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4. ORDER PRISTIOPHORIFORMES - SAW SHARKS

Order Pristiophoriformes Compagno, 1973c, J.Linn.Soc.(Zool.), 53 suppl. 1.

Synonymy : Order Asterospondyli: Gill, 1893 (in part). Order Euselachii, Suborder Galei: Jordan, 1923 (in part). Order Euselachii, Suborder Squaloidei: Blot, 1969 (in part). Suborder Galei: Gill, 1872 (in part). Suborder Plagiostomi Tectospondyli: Hasse, 1879 (in part). Order Pristiophorida: Fowler, 1969. Order Pristiophorae: Smith, 1949. Order Pristiophori: Whitley, 1940. Order Pristiophoriformes: Berg & Svedovidov, 1955; Patterson, 1967; Lindberg, 1971; Rass & Lindberg, 1971; Applegate, 1974; Chu & Wen, 1979. Suborder Pristiophorina: Matsubara, 1955. Suborder Pristiophoroidea: Bigelow & Schroeder, 1948. Suborder Pristiophoroidei: Nelson, 1976. Order Squalea, Suborder Squalida: White, 1936, 1937 (in part). Suborder Squali: Gill, 1862 (in part). Order Squaliformes, Suborder Squaloidei: Berg, 1940 (in part); Arambourg & Bertin, 1958. Suborder Squaliformes: Goodrich, 1909 (in part); Bertin, 1939 (in part), Budker & Whitehead, 1971 (in part). Order and Suborder Squaloidea: Schultz & Stern, 1948 (in part). Suborder Squaloidea: Romer, 1945, 1966 (in part); Norman, 1966 (in part). "Division" Squaloidei: Regan, 1906 (in part). "Group" Squaloidei: Garman, 1913 (in part). Suborder Squaloidei: Engelhardt, 1913 (in part). Order Squatinae: Fowler, 1941 (in part).

Diagnostic Features: Trunk somewhat depressed but not greatly flattened and raylike. Head somewhat depressed but not expanded laterally; 5 or 6 pairs of gill slits present on sides of head, with the posteriormost in front of pectoral fin origins; spiracles present and very large, just behind and above level of eyes; nostrils without barbels, nasoral grooves or circumnarial grooves, separate from mouth, anterior nasal flaps short and not reaching mouth; eyes on dorsal surface of head, without nictitating lower eyelids; snout very long and greatly depressed, forming a sawlike blade with lateral denticles and a pair of long rostral barbels on its ventral surface well in front of the nostrils; mouth small, arched but short, behind eyes; labial furrows greatly reduced, at mouth cornets only; teeth weakly differentiated along the jaws, without enlarged anterior or posterior teeth and without a gap or small intermediate teeth between anterior and lateral teeth in the upper jaw. Two spineless dorsal fins present, the first with its origin over the interspace between the pectoral and pelvic bases; pectoral fins moderately large, not expanded and raylike, without triangular anterior lobes that cover the gill slits; pelvic fins small, with vent continuous with their inner margins; anal fin absent; caudal fin with a moderately long dorsal lobe but with ventral lobe absent; vertebral axis elevated into the dorsal caudal lobe. Intestinal valve of spiral type.

4.1 FAMILY PRISTIOPHORIDAE Bleeker, 1859 PRISTIOP

Family Pristiophoroidei Bleeker, 1859, Act.Soc.Sci.Ind.Neerl., 4(3):xii.

Synonymy : Family Pliotremidae Jordan, 1923.

FAO Names: En - Saw sharks; Fr - Requins scie; Sp - Tiburones sierra.

Field Marks : Long, flat snout with lateral sawteeth and ventral barbels, two spineless dorsal fins and no anal fin.

