Family Scylliorhinoidae), Ann.Lyceum Nat.Hist.N.Y., 7(32):408

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7.4 FAMILY HEMISCYLLIIDAE Gill, 1862 HEMIS

Subfamily Hemiscylliinae Gill, 1862 (Family Scylliorhinoidae), Ann.Lyceum Nat.Hist.N.Y., 7(32):408.

Synonymy : Subfamily Chiloscylliinae Gill, 1862 (Family Scylliorhinoidae).

FAO Names : En - Bamboo sharks, Longtailed carpetsharks; Fr - Requins chabot; Sp - Bamboas.

Field Marks : Small, slender sharks with nasoral grooves, perinasal grooves, short barbels, small transverse mouths in front of eyes, dorsolateral eyes, large spiracles below eyes, no lateral skin flaps on head, two spineless dorsal fins, the second dorsal origin well ahead of the anal origin, a long, low keel-like rounded anal fin separated from the lower caudal origin by a narrow notch, and a long precaudal tail much greater. than the head and body length.

Diagnostic Features : Body cylindrical or slightly depressed, with or without ridges on sides. Head narrow to moderately broad and cylindrical to somewhat flattened, without lateral flaps of skin, snout broadly rounded or slightly pointed; eyes dorsolaterally situated on head, without subocular pockets; spiracles very large, subequal in size to eyes and somewhat below them; gill slits small, fifth overlapping fourth; internal gill slits without filter screens; nostrils with short, pointed barbels and distinct circumnarial folds and grooves around outer edges of incurrent apertures; mouth small, subterminal on head, and nearly transverse, without a symphyseal groove on chin; teeth not strongly differentiated in jaws, with a medial cusp, lateral cusplets present or not, and weak labial root lobes; tooth rows 26 to 35/21 to 32. Caudal peduncle without lateral keels or precaudal pits. Dorsal fins equal-sized, first dorsal with origin varying from over the pelvic bases to well behind them and insertion well behind the pelvic rear tips; pectoral fins small, broad and rounded, as large as pelvic fins or slightly larger, with fin radials not expanded into fin web; pelvic fins about as large as dorsals but slightly larger than anal fin; anal fin somewhat smaller than second dorsal, with its origin behind second dorsal insertion; anal fin with broad base and broadly rounded, keel-like apex, separated by a narrow notch much less than base length from lower caudal origin; caudal fin with its upper lobe hardly elevated above the body axis, less than a fifth as long as the entire shark, with a strong terminal lobe and subterminal notch but no ventral lobe. Supraorbital crests present on cranium, not laterally expanded. Valvuler intestine of ring type. Colour pattern of dark saddles and dark or light spots present, or colour plain.

Habitat, Distribution and Biology: These are common, small, harmless, inshore bottom sharks of continental waters of the tropical western Pacific, ranging from Madagascar in the west to Japan, the Philippines, and the Australian region in the east. One genus (Hemiscyllium) is confined to Australia and New Guinea, but the second (Chiloscyllium) is wide-ranging. They commonly occur in the intertidal, in tidepools on rocky or coral reefs close inshore, sometimes in water sufficient only to cover them. Their slender bodies and strong, muscular, leg-like paired fins are ideal for clambering on reefs and in crevices. These sharks are small, less than 1 m maximum length. At least some of the species are oviparous, depositing eggs on the bottom in oval egg cases. Food of these sharks is little known, but probably includes small bottom fishes and invertebrates. Several of the species are very hardy and can live over a decade in captivity and even reproduce there.

Interest to Fisheries : Hemiscyllium species are little utilized for fisheries, but Chiloscyllium species are commonly caught in smallscale artisanal fisheries and by bottom trawlers in the western Pacific and eastern central Indian Ocean.

Remarks : The arrangement of this family follows Garman (1913), Fowler (1941) and Whitley (1967).

