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Congrid Leptocephali in Australasian Waters with Descriptions of Conger wilsoni (Bl. and Schn.) and C. verreauxi Kaup.

The Two Species of Conger in New Zealand Waters

The Two Species of Conger in New Zealand Waters

Two earlier accounts (Castle, 1960, 1963) describe and illustrate four congrid eels which inhabit New Zealand waters, two species belonging to Gnathophis Kaup and two which I have referred to Pseudoxenomystax Breder. There are in this region two further congrids which are much more common, referable to Conger Oken, 1817. Eels of this genus are distinguished from other congrids in having a flat, triangular preorbital bone, a large, upturned upper labial flange, one or two rows of teeth along the maxilla and dentary, the outer row compressed to form a cutting edge, otic bulla absent and ethmoid process cartilaginous (for further details see Kanazawa, 1958, pp. 224–225 and Asano, 1962, pp. 85–86). The two New Zealand species are C. wilsoni (Bloch and Schneider, 1801) and C. verreauxi Kaup, 1856 and agree well with the established diagnosis of Conger. Although Kanazawa (1958, pp. 256–258) has recently given descriptions of these two species, the additional information gathered from a wider range of material warrants description and illustration here. Nothing has been known of the early life history of C. wilsoni and C. verreauxi but among the congrid leptocephali in the present collection there are a number of larvae of C. wilsoni and C. verreauxi and these are also described here.

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Text-fig. 6.—Conger wilsoni (Bloch and Schneider, 1801), 627.5mm total length, Bay of Islands, Dom. Mus. No. 3338: Fig. A, lateral view; Fig. B, dorsal view; Fig. C, lateral view of head; Fig. D, dorsal view of head; Fig. E, upper (left) and lower (right) dentition; Fig. F, left preorbital bone (lateral aspect); Fig. G, caudal skelection of specimen 245.5mm total length, Dom. Mus. No. 2941; Fig. H, glass-eel, 85.0mm total length, Dom. Mus. No. 2942, both of the latter from the Bay of Islands.

Text-fig. 6.—Conger wilsoni (Bloch and Schneider, 1801), 627.5mm total length, Bay of Islands, Dom. Mus. No. 3338: Fig. A, lateral view; Fig. B, dorsal view; Fig. C, lateral view of head; Fig. D, dorsal view of head; Fig. E, upper (left) and lower (right) dentition; Fig. F, left preorbital bone (lateral aspect); Fig. G, caudal skelection of specimen 245.5mm total length, Dom. Mus. No. 2941; Fig. H, glass-eel, 85.0mm total length, Dom. Mus. No. 2942, both of the latter from the Bay of Islands.

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C. wilsoni is a relatively slender eel, seldom reaching more than 1000mm in length, which has 141–149 vertebrae, 36–41 lateral line pores before the level of the vent, dorsal fin-rays 294–330, branchiostegal rays 8–9, a relatively large eye, the horizontal diameter of which is 1.9–3.9 per cent of total length (decreasing slightly in relation to increase in total length), the dorsal fin originating about half the length of the pectoral fin behind the pectoral tip and the teeth on the maxilla and dentary numbering about 45–66; it has a northern distribution in New Zealand, from East Cape northwards, but is also known from Western Australia, South Australia, Tasmania through to southern Queensland; it shows similarities to C. oceanicus (Mitchell, 1814) from the western Atlantic and C. philippinus Kanazawa, 1958, from the western Pacific (see Kanazawa, 1958, pp. 256–257). C. wilsoni is also similar to C. verreauxi, the second species known from New Zealand, but the latter is a much more robust eel, reaching 2,000mm in length, having 157–165 vertebrae, 40–44 lateral line pores before the level of the vent, dorsal fin-rays 331–347, branchiostegal rays 10–11, a small eye 1.2–1.9 per cent of total length, the dorsal fin originating about level with the pectoral tip and teeth on each jaw 35–67; it has an essentially southern distribution in New Zealand from Cook Strait southwards but is taken northwards to the Bay of Islands and along the southeast coast of Australia.

Conger wilsoni (Bloch and Schneider, 1801), Text-fig. 6, A-H
1801. Gymnothorax wilsoni Bloch and Schneider, Syst. Ich., p. 529.
1872. Conger wilsoni (Bl. and Schn.). Castelnau, Proc. Zool. Acclim. Soc. Victoria. 1: 193.
1923. Leptocephalus wilsoni (Bl. and Schn.). Lord, Pap. Proc. R. Soc. Tasmania, p. 64.
1928. Leptocephallus wilsoni (Bl. and Schn.). McCulloch, Mem. Aust. Mus., 5 (1): 65.
1932. Leptocephalus monganius Phillipps, N.Z. Jour. Sci. Tech., 13 (4): 230.
1936. Leptocephalus labiatus (Castelnau). Griffin, Trans. roy. Soc. N.Z., 66: 16, p1. 6, figs. 2, 2a, 2b.
1944. Leptocephalus wilsoni hesperius Whitley, Proc. roy. Soc. N.S.W., p. 25, fig. 1.
1958. Conger wilsoni (Bl. and Schn.). Kanazawa, Proc. U.S. nat. Mus., 108: 256, p1. 1, H, fig. 2, w.

Material Examined: 25 specimens, 69.6mm–627.5mm total lengths; Urupukapuka Island, Bay of Islands; rotenone; February, 1961. Five specimens, 75.0mm–245.5mm total lengths; Uurpukapuka Island, Bay of Islands; rotenone; March, 1960; Dom. Mus. No. 2941. One specimen, 815mm total length; Perirua Peninsula; Dom. Mus. No. 1902. One specimen, 904mm total length (skin and head); Mangonui, Doubtless Bay; Dom. Mus. No. 433 (type of Leptocephalus monganius Phillipps, 1932). One specimen, 245.5mm total length, Dom. Mus. No. 3340, stained in alizarin as a skeletal preparation.

Description: Proportional measurements (in per cent of total length) and counts from 30 specimens: total lengths 69.6mm–815mm, standard 97.4–99.1, head 12.5–16.3, snout 3.2–4.5, eye 1.9–3.9, interorbital 2.1–3.6, upper jaw 4.5–6.4, postorbital 7.7–9.8, branchial aperture 1.1–2.3, branchial interspace 2.1–4.2, pectoral 3.4–5.5, preanal 35.2–40.8, predorsal 19.1–21.9, depth before eye 2.9–5.0, at pectoral origin 4.2–6.9, at vent 4.0–6.0, at midpoint of caudal region 3.1–5.2. Branchiostegal rays 8–9, pectoral rays 16–18, dorsal rays before level of vent 57–65, dorsal rays 294–330, anal rays 229–261, caudal rays 4–5 + 4–5, lateral line pores before level of vent 36–41, vertebrae 141–149.

A slender eel which seldom grows to more than 1,000mm, rounded to oval in section, with the vent always well in front of the midpoint of the body. The head is markedly depressed, especially in smaller specimens, the lips are thick and the eye is large. The dorsal begins distinctly behind the level of the pectoral tip. Olive blue-black above, white, tinged with yellow below, the dorsal and anal fins white with a conspicuous but narrow black margin and the eye with a brilliant silver-green patch above the pupil.

Head sharply conical, conspicuously depressed, in most specimens the jaw muscles bulging upwards so that the head is clearly differentiated from the trunk, short, about 7.5 in total length; snout rather blunt but flattened or depressed dorsally, about 4.0 in head, page 20not projecting noticeably in advance of tip of lower jaw; the latter rounded in ventral view, relatively slender, shovel-like; mouth terminal, slightly oblique, with cleft extending to below posterior margin of pupil and contained less than 3.0 in head; upper lip well-developed, especially anteriorly, beginning a little behind tip of snout, becoming weaker posteriorly; lower lip more strongly developed, also beginning behind tip of lower jaw; tongue strong, pointed, extending forwards to a point halfway between the levels of the anterior and posterior nostrils.

Teeth relatively small, but a little larger anteriorly than posteriorly, most bluntly conical and villiform in smaller specimens, a few sharp and slightly recurved, those on the maxilla and dentary flattened anteroposteriorly with their bases much wider than their tips. Maxillary teeth about 45 in a specimen of 630mm total length, uniserial, forming a sharp cutting edge; a few minute teeth in a second longitudinal row medial to the main row about one-third of the way along the outer row. Premaxillary-ethmoid teeth about as large as those on the anterior extremity of the maxilla, about a dozen in number, forming a narrow, curved patch, about twice as broad as long, which barely shows in advance of the tip of the lower jaw when the mouth is closed. Vomerine teeth in an oval patch, about one-third the length of the maxillary row, much larger anteriorly than those more posteriorly placed and about 30 in number. Teeth on the dentary similar to those on the maxilla but with a few extra teeth in a short row in front as well as a short subsidiary row of about eight teeth medial to the main row.

