1962, is apparently not conspecific with Atractophorus armatus Gilchrist, 1922 (= C. moluccensis, but may instead be based on a juvenile (with barbed dorsal spines of C. harrissoni or C. uyato C. harrissani itself is very close to C. uyato, and may be a junior synonym of that species. Centrophorus lusitanicus Bocage & Capello, SQUAL Centr 2 Centrophorus lusitanicus Bocage & Capello, 3864, Proc.Zool.Soc.Lond., 24:260, fig. 1. Holotype : A possible syntype in British Museum Natural History), BMNH , 75 cm immature male; other type material probably lost. Type Locality : Portugal, Atlantic Ocean. Synonymy :? Centrophorus ferrugineus Chu et at., FAO Names : En - Lowfin gulper shark; Fr - Squale-chagrin à longue dorsate; Sp - Quelvacho lusitánico. Field Marks: No anal fin, two dorsal fins with large spines, bladelike unicuspidate teeth in upper and lower jaws, with lowers much larger than uppers, a moderately long and broad snout, very long first dorsal fin and high second dorsal, blocklike, sessile-crowned, wide-spaced, cuspidate lateral denticles, and rear tips of pectoral fins narrowly angular and strongly extended. Diagnostic Features: Snout moderately long, broadly parabolic, preoral snout equal or dermal denticles somewhat greater than mouth width but shorter than distance from mouth to pectoral origins; upper anterolateral teeth with semioblique or oblique cusps. First dorsal fin very low and long; second dorsal moderately large, nearly as high or slightly higher than first, with base about 1/2 to 3/5 length of first dorsal base, and spine origin over inner margins of pelvic fins; distance from first dorsal insertion to origin of second dorsal spine about as long as tip of snout to pectoral midbases in adults and subadults; free rear tips of pectoral fins formed into narrow, angular and elongated lobes that reach well beyond the level of first dorsal spine, inner margins slightly shorter than distance from second dorsal spine to caudal origin; caudal fin with a shallowly concave to weakly notched posterior margin in adults and subadults. Lateral trunk denticles not overlapping each other, blocklike, with crowns sessile on bases and without pedicels, crowns elongated and longitudinally rhomboidal in adults, with a strong main cusp and no lateral cusps on their posterior edges in adults. click for next page