1228 Sharks Euprotomicrus bispinatus (Quoy and Gaimard, 1824) En - Pygmy shark; Fr - Squale pygmée; Sp - Tollo pigmeo. Maximum total length about 27 cm. Occurs at or near the surface at night and apparently descends to below 400 m (possibly as deep as 1 800 m) during the day. Feeds on squid, bony fishes, and crustaceans. Without interest to fisheries. Oceanic and circumglobal in the tropical and temperate oceans. ? ? Isistius brasiliensis (Quoy and Gaimard, 1824) En - Cookiecutter shark; Fr - Squalelet féroce; Sp - Tollo cigarro. Maximum total length about 50 cm. Makes diurnal vertical migrations probably from below 1 000 m in the day to or near the surface at night. Feeds on free-living deep-water prey, but is also a facultative ectoparasite on larger marine organisms. Minor importance to fisheries in the area. Widespread oceanic in temperate and tropical oceans. Scymnodon squamulosus (Günther, 1877) En - Velvet dogfish; Fr - Squale-grogneur velouté; Sp - Bruja terciopelo. Maximum total length at least 84 cm. Demersal or pelagic near continental slopes and seamounts in depths of 550 to 2 000 m. Without interest to fisheries. Western Atlantic (Gulf of Mexico, Surinam, Brazil), eastern Atlantic from Iceland to Senegal, southern Africa and the western Pacific from Japan, South China Sea, Australia, and New Zealand. Squalidae 1229 Squaliolus aliae Teng, 1959 En - Smalleye pigmy shark. Maximum total length about 22 cm.Together with the following species possibly the smallest living shark. Epipelagic or mesopelagic near continental and island land masses; makes diurnal migrations probably from within 200 m of the surface at night down to about 2 000 m during the day. Feeds on cephalopods and small bony fish. Without interest to fisheries. Western Pacific from Japan to Australia. (after Last and Stevens, 1994) Squaliolus laticaudus Smith and Radcliffe, 1912 En - Spined pygmy shark; Fr - Squale nain; Sp - Tollo pigmeo espinudo. Maximum total length about 25 cm. Epipelagic near continental and island land masses, usually over the slopes at depths of 200 to 500 m. Feeds on deep-water squid and bony fish. Without interest to fisheries. Oceanic and nearly circumtropical. Squalus japonicus Ishikawa, 1908 En - Japanese spurdog; Fr - Aiguillat togari; Sp - Galludo japones. Maximum total length about 91 cm. On the outer continental and insular shelves and uppermost slopes at depths of 150 to 300 m, presumably on or near bottom. Interest to fisheries unknown. Southeastern Japan to the East China Sea, including Korea and the Philippines. 1230 Sharks Squalus megalops (Macleay, 1881) En - Shortnose spurdog; Fr - Aiquillat nez court; Sp - Galludo ñato. Maximum total length about 71 cm. On the outer continental shelves and slopes on or near the bottom at depths of 50 to 730 m. Schooling; feeds on bony fish, also on cephalopods, crustaceans and other elasmobranchs. Taken in bottom trawls, and by hook-and-line (sports catches); consumed fresh, dried salted, or smoked. Eastern Atlantic from Guinea to South Africa, in the Pacific from South Africa to Mozambique, from Japan to (possibly) Viet Nam and off Australia, and possibly New Caledonia and Vanuatu. Possibly a species complex. Western North Pacific representatives often recognized as Squalus brevirostris. ? ? Squalus melanurus Fourmanoir and Rivaton, 1979 En - Blacktailed spurdog; Fr - Aiguillat à queue noire; Sp - Galludo cola negra. Maximum total length 75 cm (adult females). Occurs on the insular slopes of New Caledonia, at depths of 320 to 340 m. Feeds on lanternfishes, boarfishes, barracudinas, and flatheads. Without interest to fisheries at present. Known only from New Caledonia, from the Ad and Bulari passes. Squalus mitsukurii Jordan and Snyder, 1903 En - Shortspine spurdog; Fr - Aiguillat épinette; Sp - Galludo espinilla. Maximum total length about 1.1 m; commonly to about 76 cm. On the continental and insular slopes and shelves and upper slopes at depths from 50 to 740 m. Feeds on bony fishes, cephalopods, and crustaceans. Caught in bottom trawls, but without importance to fisheries in the area. Considered to be widely distributed in temperate and subtropical parts of most oceans but possibly consisting of a species complex. Squalidae 1231 Squalus rancureli Fourmanoir and Rivanton, 1979 En - Cyrano spurdog; Fr - Aiguillat cyrano; Sp - Galludo cirann. Maximum total length at least 77 cm. Occurs on the insular slopes of Vanuatu, at depths of 320 and 400 m. Without interest to fisheries at present. Known only from the vicinity of Vate, Vanuatu. Squalus sp. A [Last and Stevens, 1994] En - Bartail spurdog. Maximum total length at least 62 cm. Known only from a few specimens collected off Queensland between Cairns and Rockhampton in 220 to 450 m. Interest to fisheries unknown. (after Last and Stevens, 1994) Squalus sp. B [Last and Stevens, 1994] En - Eastern highfin spurdog. Maximum total length at least 65 cm.On the upper continental slopes in depths to 240 to 450 cm.Biology almost entirely unknown. Interest to fisheries unknown. Eastern Australia from the Queensland Plateau to Byron Bay. A similar and probably identical spurdog occurs off northern Papua New Guinea. 