Key to Genera

1a. Nostrils subterminal on snout (Fig. la). Eyes and supraorbital ridges hardly elevated. Preoral snout long, mouth closer to eyes than snout tip. No black hood on head or large dark spot or spots on sides of body above pectoral fins (Fig. 1b) ……...... Chiloscyllium

nostrils subterminal on snout

b. lateral view

a. underside of head Chiloscyllium Fig.1 - 189 -

Nostrils terminal on snout (Fig. 2a). Eyes and supraorbital ridges prominently elevated. Preoral snout short, mouth closer to snout tip than eyes. A large dark spot or spots on sides of body above pectoral fins, or a black hood on head (Fig. 2b) ...... …………………………...... Hemiscyllium nostrils virtually terminal on snout

b. lateral view

a. underside of head Hemiscyllium Fig.2

Chiloscyllium Müller & Henle, 1837 HEMIS Chilo

Genus: Chiloscyllium Müller & Henle, 1837, Ber.K.Preuss.Akad.Wiss.Berl., 2:112 (no species mentioned).

Type Species : Scyllium plagiosum Bennett, 1830, by subsequent monotypy of Müller & Henle, in Smith, 1837, Proc.Zool.Soc. Lond., 5:85; also by subsequent designation of Gill, 1862, Ann.Lyceum Nat.Hist.N.Y., 7:408.

Synonymy : Synchismus Gill,1862.

Diagnostic Features : Snout relatively long, nostrils subterminal and well separated from snout tip. Eyes and supraorbital ridges hardly elevated. Mouth slightly closer to eyes than snout tip. Lower labial folds usually connected across chin by a dermal fold. Pectoral and pelvic fins relatively thin, not heavily muscular. No black hood on head or large dark spot or spots on sides of body above pectoral fins.

Remarks : The arrangement of this genus follows Garman (1913) and Fowler (1941). The genus is long overdue for a detailed systematic review from a large number of specimens from different localities, and the arrangement of the genus presented here is very tentative. The six species recognized here are probably valid, but there may be additional species that are being confused with the valid ones (especially with C. griseum and C. punctatum).

Key to Species :

1a. Body and tail very slender. Anal fin origin far behind free rear tip of second dorsal, length of anal fin from origin to free rear tip subequal to length of hypural caudal lobe from lower caudal origin to subterminal notch. Colour pattern with numerous small dark spots and bars ...... ………………………………...... C. indicum

1b. Body and.tail moderately slender to relatively stout. Anal fin origin below or close behind free rear tip of second dorsal, length of anal fin considerably shorter than hypural caudal lobe. Colour pattern varied but without numerous small dark spots and bars

2a. Ground colour of body dark with numerous light spots

3a. Dorsal fins large and angular, snout tip truncated. Colour pattern without transverse dark bands, spots blue ...... …...... C. caerulopunctatum

3b. Dorsal fins smaller and more rounded, snout tip broadly rounded. Colour pattern with transverse broad dark saddles, spots white ...... ……...... C. plagiosum

2b. Ground colour of body light, with or without scattered dark spots or dusky bands

4a. Dorsal fins smaller than pelvic fins, dorsals without projecting free rear tips ...... …………………………...... C. griseum

4b. Dorsal fins larger than pelvic fins, dorsals with projecting free rear tips

5a. A lateral ridge present on each side of trunk. First dorsal origin over or behind pelvic fin bases. No colour pattern ...... ………...... C. arabicum

5b. No lateral ridges on trunk. First dorsal origin over anterior halves of pelvic fin bases. A colour pattern of saddles and a few scattered dark spots in young ...... ………...... …...... C. punctatum - 190 -

Chiloscyllium arabicum Gubanov, 1980 HEMIS Chilo 3

Chiloscyllium arabicum Gubanov, in Gubanov & Schleib (eds), 1980, Sharks of the Arabian Gulf, 14, figs 6-7, pl. Holotype: Uncertain. Type Locality: Persian Gulf.

Synonymy : None.

FAO Names : En - Arabian carpetshark; Fr - Requin-chabot camot; Sp - Bamboa arabiga.

