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Tuatara: Volume 5, Issue 1, January 1953
A Guide to the Lesser Chordates and the Cartilaginous Fishes
A Guide to the Lesser Chordates and the Cartilaginous Fishes
The Animals considered here are all, with the exception of the lamprey, marine aquatic chordates, and although much varied in size, ranging from Cephalodiscus where the individuals are only 1/25th of an inch to the basking shark of 40 feet, and as varied in form, these chordates differ from all others in the absence of bone. Some are only of academic interest but many of the others, the rays and sharks, are of considerable economic value and popular interest.
Sharks share much of the evil reputation of snakes. True enough, fatalities from sharks are definitely established for several species, and even for local waters. A tombstone in the Boulton Street Cemetery, Wellington, records the death of a soldier killed by a shark many years ago in Lambton Harbour, and other cases are in the records; but in fact attack by sharks is relatively rare, even in Australian waters where the risk is less than any other violent danger to which the average citizen of that country is exposed. The majority of sharks are of small size, harmless to man, predators on fish, crabs, molluscs and other small life in the sea. Our largest shark, the basking shark, is as harmless as a whale. If people could appreciate the difficulties in establishing records of actual attacks on man by sharks, the common fear of the shark would be greatly diminished, and we would come to a better recognition of their place and value. In various parts of the world these fishes form the basis of a profitable industry. In Florida it is now recognised that the sharks taken in shallow waters are only the stragglers from the great shark populations which live in 500 fathoms and more. The future scope of shark industries is still unmeasured, but the meat of many species is excellent, is now exported, and has been eaten in no small quantity by New Zealanders in recent years; the skins provide excellent ornamental leathers; the livers yield vitamin-rich oils. Dried fins of sharks and rays, and other parts, are exportable, as well as in demand in this country for food. The proper utilisation of these fishes will be an important addition to the fisheries of this country.
At the present time we can recognise some 29 species of sharks and eight, or possibly nine, rays in our waters, the majority being little known and less studied. Unfortunately it is rare for larger specimens, and even page 23 many smaller species, to be brought to the laboratory. They must commonly be studied in the field. Specific distinctness is bold. The species can be readily recognised. In the keys, which are simplified for the local species, attention is directed to individual diagnostic features which can be understood from the study of the common laboratory dogfish. These key features are only a guide to the species. Attention must also be given to the overall form, relative proportions of the head, body, fins, etc.; and to the position and relative size of the fins. Such data can be generally approximated from the figures where guide-lines are marked, and accordingly is not set out in the key in any great detail.
This account aims at facilitating the study of the sharks of these waters by providing a convenient guide. We do not regard it as being either complete or systematically final. It is condensed from extended data based on studies by Archey, Fowler, Phillipps, Whitley, Waite, and others. Fortunately, Bigelow and Schroeder in their recent magnificent work — ‘Fishes of the Western North Atlantic’—have considered the systematic status of many of our sharks and we profit greatly from their studies which provide data for the careful comparison of New Zealand material with the species of their area. Where possible we have reviewed the status of our species, but all the problems are not solved. Decision on the correct generic name of the basking shark — Halsydrus, Tetroras, or Cetorhinus — may better be determined overseas, but it is for the New Zealand worker to settle such problems as the specific identity of many of our species. In reviewing the common spotted dogfish, we find that it was identified by Waite as Squalus fernandinus on the basis of an account by Tate-Regan. Phillipps compared our species with a more recent account of S. fernandinus, found the two distinct, and named ours S. kirki. But S. fernandinus belongs to a group of short-bodied species in the genus Squalus. Our species is elongate, and it is Norman who pointed out that the material Tate-Regan dealt with is elongate and actually belongs to the South American S. lebruni. Norman, comparing specimens from the two areas, could not separate ours from S. lebruni, nor can we at this time distinguish the two. There still seems difficulty about the true mako. Overseas workers favour the opinion that there is only one species, Isurus glaucus, in the Pacific; but Phillipps has given an account of a mako having a more elongate form and with a relatively smaller dorsal. A cast and a specimen in the Dominion Museum gives us no basis for the separation of our Prionace from P. glauca. Fraser-Brunner has now cleared up points in Whitley's account so that we can recognise our hammerhead as Sphyrna lewini. Specimens of Dalatias from Cook Strait are identical with D. licha. We are unable to distinguish juvenile bramble sharks fished in Cook Strait from Echinorhinus brucus.
