Japanese Journal of Ichthyology 魚類 学雑 誌 Vol.19,No.2September20,1972 19巻2号1972年9月20日

Gobiodon okinawae,a New Coral-Goby from, the Ryukyu Islands,Japan

Yukio Sawada,Ryoichi Arai,and Tokiharu Abe (Received March18,1972)

Abstract Seventeen specimens of a new species of Gobiodon were collected along with eight specimens of G.quinquestrigatus and three specimens of G.citrinus from the Yaeyama Islands, southernmost islands of Okinawa Prefecture.The new fish is similar to,but different from G. atrangulatus and Pseudogobiodon macrochir,and is named here G.okinawae.Several character- istics of the new species are described,with special reference to the differences from G.quinque- strigatus,G.citrinus,G.atrangulatus,and Pseudogobiodon macrochir.

Several species of the genus Gobiodon macrochir in the following points:(1) two Bleeker,1856,have been reported from the canines*on each side of lower jaw(Fig.2), Indo-Pacific Ocean(McCulloch and Ogilby, and(2)first dorsal fin obtuse(Fig.3).G. 1919;Koumans,1953;Smith,1959). okinawae sp.nov.also differs from the other In Japan,three species of coral-gobies have two species in(1)pectoral fin rays,16-17,(2) been recorded from the Nan-sei Islands two pairs of canine teeth of lower jaw,(3) including the Ryukyu Islands,southern Japan muscle pattern of ventral fin base characteris- (Tomiyama,1936;Aoyagi,1943;Matsubara, tic(Fig.4),and(4)no black spot on operculum. 1955).These Japanese coral-gobies are identi- Material.Holotype:NSMT-P17438(De- fied at present with G.rivulatus(Ruppell,1828), partment of Zoology,Natural History Institute, G.quinquestrigatus(Cuvier et Valenciennes, National Science Museum),22.5mm in stand- 1837),and G.micropus Gunther(1861), ard length,26.6mm in total length;collected although the classification of these fishes should at Kayama Island,Yaeyama Islands,Okinawa, be re-examined by further investigation. Japan,on August11,1970. Among the collections made in1970-1971 Paratopotypes:Three specimens,NSMT-P from the Yaeyama Islands,17specimens 17437,17439,17440,in the same Department which seem to represent a new species were described above,17.8-22.0mm in standard found along with three specimens of G. length. citrinus(Ruppell,1835)and eight specimens Paratypes:Thirteen specimens,NSMT-P of G.quinquestrigatus. 17441-17453,13.1-29.9mm in standard length; In the following lines,the new fish will be collected at Kabira,Ishigaki Island,Yaeyama described,with special reference to the differ- Islands,Okinawa,Japan,on August5,1971. ences from G.citrinus,G.quinquestrigatus,and Description.In the succeeding paragraphs, G.atrangulatus Garman(1903). body proportions and counts for the holotype are followed by those of paratypes(in paren- Gobiodon okinawae sp.nov. theses). [Kiiro-sango-haze:new Japanese name] D1.VI(VI);D2.I,10(I,10-11);A.I,9(I,9- Diagnosis.As shown in Table1,the pres- 10);P.16(16-17);V.I,5(I,5);branched ent new species resembles Pseudogobiodon *Dr .Boeseman kindly re-examined the holotype of macrochir Bleeker(1875),G.citrinus and G. P.macrochir on our request, and confirmed absence atrangulatus.It,however,differs from P. of canines in its lower jaw.

•\ 57•\— 魚 類学雑 誌Japan.J.Ichthyol.19(2) September20,1972

Fig.1.Gobiodon okinawae sp.nov.A paratype,26.0mm in standard length ,from Ishigaki Island.

Table1.Comparison of several characteristics of4species of the genus Gobiodon .

