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TRIAK Hypo 1
1983
FAO SPECIES IDENTIFICATION SHEETS
FAMILY: TRIAKIDAE FISHING AREA 51 (W. Indian Ocean)
Hypogaleus hyugaensis (Miyosi, 1939)
OTHER SCIENTIFIC NAMES STILL IN USE: Hypogaleus zanzibariensis (Smith, 1957) Galeorhinus (Hypogaleus) zanzibariensis Smith, 1957
VERNACULAR NAMES: FAO : En - Blacktip tope Fr - Requin-hâ élégant Sp - Cazón elegante NATIONAL:
DISTINCTIVE CHARACTERS:
A small to moderate-sized shark with an elongated body. Head flattened above and below, snout relatively long and narrowly rounded; nostrils with very small nasal flaps, not formed as barbels or greatly expanded, without nasoral grooves; 5 gill slits, the last 2 above pectoral fin bases; eyes horizontally oval on sides of head, with well- differentiated nictitating lower eyelids entirely, or almost entirely, inside the eye underside of head openings; spiracles very small; mouth angular, with moderately long labial furrows that do not reach front of mouth; teeth small, alike in both jaws, compressed, bladelike; lateral teeth with short, oblique cusps and outer cusplets only; anterior teeth more symmetrical, smaller, with both inner and outer cusplets. First dorsal fin on back between pectoral and pelvic fin bases, its origin just behind free rear tips of pectoral fins, base of fin closer to pectoral than to pelvic fin bases; second dorsal fin about 2/3 as large as first dorsal and twice as large as anal fin, its origin anterior to origin of latter; caudal fin with a strong loner lobe and a moderately long terminal lobe about 1/3 as long as upper edge of fin. Interdorsal ridge absent; caudal peduncle without keels or precaudal pits. Denticles on sides broad. strongly cuspidate and ridged, with strong side cusps in adults. Colour: grey above, white below; dorsal fins and upper caudal lobe with black tips. upper and lower teeth DISTINGUISHING CHARACTERS OF SIMILAR SPECIES OCCURRING IN THE AREA:
Mustetus species: interdorsal ridge present; den- ticles on sides with weak side cusps or none; eyes dorsolateral on head; anterior nasal flaps broader, larger; teeth not bladelike, their crowns low and rounded, form- ing a pavement; caudal fin with a weak or undeveloped lower lobe. Mustelus sp. teeth Galeorhinus galeus: a temperate-water shark occur- ring on the Cape coast of South Africa just south of the area, and rather similar to this species, but differing in its longer snout, rounded mouth, smaller second dorsal fin about as large as the anal fin but less than half the size of the first dorsal, and a much longer terminal lobe on the Galeorhinus galeus caudal fin (about half as long as upper edge of fin). lago species: smaller sharks without cusplets on their bladelike teeth, first dorsal origin over rear ends of pectoral fin bases, second dorsal fin nearly as large as first dorsal, caudal fin with lower lobe weak or hardly developed. Small species of Hemigaleidae and Carcharhinidae: caudal fin with a rippled upper edge, no precaudal pits, and no supraorbital crests on the cranium. Carcharhini- dae also with a scroll intestinal valve, and Hemigaleidae with upper teeth strongly differentiated from lowers.
SIZE: upper tooth lago omanensis Maximum: about 127 cm.
lobe GEOGRAPHICAL DISTRIBUTION AND BEHAVIOUR: precaudal pit In the area, from off South Africa, Kenya and notch Zanzibar, but probably more wide ranging. Elsewhere from the Western Pacific, off Taiwan Island and Japan.
A bottom-living shark of deepish continental waters, well developed ranging in depths in the area from 65 to 230 m, but lower lobe elsewhere up to 40 m. Viviparous, with a yolk-sac placenta, number of fetuses in a litter 11; size at birth dorsal margin near 35 cm (size of full-term fetuses). viewed from Feeds on bony fishes. above Carcharhinidae and Hemiqaleidae
PRESENT FISHING GROUNDS:
Offshore.
CATCHES, FISHING GEAR AND FORMS OF UTILIZATION:
Separate statistics are not reported for this species.
Caught in bottom trawls and on hook and line.
An uncommon species apparently little-utilized in the area.
