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Journal of Fish Biology (2004) 64, 1430–1434 doi:10.1111/j.1095-8649.2004.00382.x,availableonlineathttp://www.blackwell-synergy.com

A first record of plutodus in the north-eastern Atlantic

H. ZIDOWITZ*, H. O. FOCK†, C. P USCH AND H. VON W ESTERNHAGEN Alfred Wegener Institute Foundation for Polar and Marine Research, Am Handelshafen 12, 27 570 Bremerhaven, Germany

(Received 13 November 2002, Accepted 6 February 2004)

One specimen ofthe largetooth cookiecutter Isistius plutodus was caught in the north-eastern Atlantic at 43580 N; 28320 W. This is the first record of this rare in the north-eastern Atlantic and the northernmost point ofits known distribution. # 2004 The Society ofthe British Isles Key words: distribution; Isistius plutodus; largetooth ; morphometrics; north-eastern Atlantic.

The Isistius (, ; Shirai, 1992) consists of two recent species, the cookiecutter shark Isistius brasiliensis (Quoy & Gaimard) and the largetooth cookiecutter shark Isistius plutodus Garrick & Springer (Compagno, 1984). Bite marks ofsome 5–7 cm diameter in large fishes and marine mammals are indicators ofthe presence of Isistius spp. Isistius brasiliensis is a frequently caught shark in tropical and subtropical regions in all oceans. No fresh ‘crater wounds’ on potential prey have been found north of 33500 N(Mun˜ oz-Chapuli et al., 1988). Isistius plutodus is very rare and only known from a few localities in the subtropical Atlantic and Pacific Oceans; it was originally described from a single specimen caught off the coast of Alabama, U.S.A. (Garrick & Springer, 1964). Parin (1975) reported a second specimen from off the coast of Okinawa, Japan (25110 N; 128300 E) extending the known distribution into the Pacific Ocean. A third specimen was reported by Golovan & Pakhorukov (1986) at 22520 N off the coast of Western Sahara in the eastern central Atlantic. In 1988, a fourth specimen was reported from off the coast of Brazil (30300 S; 50060 W) by Sadowsky et al. (1988), thus extending the known distribution of I. plutodus to the southern hemisphere. Four more specimens were subsequently received from fisherman in the area (Amorim et al., 1998). McGrouther (2001) gives an account ofanother specimen in the southern hemisphere and the second

*Author to whom correspondence should be addressed at present address: Lappenbergsallee 4B, 20 257 Hamburg, Germany. Tel. and fax: þ49 40 49 95 18; email: [email protected] †Present address: ecoanalysis.de, Ko¨ nigsberger Straße 9, 23 795 Bad Segeberg, Germany. 1430 # 2004 The Fisheries Society ofthe British Isles LARGETOOTH COOKIECUTTER SHARK 1431 north- 0 2 1 2 4 1 0 7 5 5 8 6 7 5 0 7 0 38 0 5 0 0 8 7 6 6 7 417 254 Female Atlantic specimen (this paper) North-eastern Isistius plutodus † .9 .1 .2 .7 .1 .2 .6 .7 .8 .8 0 11 94 92 26 24 27 d d d d d d d d d d 0 8 4 ...... n. d. 363 Female (data from South-western Isistius plutodus Pacific specimen AMS I.28924-001 ZMH 9368 McGrouther, 2001) 0 6n 31 7n 3n 7n 23 2n 81 7n 4n 76 0n 0n 2n 66 17 5 8 8 7 3 4 5 5 n. d. n. d. 270 given as a per cent of total length Female Central eastern Isistius plutodus Atlantic specimen Pakhorukov, 1986) (data from Golovan & . 1 0 19 09 70 42 97 34 21 51 16 06 67 08 58 75 16 d 9 9 7 3 4 7 7 . n. d. Male 335 1975) -holotype and specimens from the central and north-eastern Atlantic, North-western Isistius plutodus Pacific specimen (data from Parin, 0 89 79 60 12 16 04 11 7n 21 16 66 47 38 88 75 48 9 0 9 2 7 4 5 6 Isistius plutodus 15 18 19 68 64 75 86 86 n. d. 423 Female holotype Isistius plutodus GulfofMexico, & Springer, 1964) (data from Garrick ): ): % % ): western and south-western Pacific. Morphological features are % I. Morphometric comparison ofthe (mm) Width Height Outer corner ofnostrils Eye Mouth First gill opening Fifth gill opening Pectoral origin Pelvic origin First dorsal origin Second dorsal origin Upper caudal origin Lower caudal origin First and second dorsal Second dorsal and caudal ABLE T T Trunk at pectoral origin ( L Mass (g) Sex Specimen number in museum USNM 188 386 n. d. Tip ofthe snout to ( Distance between bases (