•\ 58•\ Sawada,Arai,and Abe:New Goby of the Genus Gobiodon

A C

B D

Fig.2.Dentaries of Gobiodon.A and B,G.okinawae(A,S.L.24.7mm;B,S.L.16.5 mm);C,G.quin- questrigatus(S.L.25.0mm);D,G.citrinus(S.L.28.0mm).Above,dorsal view;below,lateral view. caudal,13(13).Vertebrae with hypural plate to orbit(Fig.6C).Snout very obtuse,shorter counted as one,10+16(10+16);branchio- than orbit.Nostril tubular,the posterior stegals,(5). placed just before eye.Mouth a little oblique, Measurements expressed in hundredths of jaws subequal.Maxillary extending to below standard length:body depth33.3(28.7-36.4), middle of orbit(Fig.6D).In lower jaw body width13.6(9.7-14.2),head length28.1 teeth in rows,pointed,small,with two pairs (26.3-32.4),snout length5.1(5.1-6.3),orbit of canines behind symphysis (Fig.2A).In diameter8.4 (6.8-10.1),maxillary length7.4 specimens smaller than17.8mm in standard (7.4-10.2),pectoral length24.9,caudal length length,canines none or difficult to see(Fig. 22.7,and the least depth of caudal peduncle 2B).Depth of caudal peduncle very narrow, 14.4(12.3-16.4). 7(6.1-8.1)in standard length(Fig.6E). Body strongly compressed,height3.4(3.2— Gill-opening as wide as base of pectoral, 4.2)in total length(Fig.6A).Head- com- extending from the uppermost part of pectoral pressed,a little more than4in total length,a fin base to the lowest second ray of pectoral little higher than long (Fig.6B).Its upper (Fig.5A). First dorsal commencing above base of profile convex,chin prominent.Orbit3.4 (3.1-4.2)in head, interorbital width subequal pectoral,not or a little lower than second

•\ 59•\— 魚 類 学 雑 誌Japan.J.Ichthyol.19(2) September20,1972

from half to three-fourths of their distance from vent. As shown in Fig.4,muscle pat- A tern of ventral fin base intermediate type between those of G.citrinus and G. atrangu- latus.Caudal rounded,a little shorter than head. Head and body naked.Whole surface of B head and body covered with thick granular mucous cells which obscure the characters beneath it.Twenty-one vertical series of minute pores which might represent lateral line ar- ranged along median line from above gill- opening to caudal fin base.Each of plate- C like units of lateral line with3or4micro- pores(Fig.1). Canal pores and pit organs on head:six large tubular pores extending around pre- opercular border to behind eye,two others on D interorbital space and a pair between posterior nostrils.Microscopic pit organs present on Fig.3.Dorsal fins of Gobiodon.A,G.okinawae; B,G.atrangulatus;C,G.citrinus;D,G. lower preopercular border,beneath lower lip, quinquestrigatus. above upper lip,between nostrils,behind eye, and upper opercular margin(Fig.1). dorsal;4th spine the highest in first dorsal. Color in life:uniformly yellow,operculum The first spine of second dorsal separated with no spots and no stripes,no edged lines from the sixth spine by a wide interspace,and along bases of dorsal and anal fins. united by membrane(Fig.3A).Length of Distribution.Kayama and Ishigaki Islands, 10th soft ray of second dorsal subequal to the Yaeyama Islands,Okinawa Prefecture, that of spine of second dorsal.Anal com- southern Japan. mencing behind anterior origin of second Etymology.The species name,okinawae, dorsal.Urogenital papilla large.Pectoral was coined to refer the locality of the new rounded,a little shorter than head.Ventral species. small,2 in head; cup-shaped,with a broad Notes.Materials examined of the other basal membrane,the median rays reaching species of Gobiodon are as follows,

A B C D Fig.4.Ventral fins of Gobiodon.A,G.okinawae;B,G.atrangulatus;C,G.citrinus;D,G.quinquestrigatus.

•\ 60•\ Sawada,Arai,and Abe:New Goby of the Genus Gobiodon

A B Fig.5.Gill-opening(bold line)of G.okinawae (A),and G.citrinus(B).

G.citrinus:Two specimens,NSMT-P 17473,17474,28.0-33.7 mm in standard length,Kayama Island,on August,1971. One specimen,NSMT-P 17475,18.3 mm in standard length,Kabira,Ishigaki Island, on November,1971. G.quinquestrigatus:Eleven specimens, NSMT-P 17454-17464,24.6-33.9 mm in standard length,Yadon,Amami-oshima,on August 9-15,1971.Four specimens, NSMT-P 17469-17472,23.5-29.9 mm in standard length,Kayama Island,on August, 1971. G.atrangulatus:One specimen,NSMT-P 10813,23.0 mm in standard length,Ogasa- wara Islands,on July 5,1969.

Acknowledgments

The authors wish to express their gratitudes to Dr.M.Boeseman of Leiden Museum for his kindness in examining and sending a photocopy of theunpublished drawing by Bleeker of the holotype of Pseudogobiodon

Fig.6.Relative size of body depth(A),head

length(B),orbit diameter(C),maxillary length

(D),and the least depth of caudal peduncle (E)of four species of Gobiodon:G.okinawae

(•œ),G.quinquestrigatus(•›),G.atrangulatus (•£),and G.citrinus(•¢).Ordinate,propor- tional length in percent of standard length; abscissa,standard length in mm.