Anterior nostril terminal, tubular, with the tube directed forwards. Posterior nostril small, oval, placed close to the anterior margin of eye and above the horizontal diameter, usually widely open. Eye subcircular, relatively large, contained more than four times in the postorbital. Fleshy interorbital about equal to eye. Branchial aperture lateral, about equal to eye, having a concave free edge, oblique, with the upper extremity above middle of pectoral base and well in advance of level of lower extremity. Vent not protruding conspicuously into the lateral profile.

Dorsal and anal fins delicate, not high and about equally developed. Dorsal originating about half to two-thirds of the pectoral behind level of pectoral tip. Anal fin not as high as dorsal. Caudal fin continuous with dorsal and anal tips, not abbreviated, pointed. Pectoral elongate-oval in shape, with a rounded posterior margin, originating at about the midlateral level, its base oblique and the fin directed slightly posterodorsally, about equal to cleft of mouth in length.

Lateral line moderately conspicuous but barely raised above lateral surface, arising high on head and reaching midlateral level just posterior to level of vent. Pores simple, minute and visible almost to tail tip. Cephalic sensory pores consisting of one occipital pore; one pore on the upper lip at the level of the anterior margin of eye; a large pore immediately behind and level with corner of mouth; two pores set closely together in a short groove on the anterodorsal tip of snout; one pore in front of, and one behind, base of anterior nostril tube; a minute pore on ventral surface of snout; eight mandibular pores in a curved line from the operculum to the tip of lower jaw. Surface sensory organs on the head indicated in most specimens by a transverse row of minute papillae across nape and a semicircular row in front of pectoral base. Most lateral line pores with minute papillae anterodorsal to them.

Colour in life olive blue-black over the dorsal surface and to a point halfway between lateral line and ventral midline, mostly creamish-white below, sometimes tinged with yellow. Head often with a patch of silver posterior to eye. Iris blue-purple anteriorly and posteriorly with a brilliant crescentic patch of silver green above but this fades rapidly on death. Dorsal and anal fins white with a complete, narrow black margin.

Remarks: The most recent account of Conger wilsoni is that of Kanazawa (1958, pp. 256–257, fig. 2, w, pl. 1, H) who studied four specimens from Australia. My specimens conform essentially with Kanazawa's description but the range of variation in most proportions and counts is greater since there are 30 specimens in the present collection. C. wilsoni does not deepen in the body greatly during growth as does C. verreauxi and remains a slender eel with a cylindrical body very little compressed along the caudal region. C. wilsoni has much more numerous teeth on the maxilla and dentary than does C. verreauxi. At 257mm total length, C. wilsoni has teeth 45/46 on each half of the upper and lower jaw respectively, while at 815mm it has 66/69. This increase with growth is shown graphically in text-fig. 7. Other differences between C. wilsoni and C. verreauxi have already been indicated.

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L. Conger wilsoni (Text-fig. 9, A-C)

Material Examined: Centre d'Océanographie de l'Institut Français d'Océanie Collection (14 specimens): 25.2mm total length, IFO Station D10b, 14° 13′ S, 157° 55′ E, 17/5/60 (0214hrs), S½mO (0.5m net, No. 2 mesh, oblique tow), 0–300 metres; 33.7, 33.9, 81.5, St S.2, 20° 10′ S, 163° 27′ E, 7/6/62, MWT5, H, ca. 95m; 42.1, 43.8, St S.5, 13° 30′ S, 162° 05′ E, 10/6/62, MWT5, H, ca. 95m; 46.7, 49.1, St 7–8, 22° 35′ S, 166° 16′ E, 26/7/62, MWT5, H, ca. 20m; 49.5, St S.7, 10° 48′ S, 159° 00′ E, 12/6/62, MWT5, H, ca. 50m; 74.0, St S.4, 15° 48′ S, 161° 00′ E, 9/6/62, MWT5, H, ca. 95m; 76.8, St P57–5–1, 20° 06′ S, 168° 40′ E 9/9/57 (0030hrs), S½mO, 200m; 86.0, St 56–5–4, 14° 50′ S, 166° 15′ E, 2/11/56 (0045hrs), S½mH, ca. 30m; 89.7, St 56–4–6, 6° 50′ S, 169° 55′ E, 30/9/56 (2324hrs), S½mH,′ ca. 100m; 94.4, St S.l, 21° 45′ S, 165° 10′ E, 6/6/62, MWT5, H, ca. 120m.

Western Australian Museum Collection (1 specimen): 90.3, Accession No. P5167, 47 miles west of West End, Rottnest Island, Western Australia, 24/1/62 (0145–0215hrs), larval net, 37 metres.

Text-fig. 7.—The number of compressed teeth on the left maxilla compared with total length in Conger wilsoni and C. verreauxi.

Text-fig. 7.—The number of compressed teeth on the left maxilla compared with total length in Conger wilsoni and C. verreauxi.

New Zealand Collections (2 specimens): 85.0, Dom. Mus. No. 2942, Bay of Islands, from flank of isolated reef rising from 50 metres on a sandy bottom, March, 1960, rotenone, glass-eel; 100.0, VUW Zoology Dept. Collection, Doubtless Bay, January, 1959, from stomach of snapper, Chrysophrys auratus(Forster).

Description: 17 specimens: total lengths 25.2mm–l00.0mm, myomeres 141–151, dorsal rays 286–317, anal rays 190–261, last vertical blood vessel at myomere 52–56. Description made from a specimen which has almost reached metamorphosis, IFO St S.4 (measurements in mm): total length 74.0, head 4.8, snout 1.4, eye 1.2, cleft of mouth 2.3, postorbital 2.5, pectoral 1.1, snout-vent 64.9, predorsal 45.9, depth before eye 1.4, at pectoral origin 3.0, at midpoint between pectoral and vent 7.0, at vent 4.5. Branchiostegal rays 8, pectoral rays not yet formed, dorsal rays before level of vent 244, dorsal rays 317, anal rays 227, caudal rays 5 + 4. Teeth 1 + 1 + IX + 11 over 1 + XIV Myomeres 116 + 26 = 142. a–d = 46. Last vertical blood vessel at myomere 54.

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Body moderately elongate, much compressed except along head, not deep, the maximum depth about nine times in total length, reducing more gradually in front of the midpoint. Head short, about 14 in total, relatively distinct from trunk; snout blunt, about 3.5 in head, its dorsal profile convex; anterior nostril tube directed forwards, posterior nostril with a simple raised rim and placed above horizontal diameter of eye; eye oval, the greatest diameter vertical, but the horizontal diameter 1.3 in snout; cleft of mouth slightly oblique, extending to below posterior margin of pupil; teeth very acute, barely curved; branchial aperture curved, its ventral margin not yet attached to the lateral surface. Pectoral fin short, about equal to length of snout, almost circular in shape with the fin-rays not developed; dorsal fin low, originating at myomere 70, fin-rays very numerous and closely packed; anal fin similar; caudal pointed.

Pigmentation in formalin consisting of a conspicuous brown to black crescentic patch below the posteroventral margin of the iris; a rounded chromatophore deep in the throat; a paired, ventral, somatic series of about 70 rounded chromatophores following the course of the intestine from the 10th myomere, thence on each segment to the vent; this series continues as scattered chromatophores on the bodywall above the anal fin; a series of minute, irregularly shaped chromatophores on the bases of most of the anal rays; a few on the bases of the dorsal terminal rays; a scattering of minute pigment spots over the base of the caudal fin; chorioid pigment present.

Vertical blood vessels to the viscera numerous, occurring irregularly every four or five segments from about myomere 12 to myomere 54 although this last vessel is the only one that is conspicuous. Gall bladder usually difficult to distinguish.

Remarks: Leptocephali of C. wilsoni are strikingly similar to those of Gnathophis incognitus Castle (1963, p. 43). They have the same elongate form, oval eye, well-developed pectoral, the patch of pigment below the iris, chromatophores on the throat, in a ventral, somatic series from the pectoral region to the vent and on the bases of the anal rays. In C. wilsoni, however, as in other species of Conger, this ventral series continues above the anal fin almost to the tip of the caudal region. This is a characteristic feature which distinguishes Conger leptocephali although very small specimens of about 20mm do not usually have this series developed and consequently may be confused with those of Gnathophis.