In general there is need for the examination of much further material for nearly all species, and the results from such work will have considerable ichthyological value. The greater part of our shark fauna is made up of cosmopolitan species, sharks which are apparently from deeper waters. page 24 A careful study of one or more such species here, remote from areas where these fish are better known, will be a significant contribution to the study of the morphological stability of widely distributed species, and may not prove systematically sterile. Current literature gives the present-day worker a tremendous advantage over pioneer and more recent students of the group. It is hoped that this guide will revive interest and lead to an earnest attempt to examine and describe available and new material.
Where possible, the figures used here have been drawn from specimens. It is the practice to always figure the left aspect of animals so that comparison between figures is simplified. In re-drawing from some authors and casts it has been necessary for us to reverse the figure to maintain this standard. Figures have been re-drawn from authors as follows: Archey, 34; McCoy, 44; McCulloch, 10; Morton, 2; Phillipps, 39; Whitley, 24, 30. The following are based on casts in the Dominion Museum: 18, 19, 20, 22, 23, 25, 26, 27, 31, 35. In this guide the reference numbers, e.g. 1 (10) in the key below, are alternatives. Where there is not agreement with 1 refer to 10. Where the agreement is with 10, then proceed to the next number, i.e. 11, etc.
Key to the Lesser Chordates and Major Groups of Fishes
| 1 |
(10) The body simple, not divided into the usual head with well-formed eyes, etc., and trunk of many segments, but as follows: |
| 2 |
(7) Body consisting of a proboscis (prb.), a collar (coll.) and a trunk of few or many segments. |
| 3 |
(4) With many tentacles. Proboscis flattened to a disc surrounded by marginal tentacles rising from the collar; 1 pair, or no gill-slits; trunk U-shaped, the anus near the mouth. (Pterobranchia — regarded by some as non-chordate.) Cephalodiscus sp. (Fig. 1). Included here on the basis of a sub-spherical gelatinous test with numerous erect tubes. Colour, clear yellowish-brown. Reputed to have been collected from the Cook Strait cable. (We record also that Mr. G. Stuckey found a larva of a Phoronis in the waters of Wellington Harbour.) |
| 4 |
(3) Lacking tentacles about the mouth. Proboscis somewhat acorn-like; collar cylindrical; body elongate, worm-like; 5 or more pairs of gill-slits; anus terminal. (Enteropneusta.) |
| 5 |
(6) Dorso-lateral genital wings (g.w.) developed; up to 40 pairs of gill-slits. Balanoglossus australiensis (Hill) 1895. (Fig. 2.) In shallow burrows in fine sand at low tide levels; yellowish, brown and creamy white. Up to 200 mm. Known from Auckland area, and possibly Christchurch on the basis of a larval specimen taken near the latter. page 25 |
| 6 |
(5) Genital wings lacking; few (12) gill-slits; a groove along the proboscis. Saccoglossus otagoensis (Benham) 1899. (Fig. 3.) Among coralline seaweed, holdfasts of kelp, etc. Bright red to orange. Up to 40 mm. and more. Common Wellington to the south. |
| 7 |
(2) No proboscis or collar; body not worm-like. |
| 8 |
(9) The body commonly U-shaped; enclosed in a gelatinous test which may be more or less transparent, or opaque and leathery; sedentary or pelagic; solitary or colonial. Tunicata. A large, diverse group requiring separate treatment.