TRIAK lago 1
1983
FAO SPECIES IDENTIFICATION SHEETS
FAMILY: TRIAKIDAE FISHING AREA 51 (W. Indian Ocean)
lago omanensis (Norman, 1939)
OTHER SCIENTIFIC NAMES STILL IN USE: Galeorhinus omanensis (Norman, 1939) Eugaleus omanensis Norman, 1939
VERNACULAR NAMES: FAO: En Bigeye houndshark Fr - Requin-hâ à gros yeux Sp - Cazón ojigrande
NATIONAL:
DISTINCTIVE CHARACTERS:
A small, rather slender shark with a stout, humpbacked trunk. Head flattened above and below, snout moderately long and narrowly rounded; nostrils with small nasal flaps, not formed as barbels or greatly expanded, without nasoral grooves; 5 gill slits, moderately long and wide-spaced, the last two above pectoral fin bases; eyes horizontally oval on sides of head, with well-differentiated nictitating lower eyelids partially inside the eye openings; spiracles small; mouth angular, with moderate-sized labial furrows that do not reach front of mouth; teeth small, alike in both jaws, compressed, bladelike; lateral teeth with short, oblique cusps but without cusplets. First dorsal fin on back close to pectoral fins, with its origin over rear ends of pectoral fin bases; second dorsal fin slightly smaller than first dorsal and over twice as large as anal fin, its origin anterior to origin of latter; caudal fin with lower lobe hardly indicated, terminal lobe moderately long and about 1/3 as long as upper edge of fin. Interdorsal ridge absent; caudal peduncle without keels or precaudal pits. Denticles on sides narrow, with a strong medial cusp and weak side cusps. Colour: grey-brown above, white or lighter below; dorsal fins and caudal upper lobe often black-tipped. DISTINGUISHING CHARACTERS OF SIMILAR SPECIES OCCURRING IN THE AREA:
Iago species: an apparently undescribed species of lago occurs in the Arabian Sea south to southern India along with I. omanensis. but differs in its shorter head and very low pectoral and dorsal fins. lago species Other species of Triakidae in the area have the origin of the first dorsal fin more posterior, over or behind the pectoral inner margins; also teeth either molariform and not bladelike, or, if bladelike, with well- developed cusplets.
Mustelus species SIZE:
Maximum: about 58 cm, adult males (at 30 or 36 cm) markedly smaller than females (at 40 to 58 cm).
GEOGRAPHICAL DISTRIBUTION AND BEHAVIOUR:
Confined to the area, from the Red Sea and the Gulf of Oman to Pakistan and southern India.
A small, deepwater shark found on the continental shelf and slope at depths from 110 to possibly 2 200 m, but probably entering shallower water. Viviparous, with a yolk-sac placenta. Feeds on small fishes and crustaceans.
PRESENT FISHING GROUNDS:
Offshore.
CATCHES, FISHING GEAR AND FORMS OF UTILIZATION:
Separate statistics are not reported for this species. Caught in floating gillnets (India). Utilized fresh for food, but of slight importance.
TRIAK Must 6 1983
FAO SPECIES IDENTIFICATION SHEETS
FAMILY: TRIAKIDAE FISHING AREA 51 (W. Indian Ocean)
Mustelus manazo Bleeker, 1854
OTHER SCIENTIFIC NAMES STILL IN USE : Mustelus palumbes Smith, 1957
VERNACULAR NAMES: FAO : En - Starspotted smoothhound Fr - Emissole étoilée Sp - Musola palomba NATIONAL:
DISTINCTIVE CHARACTERS:
A small shark. Body moderately elongated, head flattened above and below, snout relatively long and narrowly rounded, without hypercalcified rostrum; nostrils with long, broad nasal flaps that do not reach mouth; no nasoral grooves; 5 gill slits, the last 2 over pectoral fin bases; eyes horizontally oval, dorsolateral on head, with well-developed nictitatincq lower eyelids partially inside the eye openings; spiracles moderately large; mouth broadly angular; labial furrows moderately long, not reaching mouth, the uppers considerably longer than lowers: teeth small, alike in both jaws, blunt-crowned, not bladelike, without cusplets and with low cusps only in young. First dorsal fin on back between pectoral and pelvic fin bases, its origin over pectoral inner margins; second dorsal fin almost as large as first dorsal, and much larger than anal fin, its origin well in front of anal fin; caudal fin with lower lobe short in adults and hardly developed in young. An interdorsal ridge present; caudal peduncle without keels or precaudal pits. Valvular intestine with a spiral valve.