It may be suggested that the above collection of C. wilsoni leptocephali contains a number of larvae which could be referred to Conger cinereus cinereus(Rüppell, 1828) since this species has 139–146 vertebrae (Kanazawa, 1958, p. 235) and is common in the central west Pacific as far south as North Queensland and New Caledonia. There are, however, no appreciable differences in these 18 leptocephali which would indicate the presence of two species, and in view of the fact that larvae of C. cinereus cinereus have chromatophores along the midlateral line (Ancona, 1928, p. 38) it is unlikely that this is the case. Nevertheless, a glass-eel collected in the Solomon Islands and in the present collection shows features which are characteristic of C. cinereus cinereus, that is, two cephalic pores behind the eye and the sixth suborbital pore above the level of the corner of the mouth (see text-fig. 9, D). Relevant data for this specimen are as follows:—C.S.I.R.O. Division of Fisheries and Oceanography (Cronulla) Collection: 85.7mm total length, Fairwind collection, Kieta, Bougainville Island, Solomon Islands, 21/10/49, submarine light.

Growth and Metamorphosis

Growth of the leptocephalus of C. wilsoni proceeds much as in Gnathophis, the main difference being the gradual development of a very blunt snout, thick, fleshy lips which are characteristic of the adult, the tube of the anterior nostril becomes directed forwards and not downwards and the anal fin lengthens so that the pigment spots above it increase in number; in Gnathophis there are none of these spots behind the vent.

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Text-fig. 8.—Conger verreauxi Kaup, 1150mm total length, Post Levy: Fig. A, lateral view; Fig. B, dorsal view; Fig. C, lateral view of head; Fig. D, dorsal view of head; Fig. E, upper (left) and lower (right) dentition; Fig. F, left preorbital bone (lateral aspect); Fig. G, caudal skelection.

Text-fig. 8.—Conger verreauxi Kaup, 1150mm total length, Post Levy: Fig. A, lateral view; Fig. B, dorsal view; Fig. C, lateral view of head; Fig. D, dorsal view of head; Fig. E, upper (left) and lower (right) dentition; Fig. F, left preorbital bone (lateral aspect); Fig. G, caudal skelection.

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Geographical Distribution and Location of the Spawning Areas

There are insufficient larvae in the present collection to indicate a precise spawning area but the larvae are clearly smallest north of New Caledonia. One specimen collected in Western Australia at 90.3mm has reached metamorphosis, while a single glass-eel and the largest larva in the collection were taken off northern New Zealand. The absence of very small larvae in collections from these areas suggests that C. wilsoni spawns well to the north of its area of adult distribution.

Conger verreauxi Kaup, 1856 (Text-fig. 8, A-G)
1856b. Conger verreauxi Kaup, Arch. Naturg., 22 (1): 72.
1870. (non) Conger vulgaris Cuvier. Gunther, Cat. Fish. Brit. Mus., 8: 39.
1872. (non) Conger vulgaris Cuvier. Hutton, Cat. Fish. N.Z., p. 66, pl. 11, fig. 105.
1892. (non) Conger vulgaris Cuvier. Thomson, Trans. N.Z. Inst., 24: 214.
1896. (non) Conger vulgaris Cuvier. Jordan and Evermann, Bull. U.S. nat. Mus., 47: 355.
1911. (non) Leptocephalus conger (L.). Waite, Rec. Canterbury (N.Z.) Mus., 1: 164.
1921. (non) Leptocephalus conger (L.). Phillipps, N.Z. Jour. Sci. Tech., 4: 119 and 125.
1921. (non) Leptocephalus conger (L.). Thomson, Hist. Portobello Fish. Hatch., p. 71.
1921. (non) Conger ?wilsoni (B1. and Schn.). Waite, Rec. S. Aust. Mus., 2 (1): 49, fig. 74.
1922. (non) Leptocephalus conger (L.). Phillipps, N.Z. Jour. Sci. Tech., 5: 94.
1923. (non) Conger ?wilsoni (Bl. and Schn.). Waite, Fishes of S. Aust., p. 72.
1923. (non) Leptocephalus conger (L.). Lord, Pap. Proc. R. Soc. Tasmania, p. 64.
1929. Leptocephalus labiatus (Castelnau). McCulloch, Mem. Aust. Mus., 5 (1): 65.
1932. Leptocephalus labiatus (Castelnau). Phillipps, N.Z. Jour. Sci. Tech., 13: 229.
1936. Leptocephalus verreauxi (Kaup). Griffin, Trans, roy. Soc. N.Z., 66 (1): 15, pl. 6, figs. 1, la.
1958. Conger verreauxi Kaup. Kanazawa, Proc. U.S. nat. Mus., 108: 257.
1962. Leptocephalus ?wilsoni (Bl. and Schn.). Scott, Mar. freshw. fish Sth. Aust., p. 75.

Material Examined: One specimen, 261.0mm total length; Bay of Plenty; stomach of groper, Polyprion oxygeneios (Bl. and Schn.), caught in 180 fathoms; Dom. Mus. No. 2032. One specimen, 329.1mm; Pegasus Bay, trawl; 27/9/54; Dom. Mus. No. 1617. One specimen, 799.3mm; Porirua Harbour, Wellington; handlined in 3–4 fathoms; 20/3/59. Four specimens, 1056mm–1148mm; Port Levy; commercial trawl in 10 fathoms by Ikatere; 29/3/60. One specimen, 1200mm; Big Bay, South Westland; crayfish pot in 5 fathoms; March, 1959. Three specimens, 1316mm–1597mm; off Oaro, Kaikoura; handlined; 17/12/58; Dom. Mus. No. 2672. One specimen, 1317mm; off Castlepoint; trawl; 19/8/53; Dom. Mus. No. 1384. One specimen, 1391mm; three miles south of Titahi Bay, Wellington; handlined in 5 fathoms; 11/6/60. One specimen, 1540mm; Cape Brett, Bay of Islands; handlined in 20 fathoms; 19/2/61. One skull, Dom. Mus. No. 889.

Description: Proportional measurements (in per cent of total length) and counts from the above 14 specimens: total lengths 261.0mm–1597mm, standard length 98.6–99.6, head 13.1–16.1, snout 3.0–4.5, eye 1.2–1.9, interorbital 1.5–3.5, upper jaw 4.2–5.8, postorbital 7.6–10.3, branchial aperture 1.2–2.5, branchial interspace 2.1–6.4, pectoral 4.6–6.3, preanal 36.4–43.5, predorsal 17.2–21.8, depth before eye 2.7–4.9, at pectoral origin 3.8–8.1, at vent 3.6–8.6, at midpoint of caudal region 2.7–5.5. Branchiostegal rays 10–11, pectoral rays 17–18, dorsal rays before level of vent 56–70, dorsal rays 331–347, anal rays 238–265, caudal rays 5 + 4, lateral line pores before level of vent 40–44, vertibrae 157–165.

Body massive in most specimens but distinctly slender in small examples of less than about 600mm; usually growing to about 1500mm but occasionally reaching 2000mm. In page 25these large specimens the anterior part of the body is broad and powerful, swollen at the belly, but the head is depressed and the eye small. The lips are very thick, the branchial aperture gapes widely and the pectoral is very broad and flap-like. The vent is always in front of the midpoint of the body and the dorsal and anal fins, in large specimens, are very strongly developed to give a bladelike, compressed caudal region. The colour is variable, usually dull grey-black above, often mottled with light grey or cream and lighter below; small specimens have a black margin to the median fins. This eel usually lives in deep rock crevices, moving out to feed at night although it may be encountered foraging in broad daylight. It is an aggressive creature which may inflict deep gashes with its powerful jaws and sharp teeth.

Head bluntly conical, depressed, not conspicuously differentiated from trunk, short, about 7.0 in total length; snout blunt, flattened dorsally, about 4.0 in head, not projecting in advance of tip of lower jaw; the latter rounded in ventral view, strong, shovel-like; mouth terminal, slightly oblique with cleft extending to below posterior margin of pupil and contained 3.0 times in head; upper lip very well developed, especially along its anterior half, beginning a little behind tip of snout and weaker posteriorly; lower lip thicker, overlapping lower jaw, beginning a little behind tip of lower jaw; tongue strong, pointed, extending to a point halfway between levels of anterior and posterior nostrils.

Teeth relatively small but robust, generally larger anteriorly than those more posteriorly placed; most of them bluntly conical and villiform in small specimens, but a few on premaxillary-ethmoid and anterior part of vomer sharp and recurved, the main teeth on the maxilla and dentary flattened anteroposteriorly with wide bases. Maxillary teeth about 48 in a specimen of 1150mm total length, uniserial, forming a sharp, powerful cutting edge; a row of about 24 minute teeth forming a second longitudinal row medial to this main row; a small triangular patch of about 18 teeth outside the most anterior part of the maxillary row. Premaxillary-ethmoid teeth mostly large, about 20, forming a curved patch, twice as broad as long, which barely shows in advance of lower jaw when mouth is closed; the most anterior teeth of this patch minute. Vomerine teeth large anteriorly but much smaller posteriorly, about 30 in number, forming a tear-shaped patch, less than one-third the length of the maxillary patch with the broad end anterior. Teeth on the dentary essentially in two longitudinal rows of which the lateral row contains about 50 teeth, similar to those on the maxilla; those of the medial row are minute but about the same in number; a few teeth are placed outside the main row in a short row of about five teeth at the anterior tip of the dentary.