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Text Figure: Representative Tunicata |
| 9 |
(8) Body straight, naked, compressed, pointed at each end, with many distinct segments; gonads serial. Cephalochorda. Represented here by Epigonichthys hectori (Benham) 1901. (Fig. 4.) Having the gonads developed on the right side only; caudal fin short, not attenuated; approximately 84 myotomes. Length, 50 mm. Low tide levels, burrowing in sand. North Island. page 26 |
| 10 |
(1) A well-formed distinct head usually with well-developed eyes moved by muscles; the mouth either surrounded by a disc or with opposable jaws supported by skeletal elements; a trunk of many segments and a segmented postanal tail; 14 pairs or less of gill-slits; gonads not segmental in the adult; etc. Craniata. |
| 11 |
(16) The mouth surrounded by labial folds which extended may form a disc or contracted are more or less vertical; the folds armed or not with teeth; tongue, protrusible, toothed; a single median nostril; eel-like but without scales or paired appendages. Cyclostomata. |
| 12 |
(15) Snout with barbels; labial folds not toothed; eyes vestigial, concealed; nostril terminal; no separate dorsal fin. |
| 13 |
(14) One pair of external branchial apertures placed one on either side of the midventral line. (Myxinidae.) Myxine biniplicata Richardson and Jowett 1951. (Fig. 5.) Hagfish. Unique in the possession of short ventrolateral paired fins alongside and forward from the branchial apertures; pinkish-white. Not slimy. Up to 16 inches. Trawled in Cape Campbell area. |
| 14 |
(13) Gill-pouches open separately so that there are several (5 to 14) apertures spaced out on either side. (Eptatretidae.) Eptatretus cirrhatus (Bloch and Schneider) 1801. (Fig. 6.) Blind eel. Compressed; 7 pairs branchial apertures. Common in Cook Strait and to the north. Copious slime. Up to 27 inches. Edible. |
| 15 |
(12) Snout without barbels; nostril remote from rim of well-developed oral disc; eyes functional; separate dorsal fins; 7 pairs of branchial apertures. (Mordaciidae.) Represented here by Geotria australis Gray 1851. (Fig. 7.) Lamprey. Edible. Spawned in sandy patches along river margins, develops to a toothless ammocoetes larva½ in. in length, and metamorphoses at 3 to 4 inches to a toothed, large-eyed macrophthalmia which moves downstream to the sea. Returns to freshwater as a velasia stage of 20 inches which matures to the adult, possibly without feeding and in the male with an increase in diameter of the oral disc and the formation of a large pouch below the throat. The teeth vary in these different stages. |
| 16 |
(11) Mouth more or less transverse and supported by jaws; paired pectoral and pelvic appendages generally present. Gnathostomata. |
| 17 |
(24) Paired appendages present as fins which have a web wholely supported by fibres of ectodermal origin; endoskeleton cartilaginous; gill-slits, 7 pairs or less. Chondrichthys. |
| 18 |
(21) Gill-slits concealed beneath a fleshy fold so that there is but one external aperture (as in bony fish); four pairs of gills; adult skin lacks denticles; dorsal spine and fin both depressible. Holocephali. |
| 19 |
(20) Snout extended and supporting a flexible flap-like lobe; pectorals nearly reaching pelvics; lateral line, a closed tube excepting for numerous apertures. page 27Callorhynchus milii Bory 1823. (Fig. 8.) Elephant fish. Very common. Edible. Up to 40 inches. In our material the pectoral barely reaches to the pelvics and falls short of second dorsal differing thus from C. callorhynchus. |
| 20 |
