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SQUAL Dal 1
1983
FAO SPECIES IDENTIFICATION SHEETS
FAMILY: SQUALIDAE FISHING AREA 51 (W. Indian Ocean)
Dalatias licha (Bonnaterre, 1788)
OTHER SCIENTIFIC NAMES STILL IN USE: Scymnorhinus licha (Bonnaterre, 1788)
VERNACULAR NAMES: FAO : En - Kitefin shark Fr - Squale liche Sp - Carocho NATIONAL:
DISTINCTIVE CHARACTERS:
A small to moderately large shark of cylindrical body; dermal denticles of back low, sessile, with short, pointed cusps and longitudinal ridges; eyes moderately large; snout rounded and conical, about as long as mouth width; lips very thick and fringed with transverse pleats and grooves; teeth differing in upper and lower jaws, uppers much smaller,not bladelike, with slender, erect to semi-oblique, needlelike cusps and no cusplets; lowers very large, bladelike, with a single, very broad, high, erect or semi-erect cusp, no cusplets, a shallow to deep outer notch and serrations. No spines on dorsal fins; first dorsal closer to pectorals than to pelvics, its origin posterior to inner corners of pectorals; second dorsal slightly larger than first: pectoral fins considerably shorter than upper caudal margin; caudal fin with subterminal notch strongly developed, its lower lobe very weak or undeveloped. Caudal peduncle without dermal keels or precaudal pits.
Colour: a uniform dark grey or chocolate brown, rear edges of fins light.
underside of head fringed lips upper and lower dermal denticles teeth on symphyses DISTINGUISHING CHARACTERS OF SIMILAR SPECIES OCCURRING IN THE AREA:
The combination of characters underlined above readily separates this shark from all other squalids known in the area.
SIZE:
Maximum: possibly to 192 cm, most adults between 100 and 150 cm.
GEOGRAPHICAL DISTRIBUTION AND BEHAVIOUR:
In the area, off South Africa and southern Mozambique, but likely more wide-ranging. Elsewhere, in the Western North Atlantic, Eastern Atlantic from the North Sea to Cameroon, the Western Pacific from Japan, New Zealand and Australia, and the Central Pacific from the Hawaiian Islands. A common bottom and midwater shark at the depths of 250 to 450 m in the area, but elsewhere ranging from 37 to 1 100 m. Ovoviviparous, number of young 3 to 16, size at birth about 30 cm. Found in schools or groups usually of one sex. A powerful predator with exceptionally strong jaws that feeds on a wide variety of small to moderately large bottom and midwater bony fishes; also squids and octopi and on other sharks and skates.
PRESENT FISHING GROUNDS:
Offshore.
CATCHES, FISHING GEAR AND FORMS OF UTILIZATION:
Separate statistics are not reported for this species. Caught in bottom trawls. Utilized for fishmeal. SQUAL Dean 2
1983
FAO SPECIES IDENTIFICATION SHEETS
FAMILY: SQUALIDAE FISHING AREA 51 (W. Indian Ocean)
Deania quadrispinosum (McCulloch, 1915)
OTHER SCIENTIFIC NAMES STILL IN USE: None
VERNACULAR NAMES: FAO: En - Longsnout dogfish Fr - Squale-savate à long nez Sp - Tollo trompalarga
NATIONAL:
DISTINCTIVE CHARACTERS:
Body moderately stout and compressed; dermal denticles of back with high crowns and cusps resembling small pitchforks. Snout extremely long, more so than distance from mouth to origin of pectoral fins; upper labial grooves moderately long, the distance between their anterior ends equal to or greater than their lengths (taken from their anterior ends to mouth angles); teeth unlike in upper and lower jaws, uppers smaller, broad and bladelike but with elongated, erect cusps and no cusplets; lowers much larger, bladelike, broad and unser- rated, with erect or oblique cusps (more erect in adult males than adult females or juveniles of both sexes), no cusplets, and a deeply notched outer edge. A moderately large spine on first dorsal fin, and a much larger one on second dorsal, both spines with grooves; first dorsal fin moderately high, about the underside of head height of second dorsal or less, length from spine origin to free rear tip less than distance from rear tip to origin of second dorsal spine, first dorsal fin origin over or in front of rear tips of pectoral fins; pectoral fins short, with angular inner corners; caudal fin with a well-developed subterminal notch and a weak lower lobe. Caudal peduncle without dermal keels or precaudal pits.