―61― 魚類学雑誌 Japan.J.Ichthyol.19(2) September 20,1972 macrochir Bleeker.They are also indebted to Frankfurt am Main, 47 pp.,35 pls. Prof.Yoshiro Hashimoto of Laboratory of Ruppell, E. 1835. Fische des rothen Meers. Neue Wirbeltiere zu der Fauna von Abyssinien gehorig. Marine Biochemistry,Faculty of Agriculture, Frankfurt am Main, ii+118 pp.,33 pls. Tokyo University,Dr.Hitoshi Ida,University Smith, J. L. B. 1959. Gobioid fishes of the families Museum,Tokyo University and Dr.Minoru Gobiidae, Periophthalmidae, Trypauchenidae, Tae- Imajima,Department of Zoology,National nioididae and Kraemeriidae of the Western Indian Science Museum,for offering materials. Ocean. Rhodes Univ., Dept. Ichthyol., Ichthyol Bull., (13): 185-225, 42 figs., pls. 9-13. . Tomiyama, I. 1936. Gobiidae of Japan. Japan. J. Literature cited Zool., 7: 37-112, 44 figs.

Aoyagi, H. 1943. Coral fishes. Maruzen Co., Tokyo, (College of Agriculture and Veterinary Medicine, xii+224 pp., 54 figs., 37 pls. Nihon University,Tokyo;Department of Zoology, Bleeker, P.1856. Bijdrage tot de kennis der ichthyol- Natural History Institute,National Science Museum, ogische fauna van het eiland Boeroe. Descriptiones Tokyo;and Tokai Regional Fisheries Research Labora- specierum diagnosticae. Nat. Tijdschr. Ned. Ind., tory,Tokyo,Japan) 11: 394-414. Bleeker, P.1875. Gobioideorum species insulindicae novae. Arch. Need. Sc. Nat., 10: 113-134. 八 重 山 群 島 よ り 採 集 さ れ た コ バ ン ハ ゼ 属 の 一 新 種, Cuvier, G. and A. Valenciennes. 1837. Histoire に つ い て Gobiodon okinawae naturelle des poissons. XII. Paris, xxiv+507 pp. Garman, H. 1903. Some fishes from Australia. 澤 田 幸 雄 ・新 井 良 一 ・阿 部 宗 明 Bull. Mus. Comp. Zool., Harvard Coll., 39: 229- コ バ ン ハ ゼ 類 は 南 海 の サ ン ゴ 礁 に 普 通 に 見 ら れ る 側 偏 241, 5 pls. し た 楕 円 形 の 小 型 の ハ ゼ で あ る が,本 類 の 分 類 は 学 者 に

Gunther, A. 1861. Catalogue of the fishes in the よ り ま ち ま ち で 必 ら ず し も 明 確 と は い え な い 。 British Museum. III. London, Brit. Mus. (Nat. こ の た び,八 重 山 諸 島 よ り採 集 し た 標 本 の な か に,3 Hist.), xxv+586 pp. Koumans, F. P.1953. The fishes of the Indo-Austra- 尾 のGobiodon citrinus,8尾 のG.quinquestrigatusと 共 lian Archipelago. X. Gobioidea. E. J. Brill, Leiden, に17尾 の 新 種 と考 え られ る コ バ ン ハ ゼ が 見 い だ さ れ xiii+423 pp., 95 figs. た 。 本 種 をG.okinawaeと し て 記 載 し,和 名 と し て キ イ Matsubara, K. 1955. Fish morphology and hierar- ロ サ ン ゴ ハ ゼ を 提 唱 す る.本 種 の 特 徴 をG.citrinus,G. chy.Part II. Ishizaki Shoten, Tokyo, v+791- 1605 pp., figs. 290-536. In Japanese. quinquestrigatus,G.atrangulatusお よ びPseudogobiodon McCulloch, A. R. and J. D. Ogilby. 1919. Some macroChirと 比 較 し て 報 告 し た 。 Australian fishes of the family Gobiidae. Rec. Austr. Mus., 12: 193-291, figs. 4-5, pls. 31-37. (東 京 都 世 田 谷 区 下 馬 日 本 大 学 農 獣 医 学 部 ・東 京 都 新 Ruppell, E. 1828. Fische des rothen Meers. Atlas 宿 区 百 人 町 国 立 科 学 博 物 館 動 物 研 究 部 ・東 京 都 中 央 zu der Reise im nordlichen Afrika. Zoologie, 区 勝 ど き 東 海 区 水 産 研 究 所)

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