(19) Snout obtusely angled; no distinct anal fin; caudal filamentous butshort, longer in young; lateral line, an open groove. Chimaera novae zealandiae Fowler 1910. (Fig. 9.) Ghost shark. Exceeds 2 feet. |
| 21 |
(18) 5 to 7 pairs of gill-slits opening separately at the surface; dorsal spine (if present) and fin not depressible. Elasmobranchii. |
| 22 |
(23) Gill-slits ventral; body more or less strongly depressed (flattened from above); anterior margin of pectoral fused with head to form a disc Batoidei (skates and rays). |
| 23 |
(22) Gill-slits lateral; pectoral fin with a free anterior margin. Selachii (sharks). |
| 24 |
(17) Web of fins supported by segmented rays; skeleton of bone; gill-slits open into a common branchial chamber covered with a fleshy flap supported by a bony operculum. Osteichthys. (Bony fishes.) A large and diverse group requiring separate treatment. |
Key to the Skates and Rays (Batoidei)
| 1 |
(4) Disc narrow, the width less than half of total length; nasoral grooves short or absent; usually 2 dorsals; caudal well-developed. |
| 2 |
(3) Pectorals not reaching to end of snout (F. Rhinobatidae); first dorsal well behind ventrals; front nasal valves confluent forming a quadrangular flap across front of mouth. (Trygonorrhina fasciata Muller and Henle 1841. (Fig. 10.) Fiddler ray. Up to 4 feet. Doubtfully a member of our fauna: but a shovel-nose Aptychotrema banksii has also been listed here, so one may occur in our waters.) |
| 3 |
(2) Pectorals extend to end of snout (F. Platyrhinidae); one dorsal fin; rostral cartilages absent; nasal flap triangular but deeply incised: above, everywhere thorny. Arhynchobatis asperrimus Waite 1909. (Fig. 11.) Known only from (?) one specimen, Bay of Plenty. 26 inches. |
| 4 |
(1) Disc broad, the width half or more of total length; nasoral groove well developed. |
| 5 |
(10) Teeth raptorial; skin smooth; disc depressed, rounded, anteriorly obtuse; well-developed electric organs (F. Torpedinidae). |
| 6 |
(7) 2 dorsals; tail short; disc large, subcircular; pelvic fins not united (G. Torpedo); no fringe on margin of spiracle; base of first dorsal ends even with base of ventral. Torpedo fairchildi Hutton 1872. (Fig. 12.) Electric skate. Up to 40 inches. (In the literature as Narcacion, Narcobatus, Notastrape, and T. fusca.) page 28 |
| 7 |
(6) 1 dorsal; front portion of pelvics modified as for walking, posterior portion fused to disc; eyes rudimentary. (G. Typhlonarke.) |
| 8 |
(9) Disc circular, the outline broken only by notch under tail; tail short; pelvics short, blunt, not reaching to margin of disc. T. aysoni (Hamilton) 1902. (Fig. 13.) Numb-fish, cramp-fish. Up to 3 feet. Possibly not north of Cook Strait. |
| 9 |
(8) Disc obtuse anteriorly, elongate, not notched below caudal; pelvics short, blunt, but reach to or beyond margin of disc; peduncle little compressed. T. tarakea Phillipps 1929. (Fig. 14.) Up to 13 inches. Possibly not north of Cook Strait. |
| 10 |
(5) Teeth pavement-like; disc broad, angular or rounded. |
| 11 |
(14) Pelvis transverse; usually two small dorsals with rays, but caudal membranous and more or less imperfect (F. Rajidae); rostral cartilage elongate; teeth small, numerous. (G. Raja.) |
| 12 |
(13) Body largely roughened, smooth patches small; a single row of major vertebral spines only on the tail with a minor row on each side also in older specimens; tail slender, long, its length reaching from origin to beyond eyes. R. nasuta Muller and Henle 1841. (Fig. 15. Disc spines not shown.) Skate. Up to 30 inches. (Shows greater variation than yet described.) |
| 13 |