Field Marks : Mouth well in front of eyes, spineless dorsal fins far posterior on tail, greatly elongated thick precaudal tail, long and low anal fin just anterior to caudal fin, lateral ridges on trunk, dorsal fins with elongated free rear tips, first dorsal origin opposite or just behind pelvic insertions, no colour pattern.

Diagnostic Features: Body and tail moderately slender. Snout fairly thick and rounded anteriorly; a lateral ridge present on each side of trunk. Dorsal fins large and angular, somewhat larger than pelvic fins, dorsals with projecting free rear tips; interdorsal space very long, over twice first dorsal base; first dorsal origin over or behind pelvic fin bases; origin of anal fin somewhat behind free rear tip of first dorsal, anal fin length from origin to free rear tip somewhat less than hypural caudal lobe from lower caudal origin to free rear tip. No colour pattern, colour light brown.

Geographical Distribution : As presently known confined to the "Gulf" between Iran and the Arabian Peninsula.

Habitat and Biology : A common inshore to offshore bottom shark in the "Gulf", especially during the summer, depths from 3 to 100 m.

Size : Maximum total length 70 cm.

Interest to Fisheries : Minimal at present, apparently little utilized in the "Gulf" (Gubanov & Schleib, 1980).

Literature : Gubanov & Schleib (1980).

Remarks : This inadequately described species is apparently very close to C. punctatum, but is provisionally recognized here.

Chiloscyllium caerulopunctatum Pellegrin, 1914 HEMIS Chila 4

Chiloscyllium caerulopunctatum Pellegrin, 1914, Bull. Soc.ZooI.France, 39:230. Holotype: Muséum National d'Histoire Naturelle, Paris, 670 mm female. Type Locality: Fort Dauphin, Madagascar.

Synonymy : None.

FAO Names : En - Bluespotted bambooshark; Fr - Requin-chabot à taches bleues; Sp - Bamboa estrellada. - 191 -

Field Marks : Mouth well in front of eyes, spineless dorsal fins far posterior on tail, greatly elongated thick precaudal tail, long and low anal fin just anterior to caudal fin, lateral ridges on trunk, dorsal fins very large, colour dark with light blue spots but no dark saddles.

Diagnostic Features : Body and tail stout, snout thick and truncated anteriorly; a lateral ridge present on each side of trunk. Dorsal fins very large and angular, considerably larger than pelvic fins, dorsals without projecting free rear tips; interdorsal space very short, less than first dorsal base; first dorsal origin over pelvic fin bases; origin of anal fin slightly behind free rear tip of first dorsal, anal fin length from underside of head dermal denticles origin to free rear tip considerably less than hypural caudal lobe from lower caudal origin to free rear tip. Colour pattern of light blue spots on a dark grey-brown background, but no dark transverse bands.

Geographical Distribution : Western Indian Ocean: Mada- gascar. Until recently only known from the holotype. Dr Marie- Louise Bauchot and Ms Gabriella Bianchi (pers.comm.) recently saw this species in market catches in Madagascar, confirming the occur- rence of the species there.

Habitat and Biology : A rare and little-known carpetshark, apparently confined to Madagascar. Virtually nothing is known of its biology.

Size : Maximum total length at least 67 cm.

Interest to Fisheries : None at present.

Literature : Bass, d'Aubrey & Kistnasamy (1975b); M.-L. Bauchot & G. Bianchi (pers. Comm.).

Remarks: Fowler (1941) synonymized this species with the similar C. plagiosum, but Bass, d'Aubrey & Kistnasamy (1975b) retained it as a valid species without comparing it with C. plagiosum or other Chiloscyllium species. After comparing the redescription of the holotype of C. caerulopunctatum in Bass, d'Aubrey & Kistnasamy (1975b) with specimens of C. plagiosum I tentatively recognize this species as being valid. It apparently differs from C. plagiosum in having larger dorsal fins, a shorter, blunter snout, possibly wider mouth, and a different coloration, with smaller blue rather than white spots and lighter ground colour.