Habitat, Distribution and Biology : Sawsharks are little-known temperate and tropical benthic and epibenthic inhabitants of the continental and insular shelves and upper slopes from close inshore to at least 915 m depth. Temperate sawsharks are found in shallow bays and estuaries down to offshore sand and gravel banks at modest depths, but one tropical species is a deepwater slope inhabitant at 640 m and below. The sawshark family is presently confined to the western North Atlantic in the vicinity of the Bahamas, the southeastern Atlantic and western Indian Ocean from the western Cape, South Africa, to southern Mozambique, apparently the Arabian Sea (where an undescribed species may occur), and the western Pacific off Japan, the Koreas, China, the Philippines and Australia. Fossil finds indicate that sawsharks were formerly more widespread, in the eastern Pacific and eastern North Atlantic.

Sawsharks are small and very slender, with a maximum total length of about 137 cm.

Several sawsharks are abundant where they occur, and are found in large schools or feeding aggregations. Despite their abundance, their habits are poorly known. At least one species shows segregation by depth within populations, with adults in deeper water than young.

Sawsharks are ovoviviparous, and may have litters of 7 to 17 large young that are 28 to 35 cm long at birth. Apparently sawshark fetuses gain nutrients primarily from their large yolk sacks, which are resorbed just before birth. Apparently the large lateral rostral teeth erupt before birth in sawsharks, but to prevent injury to the mother these large teeth lie flat against the rostrum in fetuses until after birth. Smaller teeth erupt between the large ones after birth. - 131 -

Food habits of sawsharks are poorly known, but their prey includes small fishes, crustaceans and squids. The long rostral barbels may have taste sensors, that these sharks trail along the bottom like those of sturgeons (Acipenseridae) and catfishes (Siluriformes) to locate prey. The long, rather delicate rostrum has lateral line and ampullal sensors for vibration and electrolocation, like a paddlefish (Polyodontidae) snout. The lateral rostral teeth, flat snout and head, enlarged occipital condyles, and specialized cervical vertebrae of sawsharks are evident modifications that allow these sharks to use their rostra as offensive weapons to kill their prey and possibly stir up bottom sediments to rouse prey organisms, but unlike the batoid sawfishes (Pristidae) this behaviour has not been observed, probably because sawsharks apparently have not been kept in captivity with any success (unlike sawfishes) and have not been studied underwater where they occur. The very short jaws and long oral and gill cavities of sawsharks suggest that they are capable of suddenly sucking prey into their mouths.

Because of their small size and small, cuspidate teeth sawsharks are considered to be inoffensive to people (unlike large sawfishes which have occasionally injured and even killed bathers and may be a hazard to fishermen when caught in nets and on line gear). The rostra] teeth of sawsharks are sharp as needles though apparently nontoxic, so that these fishes should be handled with care to prevent puncture wounds on one's limbs.

Interest to Fisheries : Considerable fisheries for sawsharks have occurred off southern Australia. They are taken and used in the western North Pacific to some extent, but details are sketchy. Sawsharks are commonly taken in the southwestern Indian Ocean off South Africa and southern Mozambique, but may be little utilized there. Sawsharks are caught in bottom trawls, and used fresh for human consumption.

Remarks : Arrangement of this family follows Springer & Bullis (1959). 6 pairs of gill slits Key to Genera and Species 1a. Six pairs of gill openings (Fig. la). Larger rostral teeth serrated (Fig. 2) ...... Pliotrema warreni

1b. Five pairs of gill openings (Fig. 1b). Larger rostral teeth smooth (Pristiophorus) a. Pliotrema 5 pairs of gill slits 2a. Lateral trunk denticles largely tri- cuspidate. Preoral snout longer, about 31 to 32% of total length (Fig. 3) ...... Pristioph orus schroederi

2b. Lateral trunk denticles largely uni- b. Pristiophorus Fig. 1 cuspidate. Preoral snout less than 30% of total length