# 2004 The Fisheries Society ofthe British Isles, Journal of Fish Biology 2004, 64, 1430–1434 1432 H. ZIDOWITZ ET AL. 9 7 7 2 0 5 2 6 5 5 6 8 0 0 0 5 4 5 9 5 6 * þ 6 4 2 1 28 þ 99 .4 .1 .4 .3 .2 .6 .2 .7 .4 .2 .1 .1 .0 .8 .0 84 92 05 63 13 þ d d d d d d d d d d d d d d d 1 ...... n. d. þ 12 99 . n . n . n . n . n . n . n . 4 . n 8n 1n 64 12 25 43 7n 2n 8n 9n 0n þ þ d d d d d d d d d 7 5 4 1 1 ...... þ þ 10 12 89 04 51 95 0n 73 15 6n 23 4n 5n 02 0n 6n 5– –– 7n 4n 21 60 87 91 3n þ þ 6 6 4 7 1 1 þ þ tooth was not discernible. 14 10 98 44 71 64 54 82 55 83 73 52 37 64 08 73 62 73 41 – 70 16 90 51 þ þ 5 2 3 4 3 2 2 3 7 7 3 7 1 1 45 14 14 þ þ 9 14 . T L )3 % )0 )0 )2 % % % ): % ): % ): ): % ): % ): % % Pectoral and pelvic Pelvic and caudal Length base Length posterior margin Height Length base Length posterior margin Height Length base Length anterior margin Width Overall length Length base Length claspers Length dorsal lobe Length ventral lobe Distance between inner corners 1 , no odd numbers ofupper teeth were observed and a symphyseal , mm values converted to per cent of n. d., no data* available or not† given in description ofspecimen. First ( Second dorsal fin ( Pectoral fin ( ( Caudal fin ( No. upper teeth (n) Vertical diameter ofeye ( Horizontal diameter ofeye ( Nostrils ( Length fifth gill opening ( Length first gill opening ( No. lower teeth (n)