Anterior nostril terminal, tubular, with the tube directed forwards and equal in length to about half the pupil. Posterior nostril small, placed close to anterior margin of eye and above the horizontal diameter, usually widely open, oval. Eye oval, small, about 5.5 in postorbital. Fleshy interorbital broad, about twice diameter of eye. Branchial aperture lateral, 1.5 times eye, widely open, with a concave free edge and slightly oblique, its upper extremity near middle of pectoral base. Vent protruding a little into the lateral profile.

Dorsal and anal fins delicate in small specimens but thick and fleshy in large individuals, the dorsal somewhat higher than the anal. Dorsal originating less than the diameter of the pupil behind the level of the pectoral tip, reaching its greatest height in the last quarter of the caudal region where it equals the depth of the body at that point. Anal similar to the dorsal. Caudal fin continuous with the tips of the dorsal and anal fins and pointed. Pectoral fan-like, thick, fleshy and deep in larger specimens, about equal to length of cleft of mouth, its base oblique.

Lateral line ridge inconspicuous, arising high on the head and curving down to meet the midlateral level well behind level of vent. The pores are simple, minute and visible almost to caudal tip. Cephalic sensory pores as in C. wilsoni, that is, an occipital pore, five pores on tip of snout and around base of anterior nostril, two pores on maxilla, one behind corner of mouth, three on opercular region and six on lower jaw. Specimens of about 600mm or less may show a pattern of minute surface sensory papillae across the dorsal surface of the head, in front of the pectoral base and around the nostrils.

Colour in life generally dark grey or brown to blue-black above, light grey to white below on the abdomen but specimens may sometimes be mottled grey and white. Small specimens have a narrow black margin to the dorsal and anal fins. Iris dull silver.

Remarks: The specimens of C. verreauxi examined above conform well with Kanazawa's redescription (1958, pp. 257–258) of the species from the type and one other specimen in the British Museum. The eye in the present 14 specimens is slightly larger at 1.2–1.9 per cent of total compared with 1.1 in the two specimens examined by Kanazawa. None of the specimens examined above have a small tentacle on either side of the snout as oted by Phillipps (1932, p. 229) but this author may have repeated an observation made by Castelnau (1879, p. 399) on the type of his Conger ?labiata from Sydney. There was possibly some confusion page 26in Castelnau's mind with the projecting, tube-like anterior nostril, if indeed his specimen was a Conger. The "belly and fins of a bright yellow" would be an unusual colouration for either C. verreauxi or C. wilsoni, both of which are known from south-east Australia; the type of C. labiata therefore may well belong to some other genus of eels, perhaps Ophichthus.

Proportional Changes During Growth: In C. verreauxi, after reaching about 500mm, there is a marked increase in the depth of the body along the trunk so that specimens of about 1500mm may be extremely large in girth. There is at the same time a very great increase in weight and large C. verreauxi may be 351b–401b. Related to this, the branchial interspace increases much more rapidly than any other proportion of the body. The branchial aperture also lengthens very rapidly. The largest specimen of C. verreauxi examined (1597mm) is about six times the length of the smallest specimen (261mm) and comparing the two specimens, the increases in the various proportions are as follows:—head 6.8, snout 7.7, eye 4.6, interorbital 8.5, upper jaw 8.1, postorbital 7.3, branchial aperture 11.3, branchial interspace 11.2, pectoral 7.0, preanal 6.8, predorsal 7.3. The eye therefore decreases in size relative to the length of the body as growth proceeds while the head and preanal length increase at about the same rate relative to the length of the body.

A conspicuous change during growth in both C. verreauxi and C. wilsoni is an increase in number of the compressed teeth along the maxilla and dentary (for comparative data see Kanazawa, 1958, fig. 2). At a length of 261mm, C. verreauxi has 35/36 teeth on the maxilla and dentary respectively. The numbers increase regularly with growth and reach a maximum of about 63/65 at 1200mm total length. This increase is illustrated in text-fig. 7. and compared with the numbers of compressed teeth in C. wilsoni. The difference in number of teeth on the maxilla or dentary provides a valuable character for the separation of the two species although at lengths up to 200mm there is insufficient difference in the numbers to distinguish examples of the two species on this character alone.

Food: C. verreauxi feeds on a great variety of marine animals including fish, Crustacea and cephalopods. The stomach of a specimen taken at Big Bay, South Westland, contained two scarlet parrot-fish, Pseudolabrus miles (B1. and Schn.), a part of a blue-cod, Parapercis colias (Forster), part of a crayfish, Jasus lalandii and two octopus tentacles. On the west coast of the South Island and around Wellington C. verreauxi is known to enter crayfish pots to feed on captured crayfish, as well as to attack crayfish in rocky crevices.

Leptocephalus Conger verreauxi

Material Examined: Centre d'Océanographie de l'Institut Français d'Océanie Collection (5 specimens): 24.1mm total length, IFO Station S.5, 13° 30′ S, 162° 00′ E, 10/6/62, MWT5, H, ca. 70m; 32.8, St S.3, 18° 10′ S, 162° 00′ E, 8/6/62, MWT5, H, ca. 95m; 75.2, St 56–5–3, 15° 45′ S, 166° 27′ E, 31/10/56 (2248hrs), S½mO, ca. 150m; 130.5, St 57–6–5, 23° 29′ S, 166° 11′ E, 11/10/57, S½|mO, ca. 100m, sample 10; 139.0, St S 1m 1, 10 miles west of Bulari Pass, New Caledonia, 30/10/61, 1.0m plankton net, H, ca. 67m, sample 1.

C.S.I.R.O. Division of Fisheries and Oceanography (Cronulla) Collection (1 specimen): 107.5, Warreen Station 105/39, 41° 17′ S, 148° 26′ E, 10/4/39, N100, H, surface, 30mins.

Description: Six specimens: total lengths 24.1mm–139.Cmm, myomeres 160–165, dorsal rays 286–317, anal rays 190–261, last vertical blood vessl at myomere 52–56. anterior margin of gall bladder at about myomere 55. Description made from the Warreen Station 105/39 specimen (measurements in mm): total length 107.5, head 6.6, snout 2.0, eye 1.4, cleft of mouth 3.0, postorbital 3.6, pectoral 2.0, snout-vent 85.5, predorsal 58.3, depth just before eye 3.0, at pectoral origin 4.0, at midpoint between pectoial and vent 8.0, page 27
Text-fig. Figs. A-C, L. Conger wilsoni, 74.0mm total length, IFO Station S.4: Fig. A, lateral view; Fig. B, lateral view of head; Fig. C, tip of caudal region. Fig. D, glass-eel of Conger cinereus (Ruppell, 1828), 85.7mm total length, DFO (Cronulla) Collection, Kieta, Bougainville Island, Solomon Islands. Figs. E-H, L. Scalanago lateralis Whitley, 1935, 60.2mm total length, Warreen Station 36/48 (Cronulla): Fig. E, lateral view; Fig. F, lateral view of head; Fig. G, lateral view at about myomere 54; Fig. H, tip of caudal region.

Text-fig. Figs. A-C, L. Conger wilsoni, 74.0mm total length, IFO Station S.4: Fig. A, lateral view; Fig. B, lateral view of head; Fig. C, tip of caudal region. Fig. D, glass-eel of Conger cinereus (Ruppell, 1828), 85.7mm total length, DFO (Cronulla) Collection, Kieta, Bougainville Island, Solomon Islands. Figs. E-H, L. Scalanago lateralis Whitley, 1935, 60.2mm total length, Warreen Station 36/48 (Cronulla): Fig. E, lateral view; Fig. F, lateral view of head; Fig. G, lateral view at about myomere 54; Fig. H, tip of caudal region.

page 28 at vent 8.3. Branchiostegal and pectoral rays hard to distinguish, dorsal rays before level of vent 197, total dorsal rays 336, anal rays 263, caudal rays 6 + 5. Teeth 1 + VI + 16 over 1 + VI + 10 Myomeres 107 + 57 = 164. a–d = 36. Last vertical blood vessel at myomere 54.

Body moderately elongate, much compressed except along head, shallow, its maximum depth near level of vent about 13 in total length, reducing much more rapidly behind vent. Head short, about 16 in total, relatively distinct from trunk; snout very blunt, short, 3.3 in head, its dorsal profile convex; nostrils separated, the anterior one a short tube directed forwards and with a complete rim, the posterior one with a simple raised rim and placed just in front of eye; eye oval, its greatest diameter vertical, but the horizontal diameter 1.4 in snout; cleft of mouth slightly oblique, extending to below posterior margin of pupil; teeth very acute, in three series in the upper jaw and in the lower. Pectoral short, equal to snout in length; dorsal fin relatively well-developed with clearly observable fin-rays; anal similar; caudal with well-developed hypurals and rays.