Chiloscyllium griseum Müller & Henle, 1838 HEMIS Chilo 1

Chiloscyllium griseum Müller & Henle, 1838, Syst.Beschr.Plagiost., pt. 1:19, pl. 4. Holotype: Muséum National d'Histoire Naturelle, Paris. Type Locality: "Indian. Japan."

Synonymy : Scyllium griseum van Hasselt, 1824 (? nomen nudum); ? Chiloscyllium obscurum Gray, 1851 (nomen nudum); Chiloscyllium hasseltii Bleeker, 1852. - 192 -

FAO Names : En - Grey bambooshark; Fr - Requin-chabot gris; Sp - Bamboa gris.

adult

juvenile

Field Marks : Mouth well in front of eyes, spineless dorsal fins far posterior on tail, greatly elongated thick precaudal tail, long and low anal fin just anterior to caudal fin, no lateral ridges on trunk, dorsal fins without elongated, free rear tips, first dorsal origin about opposite pelvic insertions, often no colour pattern in adults, but transverse bands in young.

Diagnostic Features: Body and tail fairly stout; snout rounded anteriorly; no lateral ridges on trunk. Dorsal fins fairly large and rounded, somewhat smaller than pelvic fins, dorsals without projecting free rear tips; interdorsal space short, slightly greater than first dorsal base; first dorsal origin about over pelvic fin insertions; origin of anal fin slightly behind free rear tip of first dorsal, anal fin length from origin to free rear tip somewhat less than hypural caudal lobe from lower caudal origin to free rear tip. Colour: adults usually light brown, without a colour pattern, but young with prominent dark transverse bands.

Geographical Distribution : Indo-West Pacific: The "Gulf "between Iran and the Arabian Peninsula, Pakistan, India, Malaysia, Thailand, Indonesia, China, Japan, the Philippines, Papua New Guinea.

Habitat and Biology : A common inshore bottom shark. Oviparous, deposits eggs in small, oval egg cases on the bottom. Probably feeds mainly on invertebrates.

Size : Maximum total length at least 74 cm.

Interest to Fisheries : Regularly taken in inshore fisheries off Pakistan, India and Thailand, and utilized for human food. Literature : Garman (1913); Fowler (1941); Gubanov & Schleib (1980).

Remarks : This species was described as new by Müller & Henle without mention of the earlier Scyllium griseum van Hasselt, 1824. Fowler (1941) considered van Hasselt's species as without description, but I have not seen its original account and so list it as a tentative nomen nudum at present. Quite likely Müller & Henle based their C.griseum on the earlier Scyllium griseum, as they were apparently aware of van Hasselt's work in Java.

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Chiloscyllium indicum (Gmelin, 1789) HEMIS Chilo 2

Squalus indicus Gmelin, 1789, Caroli Linnaei Syst.Nat., 1(3):1503. Holotype: None ? Type Locality: "Oceano Indico".

Synonymy : ?(Squalus) colax Meuschen, 1781 (nonbinomial?); Squalus tuberculatus Bloch & Schneider, 1801; Squalus gronovianus Shaw, 1804; ? Squalus (Scyliorhinus) dentatus Blainvilie, 1816 name only); Chiloscyllium phymatodes Bleeker, 1852; Squalus caudatus Gronow, in Gray, 1854.

Other Scientific Names Recently in Use : Chiloscyllium colax (Meuschen, 1781).

FAO Names : En - Slender bambooshark; Fr - Requin-chabot élégant; Sp - Bamboa elegante.

Field Marks : Mouth well in front of eyes, spineless dorsal fins far posterior on tail, greatly elongated slender precaudal tail, long and low anal fin just anterior to caudal fin, lateral ridges on trunk, dorsal fins without elongated free rear tips, first dorsal origin opposite or just behind pelvic insertions, colour pattern of numerous small dark spots and dashes.