# 2004 The Fisheries Society ofthe British Isles, Journal of Fish Biology 2004, 64, 1430–1434 LARGETOOTH COOKIECUTTER SHARK 1433 specimen in the Pacific Ocean caught in 1988 off New South Wales, Australia, c.33000 S; 152000 E. In the present study, a specimen was caught on 3 August 2000 in a pelagic trawl at midnight at a depth of90–100 m over a water depth of890– 980 m, north ofthe Azores (43 580 N; 28320 W). The specimen is located at the Ichthyological Collection ofthe Zoological Institute ofthe University ofHamburg (ZMH 9368). The capture expands the present knowledge ofthe distribution of I. plutodus by 21 degrees to the north in the eastern Atlantic, reaching the northern most point ofits known distribution at 43 580N. The specimen measured 417 mm in total length (LT) and had a fresh mass of254 4 g. Except for the ventral collar, it showed a uniform brown colour. Morphometric measurements according to Bigelow & Schroeder (1948) were compared with the description ofthe holotype specimen from Garrick & Springer (1964) and the specimens caught by Parin (1975), Golovan & Pakhorukov (1986) and McGrouther (2001) (Table I). It appears that there is a considerable vari- ability within the species. Isistius plutodus differs from that of I. brasiliensis mainly in its dentition and morphometric characters. Compared to I. brasiliensis, the lower teeth of I. plutodus are reduced in number and much larger, whereas the upper teeth are reduced in number and shorter. According to Garrick & Springer (1964), the 15 þ 1 þ 15 18 þ 1 þ 18 dental formula in I. brasiliensis is 12 þ 1 þ 12 to 15 þ 1 þ 15 compared to I. plutodus 10 þ 1 þ 10 14 þ 1 þ 14 ranging from 8 þ 1 þ 8 to 9 þ 1 þ 9 (Table I). The dentition ofthe present speci- men refers to the description in that 9 þ 1 þ 9 lower teeth were found. Among the 28 upper teeth no symphyseal tooth was discernible. In contrast to the original description that I. plutodus has no clearly defined black collar over the branchial region, the present specimen, similar to the description given by Parin (1975), had a ventral colouration (Fig. 1).

FIG. 1. Pronounced lower row ofteeth and ventral colouration at the pectorals forthe north-east Atlantic specimen of Isistius plutodus.

# 2004 The Fisheries Society ofthe British Isles, Journal of Fish Biology 2004, 64, 1430–1434 1434 H. ZIDOWITZ ET AL.

Thanks are owed to N. Josten for the translation of Russian literature and anonymous referees for helpful comments on the manuscript.

References Amorim, A. F., Arfelli, C. A. & Fagundes, L. (1998). Pelagic elasmobranchs caught by longliners off southern Brazil during 1974–97: an overview. Marine and Freshwater Research 49, 621–632. Bigelow, H. B. & Schroeder, W. C. (1948). . In Fishes of the Western North Atlantic, Part I. (Tee-Van, J., Breder, C. M., Hildebrand, S. F., Parr, A. E. & Schroeder, W. C., eds), pp. 244–254. New Haven, CT: Sears Foundation for Marine Research, Yale University. Compagno, L. J. V. (1984). FAO species catalogue, Vol. 4. Sharks ofthe world: an annotated and illustrated catalogue ofshark species known to date. FAO Fisheries Synopsis 125 (4), 1–655. Garrick, J. A. F. & Springer, S. (1964). Isistius plutodus, a new squaloid shark from the GulfofMexico. Copeia 1964, 678–682. Golovan, G. A. & Pakhorukov, N. P. (1986). New records ofrare species ofcartilaginous fishes. Journal of 26, 117–120. McGrouther, M. A. (2001). First record ofthe large-tooth cookie-cutter Shark, Isistius plutodus from Australian waters. Memoirs of the Queensland Museum 46, 442. Mun˜ oz-Chapuli, R., Rey Salgado, J. C. & de la Serna, J. M. (1988). Biogeography of Isistius brasiliensis in the north-eastern Atlantic, inferred from crater wounds on (Xiphias gladius). Journal of the Marine Biological Association of the United Kingdom 68, 315–321. Parin, N. V. (1975). First Pacific Ocean record of the dalatiid shark Isistius plutodus Garrick and Springer collected near Okinawa, Japan. UO, Japanese Society of Ichthyology 25, 1–3. Sadowsky, V., Arfelli, C. A. & Amorim, A. F. (1988). Primeiro registro de occurrencia de Isistius plutodus () no hemisferio sul. Suplemento de Ciencias e Cultura, Cientistas do Brasil SBPC 40, 919. Shirai, S. (1992). Squalean Phylogeny: a New Framework of ‘‘Squaloid’’ Sharks and Related Taxa. Sapporo: Hokkaido University Press.

# 2004 The Fisheries Society ofthe British Isles, Journal of Fish Biology 2004, 64, 1430–1434