(12) Body with large smooth patches; snout not greatly extended, but sharp pointed; a single row of major vertebral spines with as many as 2 minor rows on each side of tail; tail stout, short, its length barely reaching from its origin to eyes. R. lemprieri Richardson 1846. (Fig. 16.) Skate. Up to 5½ feet. (Possibly the R. australis of Macleay, 1881, since N.Z. specimens have the more pronounced acute rostrum and other features of Macleay's species.) |
| 14 |
(11) Pelvis arched anteriorly; one dorsal, or none; tail slender, lacking rayed fins, whip-like. |
| 15 |
(16) Teeth broad, molar-like, the medians commonly the wider; disc transverse, lateral angles acute (F. Myliobatidae); snout and head smoothly rounded; teeth in 7 rows; first dorsal origin at the length of its
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Plate I |
| 16 |
(15) Teeth small, pavement-like; no horn-like processes at sides of head; disc as wide as long (F. Dasyatidae), quadrangular; tail with a serrated spine (G. Dasyatis). Sting-rays, the serrated spine causing a deep and potentially dangerous wound. |
| 17 |
(18) Tail short (subequal to length of disc), heavy, compressed; tip of serrated spine reaching beyond mid-point of tail; ventral fold on tail, deep; tail armoured on sides with wellspaced dises each bearing an erect conical sharp spine; a row of a few large spaced-out spined plates anterior to serrated spine but not extended far on to dorsum of disc. D. brevicaudatus (Hutton) 1875. (Fig. 18.) Growing to 14 feet long in Australia, but known here to 8 feet. |
| 18 |
(17) Tail long (equals 1½ times length of disc), slender, the terminal portion cylindrical; serrated spine anterior on tail and not reaching to midpoint in length of tail; ventral fold, narrow; tail armoured with crowded discs generally contiguous, and each bearing an erect conical sharp spine; a row of large spined plates anterior to serrated spine extends on to disc, with a row on either side. D. thetidis Waite 1899. Known here to 10 feet long, but a larger specimen estimated 11 feet long taken by the ‘Maimai’ in Cook Strait in 1951. |
Key to the Main Groups of Sharks (Selachii)
| 1 |
(8) Anal fin present. |
| 2 |
(5) 6 or 7 gill apertures; only one dorsal fin. |
| 3 |
(4) Margin of gill-openings lateral, not extending across throat; upper teeth notably dissimilar from lower on either side of symphysis. Notidanoidea. |
| 4 |
(3) Margin of gill-openings extend beneath and across the throat; teeth of upper and lower jaws similar; elongate, rather eel-like. Chlamydoselachoidea. Rare. Not as yet known from our waters. |
| 5 |
(2) Only 5 gill openings; 2 (rarely 1) dorsal fins. |
| 6 |
(7) A stout spine in front of each dorsal fin; teeth near symphysis in each jaw markedly smaller and differing from those toward the corners. Heterodontoidea. (Possibly represented here by Heterodontus portus jacksoni (Meyer) 1793, having the anal base less than twice its length from the origin of the subcaudal, and the origin of the first dorsal above the middle of the base of the pectoral.) |
| 7 |
(6) No spines before the dorsal fins; median teeth basically similar to laterals. Galeoidea. page 31 |
| 8 |
(1) No anal fin. |
| 9 |
(12) Snout, shark-like, of moderate length, not beak-like, without lateral teeth and barbels. |
| 10 |
(11) Trunk subcylindrical to subtriangular; shark-like; eyes lateral; anterior margin of pectorals not overlapping gill openings. Squaloidea. |
| 11 |
(10) Trunk depressed, skate-like; eyes dorsal; anterior margin of pectorals far overlapping gill openings. Squatinoidea (Apparently not yet known from our waters.) |
| 12 |
(9) Snout elongate, flattened, armed with lateral teeth and bearing a long fleshy barbel. Pristiophoroidea. (Unknown from our waters.) |