Colour: dark brown above, paler below.
teeth at centre dermal denticle of jaws DISTINGUISHING CHARACTERS OF SIMILAR SPECIES OCCURRING IN THE AREA:
Deania profundorum: a smaller species closely resembling D. quadrispinosum and occurring in the area higher off Natal, South Africa, also elsewhere in the Eastern and Western North Atlantic and Western Pacific. It differs in having a low keel on the underside of the caudal peduncle (absent in D. quadrispinosum). keel Deania calcea: apparently not recorded from the D. profundorum area, but reported to the southwest off the Cape coast of South Africa, and wideranging in the Eastern Atlantic, Western Pacific, and southeastern Pacific. Differs in its longer, low first dorsal fin, with the distance from the lower spine origin to its free rear tip equal to or greater than distance from its free rear tip to spine origin of second dorsal fin. No other members of the family Squalidae in the D. calcea area show the combination of pitchfork-shaped denticles on the back and an extremely long snout (longer than the distance from mouth to pectoral origins).
SIZE:
Maximum: adults to about 114 cm. D. quadrispinosum
GEOGRAPHICAL DISTRIBUTION AND BEHAVIOUR:
In the area it occurs off South Africa and southern Mozambique. Elsewhere, west along the Cape coast of South Africa to Namibia, and off southern Australia.
A little-known deepwater shark, occurring on the outer continental shelves and upper slopes at depths of 150 to 732 m. Presumably ovoviviparous, though young have not been recorded. Feeds on small bony fishes.
PRESENT FISHING GROUNDS:
Uncertain.
CATCHES, FISHING GEAR AND FORMS OF UTILIZATION:
Separate statistics are not reported for this species. Taken in bottom trawls. Mode of utilization not recorded. SQUAL Squal 4 1983
FAO SPECIES IDENTIFICATION SHEETS
FAMILY : SQUALIDAE FISHING AREA 51 (W. Indian Ocean)
Squalus megalops (Macleay, 1861)
OTHER SCIENTIFIC NAMES STILL IN USE : Squalus acutipinnis Reqan, 1908
VERNACULAR NAMES: FAO: En - Shortnose spurdog Fr - Aiguillat nez court Sp - Galludo ñato
NATIONAL
DISTINCTIVE CHARACTERS:
Body moderately elongated and fusiforrn; denticles of back with slender, lanceolate crowns and a single cusp in adults. Snout pointed and slightly longer than mouth width, the distance from its tip to inner edge of nostril about equal to that from latter point to anterior end of upper labial groove; nostrils with elongated anterior flaps having short accessory lobes on their medial edges; teeth alike in both jaws, small, compressed, and with a single, strongly oblique cusp, a notched outer edge, and no cusplets or serrations. First dorsal fin larger and higher than second, its origin over inner margins of pectoral fins, close to pectoral fin insertions: a strong, moderately long un moved spine on both dorsal fins; first dorsal spine rather long, over inner margins of pectoral fins, its tip falling just below the fin apex; second dorsal spine longer and reaching above fin apex: pectoral fins rather broad, their inner corners usually acutely pointed and their posterior margins deeply concave: caudal fin asymmetrical, without a subterminal notch but with a strong ventral lobe. Caudal peduncle with a low lateral keel on each side and an upper precaudal pit.
Colour: dark brown or grey above, cream-white below; no white spots on sides.
DISTINGUISHING CHARACTERS OF SIMILAR SPECIES OCCURRING IN THE AREA:
Squalus acanthias Linnaeus, 1758: a cold and tem- perate water species currently not known from the area but. found to the southwest, off the Cape coast of South Africa west to Namibia, and widespread elsewhere; might keel occur in the extreme southwest of the area in deep water. S. acanthias Differs from other species of Squalus in the following character combination: no accessory lobes on anterior nasal flaps; origin of first dorsal fin over or posterior to inner corners of pectorals; fin spines shorter, the first posterior to inner corners of pectoral fins; pectoral fins narrow and falcate; second dorsal fin smaller than first; S. acanthias S. megalops precaudal pits present; ventral caudal fin lobe strong; and usually white spots on sides. left nostril Squalus asper: snout broader and more blunt, origin of first dorsal fin over or behind pectoral rear tips; first dorsal spine longer, with origin behind pectoral rear tips; second dorsal fin as large as first; pectoral fins not falcate; ventral caudal fin lobe shorter; upper precaudal pit absent; dermal denticles of back with broad crowns and three cusps; size larger, to at least 114 cm. S. asper Squalus cf. mitsukurri: denticles of sides broad and 3-cusped; distance from snout tip to inner edge of nostril greater than that from nostril to anterior end of upper labial furrow; pectoral fins with narrowly rounded inner corners and shallowly concave to nearly straight posterior margins. Other species of Squalidae: fin spines grooved or absent; usually caudal fin with a subterminal notch, no S. cf. mitsukurii precaudal pits.