3a. Rostrum relatively short and broad, distance from rostral tip to barbels much greater than distance from barbels to mouth. Dorsal and pectoral

fins partially naked in large specimens (Fig. 4) .... Pristiophorus nudipinnis Pliotrema warreni Fig. 2

dorsal view Pristiophorus schroederi Fig.3

dorsal view

Pristiophorus nudipinnis Fig. 4 - 132 -

3b. Rostrum long and narrower, distance from rostral tip to barbels about equal or slightly greater than distance from bar- bels to mouth. Dorsal and pectoral fins covered with denticles in large speci- a. dorsal view mens (Figs 5a,b) ...... Pristiophorus cirratus

Pristiophorus japonicus Pristiophorus cirratus

lateral view b. Pristiophorus japonicus Fig. 5

Pliotrema Regan, 1906 PRISTIOP Plio

Genus : Pliotrema Regan, 1906a, Ann.Natal Mus., 1(1):1.

Type Species : Pliotrema warreni Regan, 1906, by monotypy.

Synonymy : None.

Diagnostic Features : Six pairs of gill slits. Large rostral sawteeth with posterior serrations. Teeth with prominent transverse ridges on basal ledges.

Pliotrema warreni Regan, 1906 PRISTIOP PIio 1

Pliotrema warreni Regan, 1906a, Ann.Natal Mus., 1(1):1, pl. 1. Syntypes: British Museum (Natural History), BMNH 1905.6.8.9 is one of two specimens, each 750 mm total length. Type Locality: Two localities in South Africa given, Natal, 73 m depth, and False Bay, Cape of Good Hope.

Synonymy : None.

FAO Names : En - Sixgill sawshark; Fr - Requin scie flutian; Sp - Tiburón sierra del Cabo.

teeth of saw barbel

underside of head

Field Marks : Six pairs of gill slits, sawlike snout with barbels.

Diagnostic Features : See genus. upper and lower tooth - 133 -

Geographical Distribution : Temperate and subtropical waters of the western Indian Ocean: Distribution centred on the south- eastern Cape coast of South Africa, but ranging from False Bay to central Natal and southern Mozambique.

Habitat and Biology : A common benthic and epibenthic shark of the continental shelf and upper slope at depths of 60 to at least 430 m. It is most abundant in southeastern Cape waters at 60 to 120 m, but occurs in deeper water off Natal (110 m and below), where adults are partially segregated from young by occurring in greater depths. Ovoviviparous, with 5 to 7 young in a litter in two females but with others having 7 to 17 developing eggs. Eats small fish (including Champsodon), crustaceans and squids. Size : Maximum total length at least 136 cm; males maturing at about 83 cm and reaching at least 112 cm; females maturing at about 110 cm and reaching at least 136 cm; size at birth about 35 cm. Interest to Fisheries : Commonly taken by bottom trawlers off South Africa and southern Mozambique, but usage not known.

Literature : Fowler (1941); Smith (1949); Bass, d'Aubrey & Kistnasamy (1975c).

Pristiophorus Müller & Henle, 1837 PRISTIOP Prist

Genus : Pristiophorus Müller & Henle, 1837, Ber.K.Preuss.Akad.Wiss.Berl., 2:116.

Type Species : Pristis cirratus Latham, 1794, by monotypy.

Synonymy : None.

Field Marks : Rostrat saw and barbels, five pairs of gill slits, two spineless dorsal fins and no anal fin.

Diagnostic Features : Five pairs of gill slits. Large rostral sawteeth without posterior serrations. Teeth without prominent transverse ridges on basal ledges.

Remarks : The present systematic arrangement of Pristiophorus follows Springer & Bullis (1960) with modifications. Or Bruce Welton (pers.comm.) notes that he examined specimens of a Pristiophorus collected in deep water in the Arabian Sea while in Karachi. The identification of these specimens is uncertain, and could represent a new species of sawshark.

Pristiophorus cirratus (Latham, 1794) PRISTIOP Prist 2

Pristis cirratus Latham, 1794, Trans.Linn.Soc.London, 2(25):281, pl. 26, fig. 5, pl. 27. Holotype possibly in British Museum Natural History)?, male about 1020 mm long, from Port Jackson, Australia.