Key to the Species of Notidanoidea
| 1 |
(4) 7 gill apertures on each side; head broad; snout broadly rounded. G. Notorynchus. |
| 2 |
(3) No median tooth in the upper jaw. (N. cepedianus (Peron) 1807. Sandy-grey with scattered round black spots; up to 8 feet and more; presence doubtful.) |
| 3 |
(2) A single median tooth in the upper jaw. N. pectorosus (Garman) 1884. (Fig. 19.) Brown above, paler below; upper surface irregularly sprinkled with darker spots or specks; up to 8 feet. (Note: the sharp-snouted, 7-gilled Heptranchias with the horizontal diameter of the eye much greater than the internasal space should be watched for here. The anal commences well under the dorsal in H. perlo but at the rear end of the dorsal in H. dakini.) |
| 4 |
(1) 6 gill apertures on each side. Hexanchus griseus (Bonnaterre) 1780. (Fig. 20.) Cow-shark. Immaculate dark grey to almost black, or with a longitudinal lateral streak; up to 26 feet; sluggish in habit; known from depths of 500 fathoms and more. |
Key to the Species of Galeoidea
| 1 |
(2) Base of the first dorsal fin terminating posterior to origin of pelvic fins. (F. Scyliorhinidae.) Cephaloscyllium isabellum (Bonnaterre) 1788. (Fig. 21.) Carpet-shark; swell-shark; no labial furrows on either jaw; brown above with dark bands alternating narrow and wide; up to 8 feet; can inflate the stomach with water or air. |
| 2 |
(1) Base of first dorsal ends above or well anterior to origin of pelvics. |
| 3 |
(26) Head shaped as usual in sharks; not forming a ‘hammer’. |
| 4 |
(11) Tail strongly lunate; lateral keels on caudal peduncle. |
| 5 |
(10) Teeth large, relatively few (25 to 50); no gill-rakers. (F. Isuridae.) page 32 |
| 6 |
(9) Teeth of upper jaw long, narrow, slender, smooth-edged. |
| 7 |
(8) No lateral denticles on any teeth; first 2 teeth in each jaw more slender and flexuous than the others; 1 keel on side of caudal region. Isurus glaucus Muller and Henle 1841. (Fig. 22.) Mako or blue-pointer. Dark navy-blue above, whitish below; regarded as dangerous; up to 13 feet. (I. mako Whitley is regarded by Bigelow and Schroeder as probably identical with I. glaucus. A cast in the Dominion Museum suggests the atlantic I. oxyrinchus more than I. glaucus.) |
| 8 |
(7) First 2 teeth in each jaw similar to succeeding teeth; teeth mostly with lateral denticles; a secondary lateral keel on anterior part of caudal fin below the peduncular keel. The Lamna whitleyi described by Phillipps, 1935, is possibly separable from L. nasus (Bonnaterre) 1788, and needs careful investigation. (Fig. 23.) Porbeagle. Slate-grey on back and sides; lighter below; up to 10 feet. |
| 9 |
(6) Upper teeth broadly triangular, edges serrate; strongly lunate tail. Carcharodon carcharias (Linn) 1758. (Fig. 24.) White shark. Brown to grey above, white on sides and below; up to 30 feet and larger; regarded as most dangerous. |
| 10 |
(5) Teeth minute, numerous (4 or more to the inch), conic not serrate; gill-rakers present. (F. Cetorhinidae.) Cetorhinus maximus (Gunnerus) 1765. (Fig. 25.) Basking shark. Grey above, paler below; up to 40 feet. The skeleton washed ashore often mistaken for that of a sea-serpent; the gill-rakers, being long, are mistaken for hair. Any specimen should be most carefully checked. (The Australian C. maccoyi which has a relatively longer tail and higher first dorsal may extend here.) |
| 11 |
(4) Caudal not lunate. |
| 12 |
(13) Caudal extended to equal nearly half the total length of the animal. (F. Alopiidae.) Alopias vulpinus (Bonnaterre) 1788. (Fig. 26.) Thresher shark. Grey to black above, white below; up to 25 feet. A. caudatus Phillipps is most doubtfully distinct.