Diagnostic Features: Body and tail very slender; snout narrowly rounded anteriorly; a lateral ridge present on each side of trunk. Dorsal fins small and rounded, smaller than pelvic fins, and without projecting free rear tips; interdorsal space fairly long, nearly twice first dorsal base; first dorsal origin over or behind pelvic fin bases; origin of anal fin far behind free rear tip of first dorsal, anal fin length from origin to free rear tip about equal hypural caudal lobe from lower caudal origin to free rear tip. A colour pattern of numerous dark brown or blackish spots and dashes underside of head on light brown background.

Geographical Distribution : Indo-West Pacific: Arabian Sea to India, Sri Lanka, Singapore, Thailand, Indonesia, Viet Nam, Taiwan Island, ? Republic of Korea, ? Japan, the Philippines, Solomon Islands.

Habitat and Biology : A common but little-known inshore bottom shark. Ovi- parous.

Size : Maximum total length about 65 cm.

Interest to Fisheries: Regularly taken in inshore fisheries in India, Sri Lanka and Thailand, and utilized for human food.

Literature : Garman (1913); Fowler (1941); Gubanov & Schleib (1980).

Remarks : Whitley (1939) proposed that Squalus colax Meuschen, 1781 was the earliest name for this species, but reference to that work (Meuschen, 1781 indicates that although colax apparently refers to the Gronow species later named Squalus indicus, it was never proposed in a binomial form but simply listed as colax. Apparently colax is nonbinomial, and is not available for this species. - 194 -

Chiloscyllium plagiosum (Bennett, 1830) HEMIS Chilo 5

Scyllium plagiosum Bennett, 1830, Mem.life serv.Sir Stamford Raffles, Fishes, 694. Holotype: None?. Type Locality: Sumatra.

Synonymy : Scyllium ornatum Gray, 1832; Chiloscyllium plagiosum var. interruptum Bleeker, 1852.

FAO Names: En - Whitespotted bambooshark; Fr - Requin-chabot à taches blanches; Sp - Bamboa punteada.

Field Marks : Mouth well in front of eyes, spineless dorsal fins far posterior on tail, greatly elongated thick precaudal tail, long and low anal fin just anterior to caudal fin, lateral ridges on trunk, dorsal fins without elongated free rear tips, first dorsal origin opposite or just behind pelvic insertions, colour pattern of numerous white spots and transverse bands on a dark background.

Diagnostic Features : Body and tail fairly stout; snout rounded anteriorly; a lateral ridge present on each side of trunk. Dorsal fins moderately large and rounded or angular, about equal in size to pelvic fins, dorsals without projecting free rear tips; interdorsal space short, slightly over length of first dorsal base; first dorsal origin over or behind pelvic fin bases; origin of anal fin somewhat behind free rear tip somewhat less than hypural caudal lobe from lower caudal origin to free rear tip. Colour: a prominent colour pattern of numerous white spots on a dark brown background, with darker brown or blackish transverse bands.

Geographical Distribution : Indo-West Pacific: India, Sri Lanka, ? Malaysia, Singapore, Thailand, Indonesia, Viet Nam, China, including Taiwan Island, Japan, the Philippines.

Habitat and Biology : A common but little-known inshore bottom shark. Oviparous. Size : Maximum total length 95 cm, adult males 67 to 69 cm, an adult female 95 cm.

Interest to Fisheries : Regularly taken in inshore fisheries in India, Thailand, China, and utilized for human consumption.

Literature : Garman (1913); Fowler (1941); Chen (1963); Gubanov & Schleib (19B0).

Chiloscyllium punctatum Müller & Henle, 1838 HEMIS Chilo 6

Chiloscyllium punctatum Müller & Henle, 1838, Syst.Beschr.Plagiost., pt. 1:19, pl. 4. Holotype: Rijksmuseum van Natuurlijke Historie, Leiden. Type Locality: Java. Synonymy : ? Squalus (Scyliorhinus) russellianus Blainville, 1816 (nomen nudum); Scyllium punctatum van Hasselt, 1823; Chiloscyllium margaritiferum Bleeker, 1964.

FAO Names : En - Brownbanded bambooshark; Fr - Requin-chabot bambou; Sp - Bamboa estriada.

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