Synonymy : Squalus anisodon Lacepède, 1802; Squalus tentaculatus Shaw, 1804. FAO Names : En - Longnose sawshark; Fr - Requin scie à long nez; Sp - Tiburón sierra trompudo. - 134 -

dorsal view

Field Marks : Five pairs. of lateral gill slits, long, narrow sawshark snout 27 to 28% of total length, largely lanceolate denticles, two spineless dorsal fins, and no anal fin.

Diagnostic Features : Rostrum long, narrow, and narrowly tapering, length of preoral snout 27 to 29% of total length. Bases of rostral barbels about 1.2 to 1.3 times closer to rostral tip than mouth; distance from rostral barbels to nostrils slightly less or equal to distance from nostrils to first to fourth gill slits. About 9 or 10 large rostral teeth on each side of rostrum in front of rostral barbels, 9 behind them. Distance from mouth to nostrils 1.3 to 1.4 times internarial space. Tooth rows 39 to 49 in upper jaw. Dorsal and pectoral fins covered with denticles in large specimens. Lateral trunk denticles largely unicuspidate. First dorsal origin behind free rear tips of pectorals by eye length or slightly less.

Geographical Distribution : Western Pacific: Australia (South and

Western Australia, New South Wales, Tasmania, Victoria), possibly the Philippines.

Habitat and Biology : A common temperate-subtropical sawshark of the continental shelf and upper slope of Australia, found near or on the bottom from close inshore to at least 311 m depth. Occurs in bays and estuaries, but more abundant offshore at about 37 to 146 m on sandy or gravel-sand bottoms. Apparently occurs in schools or aggregates, possibly for feeding. Ovoviviparous, said to "breed in the winter month" (Whitley, 1940). Eats small fishes, including coronet fishes (Fistularia), and crustaceans.

Size : Maximum total length about 137 cm, size at birth about 31 to 34 cm.

Interest to Fisheries : This abundant small shark has formed the basis for a considerable bottom trawl fishery off southern Australia, the catches from which are utilized fresh for human consumption. Apparently the meat of this shark is excellent eating.

Local Names: AUSTRALIA: Common sawshark, Little sawshark.

Literature : Günther (1870); Garman (1913); Whitley (1940); Fowler (1941); Springer & Bullis (1960); Stead (1963).

Remarks : See the account of P. japonicus for notes on the difficulties in separating that species from P. cirratus. I have examined two specimens of sawsharks from the Philippines which may be this species or P. japonicus but may differ from P. cirratus in having the rostral barbels slightly closer to the mouth than the snout tip possibly variable in P. cirratus. Whether the Philippine specimens can be assigned to either species hinges on whether or not these species can be separated.

Pristiophorus japonicus Günther, 1870 PRISTIOP Prist 3

Pristiophorus japonicus Günther, 1870, Cat.Fish.British Mus., 8:433. Syntype : British Museum (Natural History , BMNH 1862.11.1.37. Type Locality : Japan.

Synonymy : None. - 135 -

FAO Names: En - Japanese sawshark; Fr - Requin-scie moustache; Sp - Tiburón sierra japonés.

Field Marks : Five pairs of lateral gill slits, long, narrow sawshark snout 26 to 29% of total length, largely lanceolate denticles, two spineless dorsal fins, and no anal fin.

Diagnostic Features: Rostrum long, narrow, and narrowly tapering, length of preoral snout 26 to 29% of total length. Bases of rostral barbels about 1.1 to 1.2 times closer to mouth than rostral tip; distance from rostral barbels to nostrils about equal to distance from nostrils to first to fourth gill slits. About 15 to 26 large rostral teeth on each side of rostrum in front of rostral barbels, 9 to 17+ behind them. Distance from mouth to nostrils 1.1 to 1.2 times internarial space. Tooth rows 34 to 58 in upper jaw. Dorsal and pectoral fins covered with denticles in large specimens. Lateral trunk denticles largely unicuspidate. First dorsal origin behind free rear tips of pectorals by eye length or more.