Pigmentation in formalin as follows:—a small crescentic patch of brownish pigment above the iris and a larger, more conspicuous crescentic patch below the pupil; two small, somatic chromatophores behind the branchial aperture; a paired, ventral, somatic series of rounded chromatophores following the course of the intestine from the 8th segment to the vent, at intervals of one or two segments; this series continues above the base of the anal fin as a rather widely spaced series along the caudal region; a stellate chromatophore on the base of every third or fourth anal ray; a scattering of chromatophores over the base of the caudal fin; chorioid pigment present.

Vertical blood vessels to the viscera numerous, beginning at about the 5th myomere with a barely visible vessel, then continuing irregularly to the 54th myomere.

Remarks: The leptocephali described above are typical of Conger larvae in having a paired, ventral, somatic series of chromatophores along the level of the intestine to the vent, a crescentic patch of pigment on the oval eye and a series of chromatophores above the anal fin. They agree well in number of myomeres, 160–165, with C. verreauxi which is the only species of Conger with more than 160 vertebrae. The hypurals are elongated and similar in shape to those of the adult, although in the specimen described the caudal rays differ slightly in number from the number normally observed in the adult. Leptocephali of C. verreauxi differ essentially from those of C. wilsoni in having a greater number of myomeres, in conformity with the difference in myomeres of the adults, i.e. 160–165 in C. verreauxi compared with 141–151 in C. wilsoni. Larvae of C. verreauxi reach a greater length when full-grown than do those of C. wilsoni (140mm compared with 100mm). Spawning of C. verreauxi probably takes place well to the north of New Caledonia on the evidence of the distribution and size of the leptocephali although this is a remarkably great distance from the geographical limits of the essentially southern C. verreauxi.

L. Scalanago lateralis Whitley, 1935 (Text-fig. 9, E-H)
1935. Scalanago lateralis Whitley, Rec. Aust. Mus., 19 (4): 218, fig. 2.

Material Examined: Western Australian Museum Collection (13 specimens): 20.9mm total length, Accession No. P5298, Lancelin, 34 miles west of West End, Rottnest Island, Western Australia, 3/7/62 (0030–0100hrs), N70, surface; 38.9, P5282, 42 mls, 21/6/62 (0300hrs), larval net, 37 metres; 39.7, P5538, 45 mls, 10/10/62 (0150hrs), N70, surface; 41.8, P5299, 34 mls, 3/7/62 (0030–0100hrs), N70, surface; 43.2, P5536, 45 mls, 10/10/62 (0010hrs), N70, surface; 44.2, P5180, 49 mls, 1/8/61 (0500–0530hrs), N70, surface; 46.1, P5242, 19 mls, 4/4/62 (0230hrs), N70, surface; 53.0, P5297, 34 mls, 3/7/62 (0300–0100hrs), N70, surface; 53.0, P5159, 50 mls, 11/9/61 (2345–2415hrs), N70, surface; 56.3, P5540, 44 mls, 10/10/62 (0230hrs), N70, surface; 56.7, P5535, 22 mls, 20/9/62 (0215hrs), In, 37m; 57.0, P5171, 30 mls, 25/10/61 (2250–2320hrs), In, 27m; 57.5, P5548, 30 mls, 24/10/62 (0320hrs), In, 110m.

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C.S.I.R.O. Division of Fisheries and Oceanography (Cronulla) Collection (3 specimens): 48.2, Warreen Station 37/48, 28° 48′ S, 113° 36′ E, 2/9/48, N70, H, surface, 15mins; 55.2, 60.2, St 36/48, 28° 48′ S, 113° 47′ E, 1/9/48, N70, H, surface, 15mins. All three specimens from Western Australia.

Description: 16 specimens: total lengths 20.9mm–60.2mm, myomeres 112–119, dorsal rays 121–149, anal rays 198–240, a–d = 35–37, last vertical blood vessel at myomere 52–56, anterior margin of gall bladder at myomere 16–18. Description made from the largest specimen which is probably full-grown, Warreen Station 36/48 (measurements in mm): standard length 59.3, head 4.2, snout 1.9, eye 0.9, cleft of mouth 2.3, postorbital 2.1, pectoral 1.6, snout-vent 45.8, predorsal 24.1, depth before eye 1.9, at pectoral origin 3.2, at midpoint between pectoral and vent 7.8, at vent 7.4. Dorsal rays 233, dorsal rays before level of vent 148, anal rays 144, caudal rays 4 + 3. Teeth 1 + VI + 7 over 1 + VIII + 5 Myomeres 76 + 38 = 114. a–d = 36. Last vertical blood vessel at myomere 54, anterior margin of gall bladder at myomere 18.

Body moderately elongate, compressed, deep, the maximum depth 7.0 in total, reducing evenly in front of, and behind, midpoint of body. Head relatively long, 12.0 in total, not greatly differentiated from trunk; snout acute, about 3.0 in head, its dorsal profile slightly convex; both nostrils well separated, the anterior nostril carried on the end of a short tube; eye oval, 2.0 in snout; cleft of mouth slightly oblique, extending to below posterior margin of pupil; teeth moderately acute. Pectoral long, a little longer than snout, elongate-oval; dorsal and anal fins well-developed with clearly defined fin-rays, the dorsal origin well in advance of the level of the vent; caudal relatively pointed.

Pigmentation in formalin or alcohol consisting of a paired, regular, ventral series of rounded, somatic chromatophores following the course of the gut from the pectoral every two or three segments to the vent; a crescentic patch of pigment below the iris; rather more widely spaced chromatophores along the base of the dorsal than the more closely set series on the anal base, with a scattering of pigment on the caudal base; a midlateral series of large, constantly dendritic chromatophores (none rounded in any specimen seen) from the pectoral to the tip of the caudal region, spaced at every two or three segments anterior to the level of the vent but more widely spaced posteriorly, each chromatophore with many fine, thread-like branches radiating from a compact centre.

Remarks: The leptocephalus described above agrees in the arrangement of pigmentation and general morphology with L. congroides Ancona, 1928, from the Red Sea but this species has 169 myomeres compared with 112–119 of the present material, and Ancona's species has no dendritic major lateral chromatophores. Scalanago lateralis Whitley, 1935, an unusual congrid eel from New South Wales, South Australia and Western Australia has 116–119 branches to the unique ladderlike pattern along the lateral line, 180+ dorsal fin-rays, 150+ anal rays and 8 caudal rays. The various counts from the leptocephalus described above and Scalanago lateralis agree so well that I am satisfied the larvae are identifiable with this species. The leptocephalus has a restricted distribution since it is known only from collections made in Western Australia and this agrees well with the distribution of the adult. The number of relatively small larvae in the collection indicates spawning in Western Australian waters.

Leptocephalus laureus n.sp. (Text-fig. 10, A-C)

Material Examined: Centre d'Océanographie de l'Institut Français d'Océanie Collection (6 specimens): type, 72.9mm total length, IFO Station S lm 6, 10 miles west of Bulari Pass, New Caledonia, 30/11/61, 1.0m plankton net, H, ca. 120m, sample 6; 46.1, St 7–8, 22° 35′ S, 166° 16′ E, 26/7/62, MWT5, H, ca. 20m; 57.4, St S.6, 11° 51′ S, 159° 13′ E, 11/6/62, MWT5, H, ca. 95m; 63.2, St P58–1–10 (45–2), 21° 10′ S, 166° 45′ E, 20/1/58 (0045hrs), S½mH, 50m; 75.9, St S.l, 21° 45′ S, 165° 10′ E, 6/6/62, MWT5, H, ca. 120m; one damaged specimen, St LL 61–1–1, 20° 30′ S, 163° 23′ E, 8/3/61, stomach of lancet fish, Alepisaurus ferox.

Description: Six specimens: total lengths 46.1mm–75.9mm, myomeres 104–111, dorsal rays 133–174, anal rays 92–139, a–d = 13–14, last vertical blood vessel at myomere 34–40, anterior margin of gall bladder at myomere 22–24. Description made from the type, an almost full-grown specimen IFO Station S lm 6 (measurements in mm): standard length 72.2, head 5.9, snout 2.0, eye 1.0, cleft of mouth 2.3, postorbital 3.0, pectoral 1.3, snout page 30
Text-fig. 10.—Figs. A-C, Leptocephalus laureus n. sp., type, 72.9mm total length, IFO Station S lm 6: Fig. A, lateral view; Fig. B, lateral view of head; Fig. C, tip of caudal region. Figs. D-F, Leptocephalus stenorhynchus n. sp., type, 66.8mm total length, IFO Station S.5: Fig. D, lateral view; Fig. E, lateral view of head; Fig. F, tip of caudal region. Figs. G-I, Leptocephalus trilineatus n. sp., type, 44.0mm total length, IFO Station 7–6: Fig. G, lateral view; Fig. H, lateral view of head; Fig. I, tip of caudal region.