Colour: back and sides grey or grey-brown, underside cream-white; a series of small white spots on sides. DISTINGUISHING CHARACTERS OF SIMILAR SPECIES OCCURRING IN THE AREA:
Mustelus mosis: very similar to Mustelus manazo, and often mistaken for it, but dif- fering in having its upper labial furrows about as long as, or slightly longer than the lower furrows, no white spots on sides, and rostrum and other structures strongly hypercalcified (the hypercalcified rostrum can be easily exa- mined by pinching the snout or cutting into it). Scylliogaleus quecketti: snout shorter, bluntly rounded; mouth broadly arcuate; ante- rior nasal flaps greatly expanded reaching mouth, and covering broad nasoral grooves. Other superficially similar sharks: teeth not blunt, molariform and arranged in a pave- ment. a) Mustelus mosis b) Mustelus manazo b) Scylliogaleus quecketti
underside of head SIZE:
Maximum: at least 120 cm in the area, smaller elsewhere.
GEOGRAPHICAL DISTRIBUTION AND BEHAVIOUR:
In the area, definitely known from off South Africa arid southern Mozambique, but nominally recorded from virtually the entire area; records from the Red Sea eastward to southern India are apparently based on M. mosis as far as is known, although it is possible that M. manazo also occurs in this part of the area. Elsewhere, off Namibia and the Cape arid west coast of South Africa, arid the Western Pacific from southern Siberia, Korea, Japan, China, Taiwan Ialarid and Vietnam. A small, bottom-living shark found in continental waters, ranging in depth from the intertidal zone to at least 360 m depth. Ovoviviparous, without a yolk-sac placenta; size at birth about 30 cm.
PRESENT FISHING GROUNDS:
Primarily inshore.
CATCHES, FISHING GEAR AND FORMS OF UTILIZATION: Separate statistics are not reported for this species.
Caught in bottom trawls and on hook and line (sports catches). Apparently little utilized in that part of the area where it is definitely known. TRIAK Must 7
1983
FAO SPECIES IDENTIFICATION SHEETS
FAMILY: TRIAKIDAE FISHING AREA 51 (W. Indian Ocean)
Mustelus mosis Hemprich & Ehrenberg, 1899
OTHER SCIENTIFIC NAMES STILL IN USE : Mustelus manazo Bleeker, 1854 (misidentified)
VERNACULAR NAMES:
FAO : En - Arabian smoothhound Fr - Emissole d'Arabie Sp - Musola arábiga
NATIONAL:
DISTINCTIVE CHARACTERS: A small shark. Body moderately elongated, head flattened above and below, snout relatively long and narrowly rounded, with a hypercalcified rostrum that can be felt by pinching the snout or can be readily dissected out; nostrils with long, broad nasal flaps that do not reach mouth; no nasoral grooves; 5 gill slits, the last 2 over the pectoral fin bases; eyes horizontally oval, dorsolateral on head, with well-developed nictitating lower eyelids partially inside the eye openings; spiracles moderately large; mouth broadly angular; labial furrows moderately long, not reaching mouth, the uppers about as long as, or slightly longer than lowers; teeth small, alike in both jaws, blunt-crowned, not bladelike, without cusplets and with low cusps only in young. First dorsal fin on back between pectoral and pelvic fin bases, its origin over pectoral inner margins; second dorsal fin almost as large as first dorsal, and much larger than anal fin, as origin well in front of anal fin; caudal fin with lower lobe short in adults and hardly developed in young. An interdorsal ridge present; caudal peduncle without keels or precaudal pits. Valvular intestine with a spiral valve.