Geographical Distribution : Western North Pacific: Japan, the Koreas, northern China, Taiwan, Island, possibly the Philippines.

Habitat and Biology : A common sawshark of the western North Pacific continental shelves and upper slopes on or near bottom. Lives in coastal waters, on sand or mud bottoms. Ovoviviparous, number of young usually 12. Feeds an small bottom organisms; said to use barbels along bottom and poke the bottom with its snout.

Size : Maximum total length for adult females about 136 cm.

Interest to Fisheries : Probably of limited importance, though in Japan its meat is considered of high quality and used to prepare "kameboko" for human consumption. Literature : Günther (1870); Garman (1913); Fowler (1941), Springer & Bullis (1960); Masuda, Araga & Yoshino (1975).

Remarks : This species is very close to P. cirratus and was referred to that species by earlier writers. Günther (1870) distinguished the two species by differences in tooth counts, and by comparison of the distance between rostral barbels and nostrils (equal to distance between nostrils and fourth gill slits in cirratus, nearly equal to that between nostrils and first gill slits in japonicus). However, the proportional character fails in that some japonicus examined have the barbel-nostril interspace equal to that from the nostrils to fourth gill slits, and tooth counts overlap in the material examined and in literature counts. Use of tooth counts is also confounded by increases in tooth counts with growth in this and probably other sawsharks (a small Japanese sawshark 49.5 cm total length had 34 rows of upper teeth, a large one about 136 cm 57 rows, while intermediate-sized specimens had intermediate counts). Because of the limited material examined of P. cirratus, I am uncertain if rostral tooth counts and the position of the barbels on the snout (closer to the snout tip than mouth in cirratus, slightly closer to the mouth than the snout tip in japonicus) are valid differences between these species. The separation of the two species P. cirratus and P. japonicus is unsatisfactory at present, but I hesitate to merge them until more adequate samples than I have been able to examined' can be compared.

Sawsharks from the Philippines may be this species or P. cirratus (see that species for a discussion).

Pristiophorus nudipinnis Günther, 1870 PRISTIOP Prist 4

Pristiophorus nudipinnis Günther, 1870, Cat.Fishes British Mus., 8:432. Syntype : In British Museum (Natural History), BMNH 1869.2.24.2, 1040 mm male, probably adult. Type Locality : Tasmania or South Australia.

Synonymy : ? Pristiophorus owenii Günther, 1870.

FAO Names : En - Shortnose sawshark; Fr - Requin scie à nez court; Sp - Tiburón sierra ñato. - 136 -

dorsal view

Field Marks : Five pairs of lateral gill slits; rather broad, short sawshark snout 23 or 24% of total length, rostral barbels considerably closer to mouth than rostrum tip, largely lanceolate denticles, two spineless dorsal fins, and no anal fin.

Diagnostic Features: Rostrum rather short, broad, and abruptly tapering, length of preoral snout 23 or 24% of total length. Bases of rostral barbels about 1.4 to 1.5 times closer to mouth than rostral tip; distance from rostral barbels to nostrils about equal to distance from nostrils to rear corners of mouth. About 13 large rostra] teeth on each side of rostrum in front of rostral barbels, 6 behind them. Distance from mouth to nostrils 0.9 times internarial space. Tooth rows 33 to 35 in upper jaw. Dorsal and pectoral fins largely naked in large specimens. Lateral trunk denticles largely unicuspidate. First dorsal origin about opposite free rear tips of pectorals.

Geographical Distribution: Western South Pacific: Australia (South and Western Australia, Victoria, Tasmania, New South Wales).

Habitat and Biology : A common temperate-subtropical saw- shark of the Australian continental shelf, found on or near the bottom at 37 to 165 m depth. Ovoviviparous.