Text-fig. 10.—Figs. A-C, Leptocephalus laureus n. sp., type, 72.9mm total length, IFO Station S lm 6: Fig. A, lateral view; Fig. B, lateral view of head; Fig. C, tip of caudal region. Figs. D-F, Leptocephalus stenorhynchus n. sp., type, 66.8mm total length, IFO Station S.5: Fig. D, lateral view; Fig. E, lateral view of head; Fig. F, tip of caudal region. Figs. G-I, Leptocephalus trilineatus n. sp., type, 44.0mm total length, IFO Station 7–6: Fig. G, lateral view; Fig. H, lateral view of head; Fig. I, tip of caudal region.

page 31 vent 59.5, predorsal 51.0, depth before eye 2.4, at pectoral origin 4.8, at midpoint between pectoral and vent 16.4, at vent 10.8. Dorsal rays 174, dorsal rays before level of vent 85, anal rays 139, caudal rays 6 + 4. Teeth 1 + 1 + IX + 13 over 1 + XI + 5 Myomeres 74 + 33 = 107. a–d = 14. Last vertical blood vessel at myomere 38, anterior margin of gall bladder at myomere 24.

Body elongate-oval, much compressed, very deep, the maximum depth 4.1 in total, reducing equally in front of, and behind, the midpoint of the body. Head relatively long, about 12.0 in total, clearly differentiated from trunk; snout bluntish, 3.5 in head, its dorsal profile convex; anterior nostril tubular and directed forwards, well separated from the posterior nostril which is placed just in front of eye; eye oval, 2.0 in snout; cleft of mouth slightly oblique and reaching below middle of pupil; teeth moderately acute. Pectoral oval, equal to snout; dorsal and anal fins well-developed, especially posteriorly; caudal rounded.

Pigmentation consisting of a paired, ventral series of about 12 somatic chromatophores from the level of the pectoral to the level of the last vertical blood vessel which is placed halfway along gut; a line of five spots on the throat; a crescentic patch of pigment below the iris; a few spots on the bases of some anal rays. (L. laureus = relating to the laurel, in reference to the laurel-leaf shape of the body.)

Remarks: The ventral series of pigment spots and the crescentic patch of pigment below the eye suggests that this leptocephalus belongs with the Congrinae, but I cannot further identify the species. Considering that the larvae of the shallow water genera Gnathophis and Conger are known and that the myomeres are very low in number for a congrid eel, precluding the identification of the species with such long-tailed forms with elongated hypurals as Uroconger and Promyllantor, I can suggest only that L. laureus may belong to an unknown deep-water congrid. The number of myomeres is lower than that recorded for any known congrid eel.

Leptocephalus stenorhynchus n.sp. (Text-fig. 10, D-F)

Material Examined: Centre d'Océanographie de l'Institut Français d'Océanie Collection (8 specimens): 23.3mm total length, 47.3, 66.8 (type), 76.0, IFO Station S.5, 13° 30′ S, 162° 05′ E, 10/6/62, MWT5, H, ca. 95m: 34.5, St 7–2, 22° 35′ S, 166° 16′ E, 17/7/62, MWT5, H, ca. 70m; 41.0, 45.1, St S.6, 11° 51′ S, 159° 13′ E, 11/6/62, MWT5, H, ca. 95m; 55.9, St 7–8, 22° 35′ S, 166° 16′ E, 26/7/62, MWT5, H, ca. 20m.

Description: Eight specimens: total lengths 23.3mm–76.0mm, myomeres 134–152, dorsal rays 167–185, anal rays usually poorly developed, a–d = 43–46, last vertical blood vessel at myomere 47–51, anterior margin of gall bladder at myomere 26–28. Description made from the type, a 66.8mm specimen, IFO Station S.5 (measurements in mm): standard length 65.5, head 4.6, snout 2.0, eye 0.8, cleft of mouth 2.7, postorbital 2.4, pectoral 1.0, snout-vent 63.0, predorsal 50.4, depth before eye 1.6, at pectoral origin 3.1, at midpoint between pectoral and vent 8.6, at vent 2.8. Dorsal rays 175, dorsal rays before level of vent 148, only terminal anal rays developed, caudal rays 4 + 3. Teeth 1 + 1 + IV + 8 over 1 + V + 5 Myomeres 130 + 12 = 142. a–d = 45. Last vertical blood vessel at myomere 49, anterior margin of gall bladder at myomere 28.

Body elongate, but not excessively so, compressed, deep, the maximum depth about 7.0 in total length. Head relatively long, about 13.0 in total, distinct from trunk; snout acute, long, 2.5 in head, its dorsal profile slightly concave, never convex; nostrils set closely together immediately in front of eye; eye oval, its horizontal diameter 2.5 in snout; cleft of mouth slightly oblique, relatively long, reaching to below posterior margin of eyeball; teeth acute. Pectoral oval, 1.5 in snout; dorsal weakly developed; anal fin very short; caudal rounded.

Pigmentation in the form of a paired, ventral series of up to 70 compact, somatic chromatophores from below the pectoral origin every segment (anteriorly) or every 3–4 segments (posteriorly) to the vent; a line of five spots on the throat; a crescentic patch of pigment below the iris and a minute patch above the eyeball; scattered spots on the bases of the anal rays and over the base of the caudal. (Gk. stenos = narrow, rhynchos = snout,

Remarks: The most characteristic feature of this species is the elongate, acute in reference to the narrow, beak-like snout.) snout which is not found in other congrid leptocephali. The ventral series of chromatophores and crescentic patch below the eye shows that this species belongs page 32in the Congrinae but again I have no suggestions to make as to the identity of the adult. The broad hypurals and moderate number of vertebrae indicate that the adult would probably not possess a long tail as found in Uroconger, Promyllantor and other similar genera.

Leptocephalus trilineatus n.sp. (Text-fig. 10, G-H)

Material Examined: Centre d'Océanographie de l'Institut Français d'Océanie Collection (2 specimens): type, 44.0mm total length, IFO Station 7–6, 22° 35′ S, 166° 16′ E, 26/7/62, MWT5, H, ca. 50m; 122.6, St LL 57–5–4, 21°33′ S, 166° 31′ E, 11/9/57, stomach of lancet fish, Alepisaurus ferox.

C.S.I.R.O. Division of Fisheries and Oceanography (Cronulla) Collection (2 specimens): 21.9, Warreen Station 26/40, 32° 34′ S, 152° 55′ E, 20/4/40, N100, O, 0–200m; 29.3, St 200/39, 30° 19′ S, 153° 33′ E, 16/7/39, N100, O, 200m.

Description: Four specimens: total lengths 21.9mm–122.6mm, myomeres 186–199, last vertical blood vessel at myomere 57–59. Description made from the type, a 44.0mm specimen, IFO Station 7–6 (measurements in mm): standard length 43.8, head 2.9, snout 1.0, eye 0.7, cleft of mouth 1.1, postorbital 1.1, pectoral 1.2, snout-vent 42.1, predorsal 33.5, depth before eye 1.6, at pectoral 2.1, at midpoint between pectoral and vent 4.1, at vent 0.7. Fin-rays not developed. Teeth 1 + 0 + VII over 1 + IV Myomeres 163 + 36 = 199. Last vertical blood vessel at myomere 59.

Body elongate, compressed, depth 10.0 in total. Head relatively long, 14.0 in total, not conspicuously differentiated from trunk: snout short, 3.5 in head, its dorsal profile slightly convex; nostrils not yet differentiated but the olfactory organ set in the middle of snout; eye oval, 2.0 in postorbital or 1.3 in snout; cleft of mouth oblique, reaching to below middle of pupil, teeth acute. Pectoral fin round to oval, 1.5 in snout, median fins inconspicuous.

Pigmentation consisting of a paired ventral series of rather diffuse somatic chromatophores from the pectoral region to the vent; about three pigment spots on the throat; a minute patch of pigment above the eyeball and a crescentic patch below it; a regular series of large, diffuse chromatophores following the midlateral level from the pectoral to the tip of the caudal region, spaced at about every two to three segments; an irregular line of diffuse chromatophores above and below this midlateral line; a scattering of larger chromatophores on the caudal tip. (L. tres = three, linea = a line, in reference to the three lines of chromato phores on the lateral surface.)

Remarks: This larva is immediately distinguishable from all other congrid leptocephali in having three longitudinal lateral rows of chromatophores. It also has a high number of myomeres for congrid larvae as well as a narrow caudal (although the three specimens described are clearly not full-grown) which would probably possess elongated, narrow hypurals. This suggests that the adult would be a long-tailed congrid but further identification is at present not possible.

Leptocephalus geminus n.sp.

