大分県で養殖されていたブリ属魚類から得られたウオジラミ 属カイアシ類 2 種

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1 大分県で養殖されていたブリ属魚類から得られたウオジラミ 属カイアシ類 2 種 誌名 生物圏科学 ISSN 著者 巻 / 号 長澤, 和也 福田, 穣 50 巻 掲載ページ p 発行年月 2011 年 12 月 農林水産省農林水産技術会議事務局筑波産学連携支援センター Tsukuba Business-Academia Cooperation Support Center, Agriculture, Forestry and Fisheries Research Council Secretariat

2 ~t ~} ml I':; ': Biosphere Sci. 50 : (20 11) Two Species of Caligus (Copepoda: Caligidae) from Amberjacks (Seriola spp.) Cultured in Oita Prefecture, Kyushu, Western Japan Kazuya NAGASAWA 1 ) and Yutaka FUKUDA 2 ) I) Graduate School of Biosphere Science, Hiroshima University, Kagamiyama, Higashi-Hiroshima, Hiroshima Japan 2 ) Fisheries Research Division. Gita Prefectural Agriculture, Forestry and Fisheries Research Centel; Tsuiura, Kamiura. Saiki, Gita Japan Abstract Two species of copepods of the caligid genus Ca/iglls were found parasitic on amberjacks cultured in the Bungo Channel off the coast of Oita Prefecture, Kyushu, western Japan. They are Ca/iglls spinoslis Yamaguti, 1939 from the gills of yellowtail ambeljack (Serio{a {alandi), and Caliglls lalande! Barnard, 1948 from the body surface of Japanese ambeljaek (Serio{a CjuinCjlleradiata). This is the firs t confirmed record of C. spinoslis from 5 lalandi in Japan. Key words: aquaculture, Caliglls fafandei, Caligus spinosus, Copepoda, fish parasite, Serio{a lafandi, Serio/a CjllinCjueradiata INTRODUCTION Three species of ambeljacks (Seriofa spp., Pereiformes: Carangidae) are cultured in coastal waters of Japan: Japanese amberjaeks (5 quinqlleradiata Temminck and Schlegel), greater ambeljack (5. dllmerili Risso), and yellowtail ambeljack (5 [a/andi Valenciennes). Sincc only several works have been conducted on the parasitic copepods of 5 qllinqlleradiata farmed in Japan (e.g., Fujita et al., 1968 ; Izawa, 1969; Ho et af., 200 I; Cruz-Lacierda et al., 20 II), our knowledge on such parasites of ambeljacks is very limited. This note reports on two species of Caliglls found on ambcljacks cultured in Oita Prefccture, Kyushu, western Japan. MATERIALS AND METHODS A single 5 lalandi (5,200g body weight) was collected on 6 March 2009 from a floating cage off Tsuiura (33 2'4 TN, ' 10"E) in Kamiura, Saiki, Oita Prefecture. Also, 10 age-o 5 Cjllinqlleradiata [ (mean 16.6) cm fork length] were sampled on 13 July 2009 from a floating cage in Inokushi Cove (32 46'25"N, '52"E), Kamae, Saeki. Both sampling sites are located in the Bungo Channel. The fishes were brought to the laboratory, where copepods were removed from them and fixed in 70% ethanol. Later, the copepods were soaked in lactophenol and examined using the wooden slide procedure of Humes and Gooding (1964). Voucher specimens are deposited in the crustacean collection at the National Museum of Nature and Science, Tokyo (NSMT-Cr for C. spinoslis; NSMT-Cr for C. lalanelei). The scientific and common names of fishes follow Froese and Pauly (2011). Accepted on september 9, 20 II

3 50 Kazuya NAGASAWA and Yutaka FUKUDA RESULTS AND DISCUSSION Twenty-four (18 adult female and 6 adult male) specimens of Caliglls spinosus Yamaguti, 1939 (Fig. I) were found on the gills of a single S. lata/ldi cultured off Tsuiura in Kamiura, Saiki. The morphology of the specimens agrees to the description of the species given by Yamaguti (1939), Yamaguti and Yamasu (1960) and Choe and Kim (20 I 0). Shiino (1960) reported "Caligus spinosus" from S. lalandi (recorded as Serio/a aureoviffala Temminck and Schlegel) and an unidentified fish from Japan, but his caligid specimens are currently regarded by Choe and Kim (2010) as Caligus aesopus Wilson, While C. spinosus is known to infect both S. quinqueradiata and S. lalandi in Korean waters (Choe and Kim, 2010), it was reported only from S. quinqueradiata in Japan (Yamaguti, 1939; Yamaguti and Yamasu, 1960; Fujita et al., 1968;!zawa, 1969; Ho et ai., 2001; Nagasawa el al., 2010; Cruz-Lacierda el at., 2011). Fukuda (1999: 56) stated C. spinosus parasitized S. lalandei farmed in Oita Prefecture, but he did not provide any morphological characters of the cajigids co llected. The present collection of C. spinosus represents the first confirmed record of this parasite from S. lalandi in Japan. Fig. I. Female (A) and male (8) specimens of Caliglls SpillOSliS Yamaguti, 1939 from the gills of yellowtail amberjack (Serio/a /a/andi) cultured off Tsuiura in Kamiura, Saiki, Oita Prefecture. Alcohol-preserved specimens. Dorsal view. Scale bar: 2 mm.