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Plate II |
| 13 |
(12) Caudal considerable less than half of the total length; opening of fifth gill above or behind origin of pectoral. |
| 14 |
(17) Teeth low, mosaic- or pavement-like, small, several series functional. (F. Triakidae.) Nostril not connected to mouth (G. Mustelus). |
| 15 |
(16) Many small white spots; origin of first dorsal immediately posterior to base of pectoral; pectoral reaches middle of first dorsal; third gill-opening the largest. Mustelus lenticulatus Phillipps 1932. (Fig. 32.) Spotted gummy-shark, smooth bound. Grey with many conspicuous small white spots; up to 3 feet. |
| 16 |
(15) Some few light spots; origin of first dorsal well behind axilla; pectoral does not reach middle of first dorsal; first gill-opening, largest. M. antarcticus Gunther 1870. Gummy shark. Grey above, whitish below; up to 3½ feet and more. |
| 17 |
(14) Teeth triangular, compressed, sharp, only 1 (or 2) series functional. (F. Carcharinidae.) |
| 18 |
(21) Spiracles present, may be large or minute; anal base short. |
| 19 |
(20) Caudal peduncle with a low lateral dermal ridge; spiracle minute; snout short; teeth, large, serrate, and tips oblique. Galeocerdo cuvier (Lesueur) 1822. (Fig. 30.) Tiger-shark. Slate-grey, irregular banding on back; up to 18 feet. Even if species of Australasian waters is not the same as elsewhere, it has priority in this name. |
| 20 |
(19) No peduncular dermal ridge; no precaudal pits above or below; teeth with denticles, cusps narrow, oblique and not serrate. Galeorhinus australis (Macleay) 1881. (Fig. 31.) School shark. Grey to brown above, lighter below; up to 6 feet and more. |
| 21 |
(18) Spiracles absent. |
| 22 |
(23) Midpoint of base of dorsal considerably nearer to origin of pelvics than to axilla. Prionace glauca (Linn) 1758. (Fig. 29.) Blue shark. Brilliant blue above, white below; up to 15 feet and more. (P. (syn. Glyphis) mackiei Phillipps is inseparable from P. glaucus.) |
| 23 |
(22) Dorsal anterior, the mid point of the base nearer level of axilla than to level of origin of pelvics; margins of cusps of upper teeth regularly serrate, lowers serrate or smooth. |
| 24 |
(25) Second dorsal smaller than and placed above the anal; apex of first dorsal, acute; cutaneous ridge between dorsals. Carcharhinus brachyurus (Gunther) 1870. (Fig. 27.) New Zealand whaler. Uniformly grey; up to 9 feet. (Recorded previously in our literature as Carcharias and Eulamfa.) |
| 25 |
(24) First dorsal with apex obtuse or rounded; second dorsal larger than and commencing slightly anterior to anal. (? Eulamia lamia. The shark listed under this name in our literature is systematically doubtful. The figure (Fig. 28) after Phillipps is possibly Carcharhinus leucas. The probability is that a page 35 second species of Carcharhinus is present in our waters. It may lack a cutaneous fold between the dorsals.) |
| 26 |
(3) Head expanded laterally to form a ‘hammer’. (F. Sphyrnidae.) Sphyrna lewini (Griffith) 1834. (Fig. 33.) Hammerhead shark. Recorded formerly as S. zygaena. Other species may be present and can be recognised in a different contour of the hammer. |
Key to the Species of Squaloidea
| 1 |
(16) A spine at the front of the base of each dorsal (F. Squalidae). |
| 2 |
(13) Teeth dissimilar in the two jaws. |
| 3 |
(12) Snout short, its length from mouth considerably less than from mouth to origin of pectorals; dermal denticles short, rising from a short broad stem. |
| 4 |
(11) Body shark-like, not strongly compressed and not forming an acute triangle in section. |
| 5 |
(8) Inner corner of pectoral broadly rounded; nostrils oblique; scales pedunculate and with 3 or more strong keels. G. Scymnodon. |
| 6 |
(7) Anterior end of base of second dorsal is posterior to the anterior end of pelvic fin; pectoral fin does not reach to base of first dorsal; dorsal spines concealed. S. sherwoodi Archey, 1921. (Fig. 34.) Dark-brown, lighter below; up to 3 feet. |
| 7 |