Material Examined: Centre d'Océanographie de l'Institut Français d'Océanie Collection (5 specimens): type, 40.9mm total length, IFO Station D1b, 20° 56′ S, 163° 46′ E, 11/5/60 (2033hrs), S½mO, 0–300m; 115.3, St LL 61–1–2, 20° 50′ S, 163° 38′ E, 8/3/61, stomach of lancet fish, Alepisaurus ferox; 64.9, St S lm B, 10 miles west of Bulari Pass, New Caledonia, 28/11/61, 1.0m plankton net, H, ca. 90m, sample 5; 69.2, St MWT B, 10 miles west of Bulari Pass, New Caledonia, 28/11/61, MWT3, H, ca. 67m, sample 4; 29.0, St S.5, 13° 30′ S, 162° 05′ E, 10/6/62, MWT5, H, ca. 95m.

C.S.I.R.O. Division of Fisheries and Oceanography (Cronulla) Collection (1 specimen): 29.2, Warreen Station 16/38, 33° 40′ 20″ S, 151° 27′ 30″ E, 2/.9/38, N200H, 25m, 30mins.

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Description: Six specimens: 29.0mm–115.3mm total lengths, myomeres 160–174, last vertical blood vessel at myomere 49–56, anterior margin of gall bladder at myomere 35–36. Description from the type, a 40.9mm specimen, IFO Station Dlb (measurements in mm): head 3.3, snout 1.4, eye 0.8, cleft of mouth 1.6, postorbital 1.6, pectoral 1.2, snout-vent 39.8, predorsal ca. 29.3, depth before eye 1.9, at pectoral origin 2.3, at midpoint between pectoral and vent 5.3, at vent 1.1. Dorsal rays 224, other rays not developed. Teeth 1 + 1 + I + 8 over 1 + I + 6 Myomeres ca. 136 + 31 = ca. 167. a–d = ca. 48. Last vertical blood vessel at myomere 52. Anterior margin of gall bladder at myomere 35.

Body moderately elongate, much compressed, a little deeper behind the midpoint where the depth is 7.7 in total length and from here tapering gradually towards snout, more rapidly towards caudal tip, the latter turned downwards; vent subterminal in this specimen; pigmentation mainly as a paired series of chromatophores along the level of intestine and three longitudinal rows of chromatophores on the lateral surface.

Head short, 12 in total, not clearly differentiated from trunk; snout short, 2.4 in head, its dorsal profile concave, the nasal organ conspicuous but the nostrils as yet undeveloped; eye oval, 1.6 in snout; cleft of mouth oblique, extending to below middle of pupil. Teeth acute but generally short; the first on each jaw a forwardly-directed needle-like fang, that of the upper jaw placed on anterodorsal aspect of snout; the second of upper jaw very small, less acute, flatly triangular in section with the apex lateral; the third tooth much larger but similar in shape to the second; the remaining eight teeth similar, small, gradually increasing in size towards angle of mouth; those of the lower jaw decreasing slightly in size from the second to the last but generally larger than those of upper jaw. Pectoral a large, fleshy flap, 1.5 times longer than eye; dorsal fin with faint but nevertheless countable basal structures, originating well in advance of vent.

Pigmentation as follows:—a narrow, crescentic patch of pigment above iris and a larger, more conspicuous but also more diffuse patch below iris; three round, compact chromatophores in a line on the lateral aspect of throat; a paired, ventral series of rather diffuse, rounded, somatic chromatophores from below pectoral base along level of intestine as far as vent, a little fewer than one per segment; a series of more diffuse somatic chromatophores slightly below middle angle of myomeres from the 5th segment to the tip of caudal region, spaced at about one chromatophore per 2–4 segments (but rather irregularly spaced); a second longitudinal, lateral series of diffuse, somatic chromatophores between this midlateral row and the dorsal flexure of the myomeres, much more infrequently placed than those of the midlateral row; a similar but still more infrequently spaced row of chromatophores along the ventral flexure of the myomeres; pigment in the chorioid. (L. geminus = a twin, in reference to the close similarity of this species to Leptocephalus trilineatus.)

Remarks: The group of specimens described here is clearly very similar to the previous species in pigmentation, that is, in the possession of three longitudinal rows of chromatophores on the lateral surface of the body. Other pigmentation is typical of the larvae of various congrid eels (the ventral series along the level of the intestine and the presence of iris pigment). The present specimens, however, have fewer myomeres (160–174) than the previous species and the last vertical blood vessel is placed a little further forwards (at myomere 49–56 compared with myomere 59 in the previous species). I am satisfied that these specimens represent a distinct species, especially in view of similar distinctions between the leptocephali of say, Ariosoma scheelei and A. mauritianum. There are two species to which L. geminus may possibly be referred, if only on the basis of myomere counts and the structure of the caudal. These are Pseudoxenomystax bulbiceps (Whitley, 1948) known from Tasmania to the Chatham Islands in deep water and P. hirsutus Castle, 1960, known from Kaikoura and Cook Strait, New Zealand (see Castle, 1960, pp. 465 and 467). Both of these species have about 160 vertebrae and a relatively narrow tail the hypurals of which are elongated and support about eight caudal rays, similar to the condition in L. geminus. Dorsal rays in these two species are between 300 and 350 in number, an appreciably higher number than in the largest specimen of L. geminus. However, in this specimen the dorsal rays are poorly developed and would clearly be more numerous in the metamorphosed eel. In a single, very large specimen of L. geminus from the northeast Indian Ocean which I have examined, the dorsal fin-rays have reached their full number (indicated by the abrupt origin of the dorsal fin) of about 260 but unfortunately in page 34this specimen the tail tip is missing and a correct count cannot be made. Nevertheless, I would estimate that there would be a full complement of not less than 300 fin-rays in the undamaged larva and consequently I would tentatively suggest L. geminus to be the young of one of the above species of Pseudoxenomystax. If this were the case then a second species of this genus, as represented by L. trilineatus with more numerous myomeres is also suggested.

Leptocephalus mediopunctatus n.sp. (Text-fig. 11, A-C)

Material Examined: Centre d'Océanographie de l'Institut Français d'Océanie Collection (3 specimens): type, 73.0mm total length, IFO Station 57–4–3, 20° 50′ S, 166° 50′ E, 31/7/57 (0045hrs), S½mH, ca. 50m; damaged specimen, St 56–4–3b, 18° 07′ S, 168° 22′ E, 18/5/56 (2310hrs), S½mH, ca. 90m; ca. 118 (damaged), St LL 59–1–3, 22° 45′ S, 162° 44′ E, 30/1/59, stomach of lancet fish, Alepisaurus ferox.

Description: From the type, a 73.0mm specimen (measurements in mm): standard length 72.7, head 4.1, snout 1.2, eye 0.9, cleft of mouth 1.9, postorbital 2.0, pectoral 1.0, snout-vent 70.2, predorsal 27.1, depth before eye 1.9, at pectoral origin 3.2, at midpoint between pectoral and vent 8.2, at vent 1.6. Fin-rays not developed. Teeth 1 + 1 + III + 8 over 1 + IV + 5 Myomeres 189 + 54 = 239. a–d = 142. Last vertical blood vessel at myomere 62. Anterior margin of gall bladder at myomere 60.

Body relatively elongate, much compressed, its maximum depth 8.9 in total length; vent subterminal in this specimen; pigmentation inconspicuous, restricted mainly to a line of small, somatic chromatophores on the midlateral line and another along the level of the intestine from the pectoral to the vent.

Head short, about 18 in total, not conspicuously differentiated from trunk; snout blunt, 3.4 in head, its dorsal profile convex and the nasal organ well developed; eye oval, 1.3 in snout; cleft of mouth oblique, reaching to below middle of pupil; teeth moderately acute, conspicuous. Pectoral round, relatively short, about equal to eye; dorsal origin well in advance of level of vent at the level of the 47th myomere; rays of dorsal and anal fins not well enough developed to be counted but probably about 300; caudal fin weak with the hypurals and rays undifferentiated.

Pigmentation consisting of a curved, narrow patch above iris and a larger, more readily noticeable crescentic patch below iris on its posteroventral corner; a line of five, small, compact spots on the lateral wall of the throat, lateral to the heart; a paired ventral series of small, somatic chromatophores spaced at about one per segment at the level of the intestine from the 6th myomere to the vent (although these spots are much less frequent near the vent); a midlateral series of small, diffuse or compact, somatic chromatophores, about one per segment, from the 8th segment to about the level of vent; three minute spots slightly in advance of the caudal tip; chorioid pigment present. (L. medius = the middle, punctum, = a point, in reference to the longitudinal row of chromatophores along the middle of the body.)

