A New Species of Skate (Chondrichthyes : Rajidae), Okamejei mengae from the South China Sea

남중국해산 홍어과 (연골어강, 홍어과) 어류 신종, Okamejei mengae sp. nov.

  • Jeong, Choong-Hoon (Research Center for Coastal Environments of Yellow Sea, Inha University) ;
  • Nakabo, Tetsuji (The Kyoto University Museum, c/o Division of Applied Biosciences, Kyoto University) ;
  • Wu, Han Ling (Laboratory of Fishes, Shanghai Fisheries University)
  • Received : 2006.12.22
  • Accepted : 2007.02.05
  • Published : 2007.03.31

Abstract

A new species of the rajid genus Okamejei is described from a single specimen (295 mm TL) from off Shantou, Gwangdong in the South China Sea. The new species differs from all other congeners in the following combination of characters: snout pointed, dorsal head length 6.7 times interorbital width, tail moderately wide and long, its length 48.5% TL, interdorsal distance less than length of first dorsal fin base, postdorsal tail short as 5.8% TL, small evenly distributed dark brownish spots, without ocelli on dorsal surface of disc, pores of ampullae of Lorenzini on ventral surface distributed from snout tip to distal end of metapterygium, scapulocoracoid high, its height about 1.4 times rear corner height, trunk vertebrae 23, predorsal tail vertebrae 50 and pectoral fin radials 96.

중국 상해수산대학에 소장된 어류 표본 중에 남중국해에서 채집된 1개체의 표본(295 mm TL)을 근거로 하여 홍어속(Okamejei) 어류의 신종을 기재하였다. 홍어속 어류는 북서태평양에 6종, 인도양에 3종이 서식하여 전세계에 9종이 유효하다. 호주 해역에는 홍어속의 미기재종 1종과 근연종으로 살홍어속(Dipturus)으로 소속이 변경된 3종이 서식한다. Okamejei mengae sp. nov.는 문연골 길이가 두장의 54.3%로 주둥이가 짧고, 꼬리부가 전장의 48.5%로 길고, 미극이 3열, 신경두개의 상생체공의 전단부가 명확하게 구별되는 점 등으로 홍어속에 포함된다. 이 종은 복추골이 23개로서 적고, 등지느러미 앞까지의 미추골이 50개로 많으며, 가슴지느러미의 복사연골이 96개로 많은 특징 등으로 동일속의 9종 및 근연종 등 13종과 명확히 구별된다. 또한 뾰족하게 돌출된 주둥이, 양안간격이 6.7배로 긴 두장, 넓은 꼬리, 좁은 제1등지느러미와 제2등지느러미의 거리, 짧은 제2등지느러미 뒤의 길이, 체반 등쪽에 작고 짙은 갈색 반점이 전체적으로 분포하지만 큰 반점은 없고, 배쪽의 로렌치니 병상 기관은 가슴지느러미의 후담기연골(metapterygium)의 뒤까지 분포하며, 견갑오훼연골이 높은 특징을 가지고 있다. 신종과 전 세계 홍어속 및 근연종 등 13종과의 특징 비교표를 작성하였으며, 북서태평양에 서식하는 7종에 대한 새로운 분류 검색표를 제시하였다.