(6) Anterior end of base of second dorsal above or close behind anterior end of base of pelvic fin; pectoral nearly reaches to anterior end of base of first dorsal which is situated in the first third of the body-length. S. plunketi (Waite) 1910. (Fig. 35.) Uniform dark-brown; up to 5 feet. |
| 8 |
(5) Inner corner of pectoral angular and somewhat produced; nostrils transverse; scales on trunk leaf-shaped with a strong median keel. G. Centrophorus. |
| 9 |
(10) Dorsals relatively large, base of first dorsal longer than that of second; median erect tooth in lower jaw; some denticles tridentate but without long sharp prongs. C. nilsoni Thompson 1930. (Fig. 36.) Brown above, lighter below; up to 3½ feet; from Kaikoura. |
| 10 |
(9) Dorsals relatively small, base of first as measured from spine shorter than of second; some dermal denticles elongate, narrow and sharp-pronged. C. waitei Thompson 1930. (Fig. 38.) Brownish black; length 13 inches; Kaikoura. (? Juvenile of S. plunketi.) |
| 11 |
(4) Body stout, strongly compressed and an acute triangle in section; spines arise from base of dorsals. Oxynotus bruniensis (Ogilby) 1893. (Fig. 41.) The prickly dogfish; uniform sandy-brown; growing to 2 feet. |
| 12 |
(3) Snout long, its length from mouth nearly reaches from mouth to pectoral origin; dermal denticles trifid, elongate, sharp, rise from a narrow stem; page 36 lower teeth with rounded cusps. Deania kaikourae Whitley 1934. (Fig. 37.) Uniform dark-brown; up to 3½ feet; Kaikoura and Cook Strait. |
| 13 |
(2) Teeth similar in both jaws. G. Squalus. |
| 14 |
(15) First dorsal rises close to axilla. S. griffini Phillipps 1931. (Fig. 39.) Brown, immaculate; up to 3 feet and more; North Island. (Possibly the heavy-bodied S. fernandinus.) |
| 15 |
(14) Anterior margin of nostril with a single point; first dorsal rises well behind axilla; Squalus lebruni (Vaillant) 1888. (Fig. 40.) The spotted dogfish. Greyish with conspicuous white spots; up to 3 feet 6 inches. Still requires complete description. |
| 16 |
(1) Second dorsal, and usually the first, without a spine in front. |
| 17 |
(20) Teeth with only 1 cusp; upper teeth, narrow, raptorial; lower teeth expanded, sectorial. (F. Dalatiidae.) |
| 18 |
(19) Lower teeth erect, triangular, nearly symmetrical, serrate; head truncate; eyes large. Dalatias licha (Bonnaterre) 1788. (Fig. 42.) Black shark. Uniform violet-black or dark-brownish; up to 4 feet 6 inches. D. phillippsi is regarded as inseparable from D. licha, but McCulloch shows a fimbriated rectangular nasal flap which is acutely triangular in D. licha and our specimens. |
| 19 |
(18) Lower teeth strongly asymmetrical, not serrate but having the outer margins notched; head depressed; eyes small; branchial apertures very small; dorsals sub-equal. Somniosus antarcticus Whitley, 1939. (Fig. 43.) The sleeper shark. Inadequately known from one specimen, 8 feet 6 inches long, washed ashore at Macquarie Island, hence possibly in our waters. |
| 20 |
(17) Teeth sectorial in both upper and lower jaws, each tooth with several cusps; snout broad and tapering. (F. Echinorhinidae.) Echinorhinus brucus (Bonnaterre) 1788. (Fig. 44.) The spiny or bramble shark. Purplishbrown, paler below, spotted darker; up to 8½ feet. |
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Plate III
Fig. 31: Galeorhinus australis, and upper and lower teeth. Fig. 32: Mustelus lenticulatus. Fig. 33: Sphyrna lewini, and lateral teeth from upper and lower jaws. Fig. 34: Scymnodon sherwoodi, and venter of snout. Fig. 35: S. plunketi, venter of snout, and lateral teeth upper and lower jaws. Fig. 36: Centrophorus nilsoni, venter of snout and teeth. Fig. 37: Deania kaikourae, venter of snout and tooth. Fig. 38: C. waitei, venter of snout and lower tooth. Fig. 39: Squalus griffini. Fig. 40: S. lebruni. Fig. 41: Oxynotus bruniensis. Fig. 42: Dalatias licha, venter of snout and teeth. Fig. 43: Somniosus antarcticus. Fig. 44: Echinorhinus brucus, venter of snout, tooth and scale.
Accessory figures are drawn to the left of the main figure.