—227—
INTRODUCTION
Recently a single juvenile fish was collected at 17 m depth of Munseom (Isl.), Jeju Island, Korea by the junior author during a survey of invertebrates using SCUBA gear. The specimen was readily identified as a member of the family Apogonidae due to having two well-sepa- rated dorsal fins, forked caudal fin, and relatively large head and eyes, although it was not an adult specimen. It was finally identified as Apogon semiornatus Peters, 1876 that widely distributes in the Indo-West Pacific owing to its distinctive reddish body color with two black- ish oblique bands, representing a new Korean record.
As mentioned by Kim et al. (2009), 11 apogonid species have been recognized from Jeju Island to date as follows:
Apogon carinatus Cuvier, A. coccineus Rüppell, A. cya- nosoma Bleeker, A. doederleini Jordan and Snyder, A.
endekataenia Bleeker, A. kiensis Jordan and Snyder, A.
lineatus Temminck and Schlegel, A. notatus (Houttuyn), A. semilineatus Temminck and Schlegel, Gymnapogon japonicus Regan, Rhabdamia gracilis (Bleeker). In the present study, we describe the juvenile characteristics of Apogon semiornatus based on a single specimen collect- ed from Jeju Island as the first record of the species from Korea as well as the twelfth apogonid species from Jeju Island. Counts and measurements follow of those of Randall (2001), and voucher specimen is deposited in the National Institute of Biological Resources (NIBR-P), Korea.
Apogon semiornatus Peters, 1876 (New Korean name:
Geom-eun-du-jul-bulg-eun-dong-gal-dom) (Fig. 1; Table 1)
Apogon semiornatus Peters, 1876: 436 (type locality:
Sulade Island, Jolo, Philippines); Ida and Moyer, 1974:
113 (Miyake, Japan).
Material examined. NIBR-P15357, 20.7 mm in stan- dard length (SL), juvenile, 22 March 2011, Munseom (Isl.), Seogwipo-si, Jeju-do, Korea, 17 m depth, water temperature 14�C, collected by Tae Seo Park, SCUBA Diving with a hand net.
Description. Dorsal fin rays VI-I, 9; anal fin rays II, 8; pectoral fin rays 12; pelvic fin rays I, 5; principal cau- dal rays 15; lateral line scales 23 (not included four scales posterior to caudal base); circumpeduncular scales 15;
gill rakers 4++13==17 (2++8 only developed rakers); ver- tebrae 24.
Proportions are presented as % SL: body depth 31.4;
head length 38.6; snout length 7.7; upper jaw length 21.3; orbit diameter 13.0; interorbital width 9.7; snout to origin of first dorsal fin 44.4; snout to origin of second dorsal fin 58.5; snout to origin of pectoral fin 42.5; snout to origin of pelvic fin 40.6; snout to origin of anal fin 63.3; caudal peduncle depth 11.6; caudal peduncle length;
27.1; base of first dorsal fin 12.6; length of first dorsal spine 3.4; length of second dorsal spine 13.5; length of third dorsal spine 13.5; base of second dorsal fin 13.5;
length of first spine of second dorsal fin 9.2; length of first soft ray of second dorsal fin 22.2; pectoral fin length 23.2; pelvic fin length 19.8; length of pelvic spine 13.5;
First Occurrence of a Juvenile Halfband Cardinalfish,
Apogon semiornatus (Apogonidae: Perciformes) from Jeju Island, Korea
By Byung-Jik Kim* and Tae Seo Park
National Institute of Biological Resources, Incheon 404-708, Korea
ABSTRACT Based on a single juvenile specimen (20.7 mm SL) collected from Jeju Island, Apogon semiornatus was described as a new Korean record. The species is characterized by having VI-I, 9 dorsal fin rays, 12 pectoral fin rays; II, 8 anal fin rays and two blackish oblique bands on yellowish red body. A new Korean name, “Geom-eun-du-jul-bulg-eun-dong-gal-dom”, is proposed.
Key words : New record, juvenile, Apogon semiornatus, Jeju Island, description
*Corresponding author: Byung-Jik Kim Tel: 82-32-590-7360, Fax: 82-32-590-3250, E-mail: [email protected]
KOREAN JOURNAL OF ICHTHYOLOGY, Vol. 24, No. 3, 227-229, September 2012 ISSN: 1225-8598
Received: July 25, 2012 Revised: September 3, 2012 Accepted: September 21, 2012
http://www.fishkorea.or.kr
base of anal fin 12.1; length of first anal spine 1.0; length of second anal spine 30.4; caudal fin length 30.4.
Body oblong and compressed, covered with large cte- noid scales. Caudal peduncle shallow and elongate. Head large and compressed. Mouth slightly inferior, oblique, and large; maxilla reaching a vertical at posterior edge of orbit, its margin truncate with round corners; a band of villiform teeth on both jaws in 5~6 irregular rows; a narrow band of villiform teeth on vomer and palatines in two irregular rows. Opercular spine at level of center of eye, flat and acute; posterior margin of preopercle with fourteen serrae. Scales finely ctenoid on entirely body including cheek and opercle; seven predorsal scales in median line; two median scales between dorsal fins.
Origin of dorsal fin over third lateral line scale, spines on dorsal stout, especially the second. Origin of anal fin below third ray of second dorsal fin, first anal spine minute, first anal soft ray longest. Caudal fin slightly forked with broad rounded lobes. Pectoral fin relatively small and pointed, fourth ray longest. Origin of pelvic fin slightly anterior to base of pectoral fin.