Keywords

References

  1. Chu, Y.T. and Q.W. Meng. 1979. Monograph of fishes of China. No. 2. A study of the lateral-line canals system and that of Lorenzini ampullae and tubules of elasmobranchiate fishes of China. Science and Technology Press, Shanghai, iv+132 pp., 1-71 pls. (in Chinese with English abstract)
  2. Compagno, L.J.V. 1999. Checklist of living elasmobranchs. In: Hamlett, W.C. (ed.), The Biology of Elasmobranch Fishes. Johns Hopkins Univ. Press, Baltimore and London, pp. 471-498
  3. Fricke, R. and L.A.J. Al-Hassan. 1995. Raja pita, a new species of skate from the Arabian/Persian Gulf (Elasmobranchii : Rajiformes). Stuttg. Beitr. Naturk. Ser. A (Biol.) 529 : 1-8
  4. Hubbs, C.L. and R. Ishiyama. 1968. Methods for the taxonomic study and description of skates (Rajidae). Copeia (1968) : 483-491
  5. Hulley, P.A. 1972. The origin, interrelationship and distribution of southern African Rajidae (Chondrichthyes, Batoidei). Ann. S. Afr. Mus., 60 : 1-103
  6. Ishihara, H. 1987. Revision of the Western North Pacific species of the genus Raja. Japan. J. Ichthyol., 34 : 241 -285
  7. Ishiyama, R. 1958. Studies on the rajid fishes (Rajidae) found in the waters around Japan. J. Shimonoseki Coll. Fish., 7 : 193-394
  8. Last, P. and J.D. Stevens. 1994. Sharks and Rays of Australia. CSIRO, Tasmania, pp. 299-359
  9. Last, P. and G.K. Yearsley. 2002. Zoogeography and relationships of Australasian skates (Chondrichthyes: Rajidae). J. Biogeogr., 29 : 1627-1641 https://doi.org/10.1046/j.1365-2699.2002.00793.x
  10. McEachran, J.D. and L.J.V. Compagno. 1979. A further description of Gurgesiella furvescens with comments on the interrelationships of Gurgesiellidae and Pseudorajidae (Pisces, Rajoidei). Bull. Mar. Sci., 29 : 530-553
  11. McEachran, J.D. and K.A. Dunn. 1998. Phylogenetic analysis of skates, a morphologically conservative clade of elasmobranchs (Chondrichthyes: Rajidae). Copeia (1998) : 271-290
  12. McEachran, J.D. and J.D. Fechhelm. 1982. A new species of skates from Western Indian Ocean, with comments on the status of Raja (Okamejei) (Elasmobranchii, Rajiformes). Proc. Biol. Soc. Wash., 95 : 440-455
  13. McEachran, J.D. and H. Konstantinou. 1996. Survey of the variation in alar and malar thorns in skates: phylogenetic implication (Chondrichthyes: Rajoidedi). J. Morph., 228 : 165-178 https://doi.org/10.1002/(SICI)1097-4687(199605)228:2<165::AID-JMOR5>3.0.CO;2-4
  14. McEachran, J.D. and T. Miyake. 1986. Interrelationships within a putative monophyletic group of skates (Chondrichthyes, Rajoidei, Rajini). In: Uyeno, T.R., Arai, T. Taniuchi and K. Matsuura (eds.), Indo-Pacific Fish Biology: Proc. on the Second International Conference of Indo-Pacific Fishes. Ichthyol. Soc. Japan, Tokyo, pp. 281-290
  15. McEachran, J.D. and T. Miyake. 1990a. Phylogenetic interrelationships of skates: a working hypothesis (Chondrichthyes, Rajoidei). In: Pratt, H.L., Jr., S.H. Gruber and T. Taniuchi (eds.), Elasmobranchs as Living Resources: Advances in the Biology, Ecology, Systematics, and the Status of the Fisheries. U.S. Department of Commerce, Washington, D.C., NOAA Tech. Rep. NMFS 90 : 285- 304
  16. McEachran, J.D. and T. Miyake. 1990b. Zoogeography and bathymetry of skates (Chondrichthyes, Rajoidei). In: Pratt, H.L., Jr., S.H. Gruber and T. Taniuchi (eds.), Elasmobranchs as Living Resources : Advances in the Biology, Ecology, Systematics, and the Status of the Fisheries. U.S. Department of Commerce, Washington, D.C., NOAA Tech. Rep. NMFS 90 : 305-326
  17. McEachran, J.D. and M. Stehmann. 1984. A new species of skate, Neoraja carolinensis, from off the southeastern United States (Elasmobranchii : Rajoidei). Proc. Biol. Soc. Wash., 97 : 724-735
  18. Stehmann, M. 1976. Revision der Rajoiden-Arten des nördlichen Indischen Ozean und Indopazifik (Elasmobranchii, Batoidea, Rajiformes). Beaufortia, 24 : 133-175