Colour: back and sides plain grey or grey-brown, underside cream-white; no spots on sides. DISTINGUISHING CHARACTERS OF SIMILAR SPECIES OCCURRING IN AREA: Mustelus manazo: upper labial furrows conspicuously longer than lowers; body usually with numerous small white spots: rostrum and other skeletal structures not hypercalcified. Scylliogaleus quecketti: snout shorter, bluntly rounded, mouth broadly arcuate, ante- rior nasal flaps greatly expanded, reaching mouth and covering broad nasoral grooves. Other superficially similar small sharks: teeth not blunt, molariform and arranged in pavement.
a) Mustelus manazo b) Mustelus mosis c) Scylliogaleus quecketti
SIZE: underside of head Maximum: about 106 cm; maturin at 63 to 80 cm.
GEOGRAPHICAL DISTRIBUTION AND BEHAVIOUR :
As currently known, confined to the northern part of the area, from the Red Sea, the "Gulf", Pakistan, west and southeast coast of india and Sri Lanka. It is not known if the species ranges further eastward into the eastern Indian Ocean.
A small bottom-living shark found in continental waters of the area. Viviparous, with a yolk-sak placenta, 6 to 10 young in a litter. Size at birth about 33 to 37 cm.
Probably feeds primarily on crustaceans.
PRESENT FISHING GROUNDS :
Off India, Sri Lanka and Pakistan, and probably also in the Red Sea, primarily inshore.
CATCHES, FISHING GEAR AND FORMS OF UTILIZATION: Separate statistics are not reported for this species.
Caught in bottom trawls, fixed bottom and floating gillnets, and on line gear. Utilized fresh for human consumption, probably also for fishmeal.
TRIAK Scyl 1
1983 FAO SPECIES IDENTIFICATION SHEETS
FAMILY: TRIAKIDAE FISHING AREA 51 (W. Indian Ocean)
Scylliogaleus quecketti Boulenger, 1902
OTHER SCIENTIFIC NAMES STILL IN USE: None
VERNACULAR NAMES: FAO: En - Flapnose houndshark Fr - Virli à clapet Sp - Cazón mosqueador NATIONAL:
DISTINCTIVE CHARACTERS:
A small, moderately stout shark. Head flattened above and below, snout short and broadly rounded; nostrils with greatly enlarged nasal flaps, extending posteriorly to mouth and medially to meet each other at upper symphysis, and shallow nasoral grooves; 5 gill slits, the last 2 above pectoral fin bases; eyes horizontally oval, underside of head dorsolateral on head, with well-differentiated nictitating lower eye- lids almost entirely inside the eye openings; spiracles small; mouth short and broadly rounded, with long labial grooves that reach front of mouth; teeth small, alike in both jaws, blunt, molariform, without cusps, arranged in a pavement. First dorsal fin on back, with its origin over pectoral inner margins or free rear tips and its base about equidistant between pectoral and pelvic fin bases; second dorsal fin about as large as first, over twice the size of anal fin, with its origin anterior to anal fin origin; caudal fin with a short ventral lobe in adults (poorly developed in young) and a moderately long terminal lobe about 1/3 as long as upper edge of fin. Interdorsal ridge absent; caudal peduncle without keels or precaudal pits. Denticles on sides strongly cuspidate.
Colour: grey above, cream below, no prominent markings. teeth DISTINGUISHING CHARACTERS OF SIMILAR SPECIES OCCURRING IN THE AREA:
Triakis megalopterus: found just southwest of the area, on the Cape and west coast of South Africa, resembling S. quecketti in its short, blunt snout, broadly arched mouth, and long labial furrows that reach the level of the upper jaw, but differs in having its nasal flaps not greatly expanded, no nasoral grooves, teeth cuspidate, fins larger, and often numerous darks spots on the back. Other species of Triakidae: nasal flaps not greatly expanded, no nasoral grooves.
underside of head SIZE:
Maximum: about 102 cm.
GEOGRAPHICAL DISTRIBUTION AND BEHAVIOUR:
Virtually confined to the area, off South Africa. Triakis megalopterus
An inshore, bottom-dwelling shark. Often found at the surfline. Possibly viviparous, with a yolk-sac pla- centa, number of fetuses in a litter 2 to 4; size at birth 35 cm. Feeds primarily on crustaceans, including lobsters.
PRESENT FISHING GROUNDS:
Inshore.
CATCHES, FISHING GEAR AND FORMS OF UTILIZATION:
Separate statistics are not reported for this species.
Primarily caught inshore on hook and line, probably also trawled.
Moderately common but little utilized where it occurs.
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