Color when fresh. Head and body translucent yellow- ish red with a mid-lateral blackish stripe commencing below second dorsal and broadening posteriorly to end of caudal fin. Nape blackish. Dark yellowish red oblique stripe from tip of snout to base of pectoral fin. Bases of dorsal, anal, and caudal fins dark yellowish red. Perito- neum black.
Distribution. Known from the Indo-Pacific: Red Sea
and Gulf of Oman, to KwaZulu-Natal, South Africa, Chagos, Mauritius, to southern Japan and Korea (present study) to the Great Barrier Reef and New Caledonia (see Gon and Randall, 2003 for more information).
Remarks. The present juvenile specimen of Apogon, being collected from the southern coastal waters of Jeju Island, shows two distinctive morphological characteri- stics to confirm the identification to species level, i.e., a reddish body color and two oblique bars on body. We, therefore, easily identified the specimen as a juvenile of Apogon semiornatus Peters. Recently several unrecorded juvenile fishes have also been newly reported from Korea, especially at the coastal waters of Jeju Island (Kim et al., 2006, 2007). It is not confirmed yet whether they were settled in the Korean waters or not since then. It is also not determined yet whether the occurrence of A. semior- natus in the coastal waters of Jeju Island was resulted from as part of an abortive migration influenced by the Tsushima Current or from its ecological features as a secretive species (sensu Randall, 2001). Further investi- gations to solve the question are needed in the near future.
Some distinguishable characters between Apogon semi- ornatus and its most similar species A. lativittatus were given by Randall (2001) as follows (Table 1): the former differs from the latter by the modal count of pectoral fin rays (12 vs. 13 for A. lativittatus), the smaller number of circumpeduncular scales (15~17 vs. 19~23) and the smaller number of small pored scales in the lateral line posterior to the caudal fin base (4 vs. 5). The Korean name, “Geom-eun-du-jul-bulg-eun-dong-gal-dom”, is proposed for the species referring to its having two black- ish stripes on reddish body.
ACKNOWLEDGMENTS
We thank to Mr. Soon-Tae Youn and Mr. Hyun-Soo Kim for their field assistance for collecting the specimen,
228 Byung-Jik Kim and Tae Seo Park
Fig. 1. Fresh juvenile of Apogon semiornatus, NIBR-P15357, 20.7 mm SL Munseom (Isl.), Jeju Island, Korea, photo by B.J. Kim.
Table 1. Comparison of diagnostics between Apogon semiornatus and A. lativittatus
A. semiornatus A. lativittatus (Present study) (Randall, 2001)
Modal counts of pectoral fin rays 12 13
Circumpeduncular scales 15 19~23
Pored scales after caudal fin base 4 5
and also thank to Mr. Hyun-Geun Cho for his taking a radiograph of the fish.
REFERENCES
Gon, O. and J.E. Randall. 2003. A review of the cardinalfishes (Perciformes: Apogonidae) of the Red Sea. Smithania Bulletin 1, 48pp.
Ida, H. and J.T. Moyer. 1974. Apogonid fishes of Miyake- jima and Ishigki-jima, Japan, with description of a new species. Japanese Journal of Ichthyology, 21:
113-128.
Kim, B.J., I.S. Kim, K. Nakaya, M. Yabe, Y. Choi and H.
Imamura. 2009. Checklist of fishes from Jeju Island, Korea. Bulletin of Fisheries Sciences, Hokkaido Uni- versity, 59: 7-36.
Kim, B.J., K. Nakaya and H. Endo. 2007. Three juvenile snappers of the genus Lutjanus (Perciformes: Lutjani- dae) collected from Jeju Island, Korea. Fisheries Sci- ence and Technology, 10: 68-73.
Kim, B.J., Y.D. Lee and S.Y. Kim. 2006. Occurrence of ju- venile Orbicular batfish, Platax orbicularis (Ephippi- dae), from Jeju Island, Korea. Korean Journal of Ichthyology, 18: 55-58.
Peters, W. (C.H.). 1876. Übersicht der von Hrn. Prof. Dr. K.
Möbius in Mauritius und bei den Seychellen gesam- melten Fische. Monatsberichte der Königlichen Preuss Akademie der Wissenschaften zu Berlin, 1876: 435- 447.
Randall, J.E. 2001. Four new cardinalfishes (Perciformes:
Apogonidae) from the Marquesas Islands. Pacific Science, 55: 47-64.
Occurrence of Apogon semiornatus from Korea 229
제주도 연안에서
처음 출현한 동갈돔과 유어 Apogon semiornatus
김병직∙박태서
국립생물자원관 동물자원과
요 약 :제주도 연안에서 처음 채집된 동갈돔과 유어 1개체 (체장 20.7 mm)를 근거로 Apogon semiornatus를 한국미기록종으로서 기재하였다. 본 종은 등지느러미 기조수 VI-I, 9, 가슴지느러미 기조수 12; 뒷지느러미 기조 수 II, 8, 채색은 황적색 바탕으로 체측에 2개의 흑색 사행대가 있는 점에서 국내의 동속 유사종과 쉽게 구별되 며, 국명은 ‘검은두줄붉은동갈돔’으로 명명하였다.
찾아보기 낱말 :동갈돔과, 유어, Apogon semiornatus, 제주도, 기재