pointed S. megalops concave
S. Cf. mitsukurii S. asper S. megalops dermal denticle
SIZE:
Maximum: about 71 cm, most adults between 40 and 70 cm.
GEOGRAPHICAL DISTRIBUTION AND BEHAVIOUR: S. cf. mitsukurii S. megalops In the area, found off South Africa and southern underside of head Mozambique. but probably more widespread. Elsewhere, in the tropical and temperate Eastern Atlantic from Guinea to Namibia. and Western Pacific.
An offshore schooling shark found at moderate depths in the area from 50 to 450 m, where it is extremely common; elsewhere down to 732 m. Ovovivi- parous, number of fetuses in a litter 2 to 4, size at birth between 18 and 24 cm. Feeds primarily on bony fishes. also on cephalopods, crustaceans. and other elasmobranchs.
PRESENT FISHING GROUNDS:
Probably offshore.
CATCHES, FISHING GEAR AND FORMS OF UTILIZATION:
Separate statistics are not reported for this species.
Commonly taken in bottom trawls, and by hook and line (sports catches). Minimally utilized for human consumption.
SQUAL Squal 5 1983 FAO SPECIES IDENTIFICATION SHEETS
FAMILY: SQUALIDAE FISHING AREA 51 (W. Indian Ocean)
Squalus asper Merrett, 1973
OTHER SCIENTIFIC NAMES STILL IN USE: None
VERNACULAR NAMES: FAO: En - Roughskin spurdog Fr - Aiguillat à peau rugneuse Sp - Galludo raspa
NATIONAL:
DISTINCTIVE CHARACTERS:
Body moderately stout and fusiform; denticles of back with broad crowns, with 3 cusps in adults. Snout bluntly pointed, slightly greater than or equal to mouth width, the distance from its tip to inner edge of nostril about equal to that from latter point to anterior end of upper labial furrow; anterior flaps of nostrils with strong accessory lobes on their medial edges; teeth alike in both jaws, small, compressed, and with a single, strongly oblique cusp, a notched outer edge, and no cusplets or serrations. First dorsal fin about as large as underside of head second, its origin over or posterior to inner corners of pectorals; both dorsal fins with a very strong, long ungrooved spine; first dorsal fin spine long, its origin well posterior to inner corners of pectoral fins, its tip reaching fin apex; second dorsal spine long, reaching fin apex; pectoral fins broad, their inner corners broadly rounded and their posterior margins straight or nearly so; caudal fin asymmetri- cal, without a subterminal notch and with a short ventral lobe. Caudal pecuncle with a low lateral keel on each side but without an upper precaudal pit. Colour: dark brown above, lighter below; fins with prominent white posterior edges; no white spots on sides.
upper teeth and lower teeth DISTINGUISHING CHARACTERS OF SIMILAR SPECIES OCCURRING IN THE AREA:
Other species of Squalus: snout more pointed, origin of first dorsal fin over or anterior to pectoral insertions, first dorsal fin spine shorter, with origin over pectoral inner margins, second dorsal fin noticably smaller than first, pectoral fins more falcate, with posterior edges more or less concave and inner corners narrowly rounded to pointed, a more prominent ventral caudal lobe, and an S. megalops upper precaudal pit. Other species of Squalidae: fin spines grooved, or spines absent, usually a subterminal notch on caudal fin.
SIZE:
Maximum: about 118 cm. S. asper
GEOGRAPHICAL DISTRIBUTION AND BEHAVIOUR:
In the area, from the Aldabra Island group, South Africa, and southern Mozambique, but likely more wide- ranging. Elsewhere from the Western North Atlantic and Central Pacific. A little-known dogfish of the upper continental slopes and outermost shelves, from depths of 214 to 600 m. Ovoviviparous, number of fetuses 21 or 22; size at birth near 25 to 28 cm. Feeds on bony fishes and squid.
PRESENT FISHING GROUNDS:
Uncertain.