Remarks: The present species bears close resemblances to the leptocephali of Conger conger (L.) and C. cinereus Rüppell in having a midlateral line of chromatophores, one per segment, as well as an intestinal series and a patch of pigment below the iris (these last two also being typical characters of members of the Congrinae). However, the number of myomeres in the present species is much greater than in any known species of Conger (the highest being that found in C. verreauxi Kaup, 165–172). I find only one species of Leptocephalus which approaches the present material in number of myomeres, pigmentation and other characters; this is L. magnaghii Ancona, 1928, from the Red Sea, having 209–219 myomeres and lateral chromatophores spaced at every two segments. While I do not place great emphasis on the latter difference, I am satisfied that the difference in number of myomeres between the present specimens (the two other New Caledonia larvae have about 235 myomeres) and L. magnaghii is great enough to indicate a second species. With regard to the identity of the adult of L. mediopunctatus, only one congrid eel is recorded to have more than 200 vertebrae; this is Uroconger lepturus (Richardson, 1844), an elongated congrid eel which is known from Japan to South Africa and which has recently been redescribed by Asano (1962, pp. 114–117, fig. 49). This species has 203–204

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Text-fig. 11.—Figs. A-C, Leptocephalus mediopunctatus n. sp., type, 73.0mm total length, IFO Station 57–4–3: Fig. A, lateral view; Fig. B, lateral view of head; Fig. C, tip of caudal region. Figs. D-G, L. hyoproroides Strö mman, 1896, 48.8mm total length, IFO Station S.4: Fig. D, lateral view; Fig. E, lateral view of head; Fig. F, lateral view of posterior portion of intestine to show kidney and pigmentation; Fig. G, tip of caudal region.

Text-fig. 11.—Figs. A-C, Leptocephalus mediopunctatus n. sp., type, 73.0mm total length, IFO Station 57–4–3: Fig. A, lateral view; Fig. B, lateral view of head; Fig. C, tip of caudal region. Figs. D-G, L. hyoproroides Strö mman, 1896, 48.8mm total length, IFO Station S.4: Fig. D, lateral view; Fig. E, lateral view of head; Fig. F, lateral view of posterior portion of intestine to show kidney and pigmentation; Fig. G, tip of caudal region.

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vertebrae and an almost filamentous tail with narrow hypurals. It could therefore be suggested that L. magnaghii Ancona is referable to U. lepturus since the former has 209–219 myomeres and rather narrow hypurals indicating that the caudal tip in the adult would probably be attenuated. Should this identification prove correct then a second species of Uroconger, to which L. mediopunctatus may be referred, is probably present in the Indo-Pacific. However, whether or not these suggestions may be confirmed must await examination of Uroconger for vertebral counts on a worldwide basis.

Leptocephalus hyoproroides Strömman, 1896 (Text-fig. 11, D-G)
1896. L. hyoproroides Strömman, Lept. Univ. Mus. Upsala, pp. 39–41, pl. 4, figs. 5 and 6.
1936. L. hyoproroides Strömman. Bertin, Bull. Inst, océanogr. Monaco, 694: 5–6, figs. 5–7.

Material Examined: Centre d'Océanographie de l'Institut Français d'Océanie Collection {10 specimens): 13.6mm total length, IFO Station D5, 18° 32′ S, 159° 50′ E, 14/5/60 (0820hrs), S½mO (0.5m net, No. 2 mesh, oblique tow), 0–300m; 26.8, St D15b, 9° 50′ S, 159° 20′ E, 22/5/60 (0219hrs), S½mO, 0–300m; 55.4, St MWT 3 I (sample 4), 10 miles west of Bulari Pass, New Caledonia, 1/8/61, MWT3, H, ca. 40m; 45.5, St S.l, 21° 45′ S, 165° 10′ E, 6/6/62, MWT5, H, ca. 120m; 42.7, 45.8, 48.8, St S.4, 15° 48′ S, 161° 00′ E, 9/6/62, MWT5, H, ca. 95m; 61.1, St S.5, 13° 30′ S, 162° 05′ E, 10/6/62, MWT5, H, ca. 95m; 37.1, St S.6, 11° 51′ S, 159° 13′ E, 11/6/62, MWT5, H, ca. 95m; 55.1, St 7–2, 22° 35′ S, 166° 16′ E, 17/7/62, MWT5, H, ca. 70m.

Description: 10 specimens: total lengths 13.6mm–61.1mm, myomeres 110–122, dorsal rays (2 specimens) 331 and 346, anal rays (2 specimens) 286 and 236, caudal rays (2 specimens) 5 + 3 and 4 + 3, a–d = 23–28, last vertical blood vessel at myomere 42–48, anterior margin of gall bladder at myomere 7–10. Description made from an almost fullgrown specimen, IFO Station S.4 (measurements in mm): total length 48.8, standard 47.8, head 3.9, snout 1.3, eye 0.6, cleft of mouth 1.8, postorbital 2.1, pectoral 1.5, snout-vent 19.2, predorsal 7.9, depth before eye 1.4, at pectoral origin 3.1, at vent 12.2, at midpoint of caudal region 9.7. Fin-rays as in the second specimen above, dorsal rays before level of vent 107. Teeth 1 + 1 + V + over 1 + 10 Myomeres 41 + 71 = 112. a–d = 27. Last vertical blood vessel at myomere 46. Anterior margin of gall bladder at myomere 10.

Body elongate-oval, much compressed except along head, deep, the maximum depth about four times in total length, tapering about evenly in front of, and behind midpoint. Head relatively long, about 12.5 in total, clearly differentiated from trunk; snout moderately blunt, 3.0 in head, its dorsal profile barely convex; both nostrils well separated on a conspicuous nasal organ; eye oval, twice in snout; cleft of mouth extending to below middle of pupil, slightly oblique; teeth moderately acute. Pectoral oval, a little longer than snout; dorsal origin well in advance of level of vent; anal long; caudal with well developed broad hypurals and fin-rays.

Pigmentation in formalin as follows:—a small, compact chromatophore at the base of each tooth of the anterior group of seven teeth on the maxilla and the posterior nine on the dentary; six compact chromatophores on temporal region; three postorbital spots; two oblique preopercular rows of eight and five chromatophores respectively; 10 in a group in front of pectoral base; five spots in a row on the lateral aspect of the throat, this row merging into a paired, ventral, somatic series of about two minute chromatophores per segment; this series bifurcates at the level of the gall bladder to form two rows of minute spots, one a somatic series of about one spot per segment to the vent, the other a splanchnic series above intestine of about three spots per segment; a conspicuous row of compact or diffuse spots slightly in advance of each myoseptum, as well as on the lateral body wall above and below the muscle segments; a row of chromatophores on the anal base; a few spots on the base of the posterior portion of the dorsal; scattered spots over the surface of the caudal; a small, crescentic patch of pigment below the posteroventral corner of the iris; a minute patch above the anterodorsal corner of the iris; pigment in the chorioid.

Remarks: The ten specimens of the distinctive leptocephalus described above show remarkably close resemblances to the single specimen of L. hyoproroides described by Strömman (1896, p. 39) from southwest of Bermuda. In his redescription of Strömman's type specimen, Bertin (1936, p. 5) gives a myomere count of 38 + 76 = 114 and these figures are within the range of myomeres in page 37the present specimens from the waters of New Caledonia (38–45 + 65–79 = 110–120). The pigmentation of these specimens exactly coincides with that of Strömman's with the addition of the patch of pigment above and below the iris (a character not apparently observed by either Strömman or Bertin but one which may easily be overlooked). In view of these similarities I therefore have no hesitation in referring my specimens to L. hyoproroides. Schmidt (1913, p. 55) also re-examined the type of L. hyoproroides and states that a leptocephalid (58mm total length) collected from Thor Station 156 in the Mediterranean can be referred to the same species and identifies L. hyoproroides as the young of Chlopsis bicollaris Rafinesque (Nettastomidae). Although both Ancona (1928, p. 112) and Bertin (1936, p. 6) refer Strömman's species to C. bicollaris, following Schmidt, they are clearly in error, since larvae of the latter species have 130–140 vertebrae and the lateral pigment restricted to a midlateral row. Despite resemblances in the distribution of pigment along the level of the intestine, the structure of the hypurals and the anterior position of the vent, I believe the presence of the patches of pigment above and below the iris in the present specimens from New Caledonia to be a sufficiently reliable character by which to refer L. hyoproroides to the Congridae and not to the Nettastomidae. L. hyoproroides has large pectoral fins while the young and adults of Chlopsis bicollaris lack pectorals. Although Schmidt believes this to be no barrier to the identification of L. hyoproroides with the Nettastomidae since pectorals may be lost during larval development, in those eels in which the adults lack pectorals (muraenids, various ophichthids) young larvae always have much reduced pectorals but these are lost long before the leptocephalus is full-grown. In having splanchnic pigment above the intestine L. hyoproroides shows some resemblance to members of the Anagoinae.