1232 Sharks Squalus sp. F [Last and Stevens, 1994] En - Eastern longnose spurdog. Maximum total length about 64 cm. On the continental slope off Queensland between Cape York and Rockhampton in depths from 220 to 500 m. A similar small, long-nosed spurdog occurs off north and eastern Luzon, Philippines, from coastal waters less than a depth of 40 m to 385 m. Interest to fisheries limited. The Philippines spurdog is fished locally. click for next page click for previous page Pristiophoridae 1233 PRISTIOPHORIDAE Saw sharks by L.J.V. Compagno iagnostic characters: Small sharks with cylindrical to somewhat depressed bodies, without lateral Dridges but tail with long lateral folds reaching caudal fin; precaudal tail about as long as trunk. Head not expanded laterally, considerably depressed; 5 or 6 small gill slits present, all in front of pectoral-fin origins, their upper ends not expanded onto upper surface of head; no gill sieves or complex rakers on internal gill slits; spiracles present and very large, behind eyes; nostrils without barbels, nasoral grooves or circumnarial grooves, far anterior to mouth; eyes dorsal on head, without nictitating eyelids; snout extremely long, depressed and blade-like, with lateral teeth and unique rostral barbels in front of nostrils; mouth small, short, transversely arched, and well behind eyes; labial furrows very short, confined to mouth corners; teeth small, not blade-like, with a single low cusp, similar in upper and lower jaws and weakly differentiated along the jaws. Two dorsal fins, without spines, the first dorsal fin moderately large, high and angular, much shorter than caudal fin, and with its base nearly equidistant between pectoral- and pelvic-fin bases; second dorsal fin about as large as first; anal fin absent; caudal fin strongly asymmetrical, much less than 1/2 of total length, without a rippled or undulated dorsal margin but with a strong subterminal notch; lower lobe not present or very short; vertebral axis of caudal fin slightly raised above body axis. Caudal peduncle depressed, without precaudal pits but with low lateral folds continuing from precaudal tail. Intestinal valve of spiral type. Colour: uniform or mottled grey, brown or yellowish above, lighter below, fins dusky. rostral saw no anal fin barbels nostrils ventral view of head teeth intestinal valve of spiral type Habitat, biology, and fisheries: These are moderately abundant, primarily deep-water sharks, found on the outer continental shelves and upper slopes down to 915 m, sometimes inshore in shallow water. All species are ovoviviparous. They probably use their rostral saws to injure and kill small fishes and crustaceans, much as do the batoid sawfishes (Pristidae). They have a disjunct distribution at present from the western Pacific, western Indian Ocean, and western North Atlantic, but were formerly almost worldwide. Saw sharks are taken in bottom trawls, and are used fresh for human consumption, but are only of minor importance to fisheries in the area.Considerable fisheries exist in southern Australia, but also in the western North Pacific. Harmless sharks, not exceeding 1.4 m total length. Similar families occurring in the area No other sharks have a rostral saw with barbels. Sawfishes (Pristidae, a family of batoid fishes) are (or formerly were) common in the area and also have a rostral saw, but differ from the sawsharks in having the pectoral fins expanded anteriorly over the gill openings and fused to the sides of the head, so that the head and pectoral fins form a gill slits ventral distinct pectoral disc with the gill openings ventral (as in other teeth larger batoids); additionally, the trunk is shorter and more depressed, the first dorsal fin is partially or entirely above the pelvic-fin bases, the rostral saw has relatively few, uniformly large, continuously growing teeth (small, varying in size along the rostrum, and not growing, but periodically replaced no barbels in Pristiophoridae) and no barbels. Furthermore, the species Pristidae (sawfishes) of sawfishes are much larger, reaching 6 m or more. 1234 Sharks Key to the species of Pristiophoridae occurring in thea area 1a. Barbels closer to rostral tip than mouth or approximately equidistant, prebarbel snout 45 to 51% of preoral snout; spiracles moderately large, width less than 0.5 of eye diameter; distance from nostrils to mouth more than 1.3 times internarial space; colour uniform pale yellowish brown above; maximum total length 80 cm, males mature at 62 cm (Australia) .................................Pristiophorussp. B 1b. Barbels slightly closer to mouth than rostral tip, prebarbel snout 51 to 55% of preoral snout. Spiracles large, width almost 0.75 of eye diameter; distance from nostrils to mouth about 1.1 to 1.2 times internarial space; colour uniform dark brown above; maximum total length at least 73 cm (females) (Philippines) .................Pristiophorussp.
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