4 Caligid copepods parasitic on farmed amberjacks 5 1 Twenty-seven (19 adult female and 8 adult male) specimens of Caligus lalal1dei Barnard, 1948 (Fig. 2) were taken from the body surface of eight of 10 S. quil1queradiata cultured in Inokushi Cove, Kamae. No data were taken on the number of copepods per fish. The specimens coitespond to the recent redescription of C. lalandei given by Ho et af. (200 I). The fish examined were transported in June 2009 from nearby Nyudu Cove, where they had been temporarily kept in a floating cage after caught as juveniles at sea between April and May of the same year. Previously, Fukuda (2008) also found C. lalandei on S. quil1queradiata farmed in Oita Prefecture, where this copepod species is known to parasitize fanned S. lalal1di as well (Ho et al., 2001). In Japan, C. lalal1dei has so far been reported only from coastal waters of Kyushu. Ho et af. (2001) reported that juvenile S. quil1queradiata caught in the western North Pacific off Kyushu, Shikoku and central Honshu, Japan, were infected with C. spil10sus and C. lalal1dei. Because wild-caught juvenile S. quil1queradiata are uscd as sccds for aquaculture conducted in coastal seas of Japan, both caligid specics are considered to be introduccd into farming sites with the juveniles. Moreover, once these parasites arrive at the farming sites, they appcar to easily establish there by utilizing two species of ambeljacks (s. quinqueradiata and S. lalandi) reared at high densities in seacages. Mortalities caused by C. spil10slis are known for farmed S. qllinqlleradiata (Fuj ita et al., 1968), but there has been no report about C. lalal1dei as a pathogen of farmed ambeljacks. Fig. 2. Female (A) and male (B) specimens of Caliglls /a/andei Barnard, 1948 from the body surface of Japanese amberjack (Serio/a qllinqueradiafa) cultured in Inokushi Cove, Kamae, Saiki, Oita Prefecture. Alcohol-preserved specimens. Dorsal view. Scale bar: 2 mm.

5 52 Kazuya NAGASAWA and Yutaka FUKUDA Yamaguti (1936) described Caliglls seriolae based on a single female specimen from the gills of S. quinqueradiata caught in the Seto Inland Sea, Japan. This caligid species has not been found from wild or farmed S. qllinqueradiata since its original description. REFERENCES Choe, M.-K., Kim, I.-H., Redescriptions of two morphologically confusing sea lice Caligus aesopus Wilson, 1921 and C. spinosus Yamaguti, 1939 (Copepoda: Siphonostomatoida: Caligidae) parasitic on ambetjacks (Serioia spp.) from Korea. Zootaxa, 2483: Cruz-Lacierda, E. R., Yamamoto, A., Nagasawa, K., Seasonal occurrence of Caligus spinosus and Parabrachiella seriolae (Copepoda) parasitic on cage-cultured yellowtail (Seriola quinqueradiata) at a fish farm in western Japan. Bulletin olthe European Association offish Pathologists, 30: Froese, R., Pauly, D. eds., FishBase. World Wide Web electronic publication. ( ). Fujita, S., Yoda, M., Ugajin, I., Control of an ectoparasitic copepod, Caiigus Spill0SUS Yamaguti, on the cultured adult yellowtail. Fish Pathology, 2: [In Japanese.] Fukuda, Y, Diseases of marine fishes and shellfishes cultured in Oita Prefecture diagnosed from 1980 to Bulletill oloita institute olmarine and Fisheries Science, 2: [In Japanese.] Fukuda, Y, Diagnosis and control of the diseases of cultured Japanese ambetjack. Part 3. External features of diseased fish, and observations of parasites. Yoshoku, 45(10): [In Japanese.] Ho, J.-S., Nagasawa, K., Kim, I.-H., Ogawa, K., Occurrence of Caligus laiandei Barnard, 1948 (Copepoda, Siphonostomatoida) on ambetjacks (Seriola spp.) in the western North Pacific. Zoological Sciellce, 18: Humes, A. G., Gooding, R. U., A method for studying the external anatomy of copepods. Crustacean a, 6: Izawa, K., Life history of Caligus spinosus Yamaguti, 1939 obtained from cultured yellow tail, Serioia quillqueradiata T. & S. (Crustacea: Caligoida). Report of the Faculty olfisheries, Prelectural University olmie, 6: Nagasawa, K., Uyeno, D., Tang, D., A checklist of copepods of the genus Caligus (Siphonostomatoida, Caligidae) from fishes in Japanese waters ( I 0). Bulletill o{the Biogeographical Society oljapall, 65: [In Japanese with English abstract.] Shiino, S. M., Copepods parasitic on the fishes collected on the coast of Province Shima, Japan. Report olthe Faculty ol Fisheries, PreFectural University olmie, 3: Yamaguti, S., Parasitic copepods from fishes of Japan. Part 2. Caligoida, I. Published by the author, 22 pp., 12 pis. Yamaguti, S., Parasitic copepods from fishes of Japan. Part 5. Caligoidea, III. Voiull1en Jubilare pro Prof.' Sadao Yoshida, 2: , 20 pis. Yamaguti, S., Yamasu, T., New parasitic copepods from Japanese waters. Publications ol the Seto Marine Biological Laboratory, 8: , 3 pis.

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