CATCHES, FISHING GEAR AND FORMS OF UTILIZATION:
Separate statistics are not reported for this species. Probably taken in bottom trawls. Mode of utilization uncertain.
SQUAL Squal 6 1983 FAO SPECIES IDENTIFICATION SHEETS
FAMILY: SQUALIDAE FISHING AREA 51 (W. Indian Ocean)
Squalus cf. mitsukurii Jordan & Snyder, 1903)
OTHER SCIENTIFIC NAMES STILL IN USE: Squalus "fernandinus" not of Molina, 1782, in part; often misidentified as Squalus blainvillei (Risso, 1826)
VERNACULAR NAMES: FAO: En - Shortspine spurdog Fr - Aiguillat épinette Sp - Galludo espinilla
NATIONAL:
DISTINCTIVE CHARACTERS:
Body moderately elongated and fusiform; denticles of back with broad crowns and 3 cusps in adults. Snout pointed, slightly longer than mouth width, the distance from its tip to inner edge of nostril greater than that from latter pint to anterior end of upper labial groove: nostrils with elongated anterior flaps having short accessory lobes on their medial edges; teeth alike in both jaws, small, compressed, and with a single, strongly oblique cusp, a notched outer edge, and no cusplets or serrations; first dorsal fin larger and higher than second, its origin over inner margins of pectoral fins, close to pectoral fin insertions; a strong, moderately long, ungrooved spine on both dorsal fins, underside of head generally not reaching their apices; base of first dorsal spine over inner margins of pectoral fins; pectoral fins rather broad, their inner corners narrowly rounded and their posterior margins nearly straight; caudal fin asymmetrical, without a subterminal notch but with a strong ventral lobe. Caudal peduncle with a low lateral keel or, each side and an upper precaudal pit. Colour: back more cm less dark brown, belly whitish.
nostril DISTINGUISHING CHARACTERS OF SIMILAR SPECIES OCCURRING IN THE AREA:
Squalus megalops: differs in having slender, lanceo- late denticles on back in adults, a shorter snout (distance from snout tip to inner edge of nostril about equal to that from latter point to anterior end of upper labial groove), dermal denticle pectoral fins with deeply concave posterior margins and acutely pointed inner corners (but they may be straighter, and with bluntly pointed inner corners in large adults). Squalus asper: snout broader and blunt; origin of first dorsal fin over or behind pectoral fin rear tips; first dorsal spine longer, with origin behind pectoral rear tips; second dorsal fin as large as first; pectoral fins not falcate; ventral caudal fin lobe shorter; upper precaudal pit absent, dermal denticles of back with broad crowns underside of head and 3 cusps; size larger, to at least 114 cm. Squalus blainvillei (Risso, 1826); currently not S. megalops S. cf. mitsukurii known from the area, but apparently wide-ranging (Eastern Atlantic and Western Pacific) and to be expected. Confused with the species in the Western Indian Ocean here provisionally referred to as S. mitsu- kurii, but differing in its higher first dorsal fin (height pointed about equal to the fin base length versus about 2/3 of fin S. megalops height in S. cf. mitsukurii) and longer fin spines that concave usually reach or extend above the dorsal fin apices. Other species of Squalidae: fin spines grooved or equal absent, usually a subterminal notch on caudal fin, and no precaudal pits. nearly straight
SIZE: S. asper
Maximum: to at least 95 cm.
GEOGRAPHICAL DISTRIBUTION AND BEHAVIOUR:
In the area, off South Africa, southern Mozambique, S. blainvillei Zanzibar, northern Madagascar, possibly also southern India. Elsewhere, S. mitsukurii is definitely found in the Western North Pacific off Japan, Korea, China and pro- bably Taiwan Island arid Vietnam, also or, seamounts in the North Pacific; very similar dogfish species, possibly iden- tical to S. mitsukurii also occur in the Eastern Atlantic, arid the Western South, Central and Eastern Pacific. A common temperate and tropical offshore shark ranging in S. cf. mitsukurii depth from 50 to 740 m. Ovoviviparous, number of fetuses 4 to 9; size at birth 22 to 26 cm. Feeds on bony fishes, cephalopods and crustaceans.
PRESENT FISHING GROUNDS:
Offshore.
CATCHES, FISHING GEAR AND FORMS OF UTILIZATION:
Separate statistics are not reported for this species. Caught in bottom trawls. Little utilized in the area.
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