Size : Maximum total length at least 122 cm; size at birth about 28 cm.

Interest to Fisheries : Caught with bottom trawls off southern Australia, and used fresh for human consumption.

Local Names : AUSTRALIA: Southern sawshark.

Literature : Günther (1870); Garman (1913); Whitley (1940); Fowler (1941); Springer & Bullis (1960); Stead (1963).

Remarks : Pristiophorus owenii was described by Günther (1870) from a 32.3 cm newborn specimen without locality (BMNH 1859.9.11.1 in the British Museum (Natural History). This was distinguished from other sawsharks by its equally long rostral teeth (other species have teeth of different sizes). Garman (1913) noted that this species differed from P. cirratus only in its regular-sized teeth, but thought this might be a juvenile characteristic. Fowler (1941 synonymized P. owenii with P. cirratus, but Spriger & Bullis (1960) resurrected the species. They noted that P. owenii was similar to P. nudipinnis in having a short snout, but distinguished owenii by its rostral teeth. They noted that a juvenile specimen of nudipinnis illustrated by McCulloch (1911) had rostral teeth of varied sizes. However, McCulloch's sawshark and another iuvenile nudipinnis of similar size and rostral teeth examined by me in the Australian Museum (Sydney, AMS I 21303-001) are considerably larger (44.5 to 44.6 cm long) than a newborn specimen of apparent nudipinnis (SU 25492, 27.5 cm total length) from Australia which has owenii-like even rostral teeth. Another Australian newborn sawshark (SU 20805, 33.4 cm total length) is apparently P. cirratus,yet has owenii-like sawteeth. All this and Whitley's (1940, fig. 173, no. 1) illustration of a 30 cm late fetal cirratus with even teeth leads me to believe that such teeth are characteristic of late fetal and newborn sawsharks as suspected by Garman, 1913). I include P. owenii in synonymy of P. nudipinnis because of its short snout, but consider this tentative because of the absence of locality data for the holotype of owenii.

Pristiophorus schroederi Springer & Bullis, 1960 PRISTIOP Prist 1

Pristiophorus schroederi Springer & Bullis, 1960, Bull.Mar.Sci.Gulf Caribb., 10(2):241, figs 1-3, 5. Holotype: US National Museum of Natural History, USNM 185946, 383 mm immature female. Type Locality: About 15 miles east of Dog Rocks, Cay Sol Bank, 24°05'N, 79°46'W, at 640 m depth.

Synonymy : None. - 137 -

FAO Names : En - Bahamas sawshark; Fr - Requin scie d'Amérique; Sp - Tiburón sierra americano.

dorsal view

teeth of saw barbel

underside of head

Field Marks: Five pairs of lateral gill slits, extremely long, narrow sawshark snout 31 to 32% of total length, largely tricuspidate lateral denticles, two spineless dorsal fins, and no anal fin. Diagnostic Features : Rostrum very long, narrow, and narrowly tapering, length of preoral snout 31 to 32% of total length. Bases of rostral barbels about 1.1 times closer to mouth than rostral tip; distance from rostral barbels to nostrils about equal to distance from nostrils to second to fourth gill slits. About 13 to 14 large rostral teeth on each side of rostrum in front of rostral barbels, 9 to 10 behind them. Distance from mouth to nostrils 1.2 times internarial space. Tooth rows 33 to 36 in upper jaw. Dorsal and pectoral fins covered with denticles in large specimens. Lateral trunk denticles largely tricuspidate. First dorsal origin about opposite free rear tips of pectorals.

Geographical Distribution : Western North Atlantic: Bahamas region, between Cuba, Florida and the Bahamas.

Habitat and Biology : A little-known, deep-water, tropical sawshark of the continental and insular slopes of the Bahamas region, occurring on or near the bottom at depths from 640 to 915 m.

Size : Maximum total length at least 80 cm.

Interest to Fisheries: None at present.

Literature : Springer & Bullis (1960).

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