Abstract
A new species of chimaeroid, Hyd rolagus mccosker i sp. nov., is described from the Galápag os Islands. This species represents the second member of the family Chimaeridae known from the eastern equatorial Pacific. It can b e distinguis hed from its congeners by a combination of the following characters: small head with short, blunt snout; preopercu lar and oral lateral line canals branching from the same node off the infraorbital canal and sharing a short common b ranch; dorsum medium brown with numerous narrow, shar ply delineated circular and elongate white blotches; ventrum white to tan with extremely fine brown mottl ing. The species is compared to Hyd rolagus n ovaezealandiae and Hyd rolagus colliei , the most similar congeners in color pattern and morphology.References
Allen, M.J. & Smith, G.B. (1988) Atlas and Zoogeography of Common Fishes in the Bering Sea and Northeastern Pacific. NOAA Technical Report NMFS 66, National Oceanographic and Atmospheric Administration, Washington, D.C., 151 pp.
Anderson, O.F., Bagley, N.W., Hurst, R.J., Francis, M.P., Clark, M.R. & McMillan, P.J. (1998) Atlas of New Zealand fish and squid distributions from research bottom trawls. NIWA Technical Report 42, National Institute of Water and Atmospheric Research, Wellington, New Zealand, 303 pp.
Chirichigno, N.F. (1968) Nuevos registros para la ictiofauna marina del Peru. Boletin Instituto del Mar del Peru, 1, 380–503.
Compagno, L.J.V. (2005) Checklist of living Chondrichthyes. In: Hamlett, W.C. (Ed.), Reproductive Biology and Phylogeny of Chondrichthyes: Sharks, Batoids and Chimaeras. Science Publishers, Inc., Enfield, NH, pp. 503–548.
Compagno, L.J.V., Stehmann, M. & Ebert, D.A. (1990) Rhinochimaera africana, a new longnose chimaera from southern Africa, with comments on the systematics and distribution of the genus Rhinochimaera Garman, 1901 (Chondrichthyes, Chimaeriformes, Rhinochimaeridae). South African Journal of Marine Science, 9, 201–222.
Cox, A. (1983) Ages of the Galápagos Islands. In: Bowman, R., Berson, M. & Leviton, A. (Eds.), Patterns of Evolution in Galápagos Organisms. American Association for the Advancement of Science, San Francisco, CA, pp. 11–23.
de Buen, F. (1959) Notas preliminares sobre la fauna marina preabismal de Chile, con descripcion de una familia de rayas, dos generos y siete especias nuevos. Boletin del Museo Nacional de Historia Natural, Santiago, Chile, 27, 171–201.
Didier, D.A. (1995) Phylogenetic systematics of extant chimaeroid fishes (Holocephali, Chimaeroidei). American Museum Novitates, 3119, 86 pp.
Didier, D.A. (1998) The leopard Chimaera, a new species of chimaeroid fish from New Zealand (Holocephali, Chimaeriformes, Chimaeridae). Ichthyological Research, 45, 281–289.
Didier, D.A. (2002) Two new species of chimaeroid fishes from the southwestern Pacific Ocean (Holocephali, Chimaeridae). Ichthyological Research, 49, 299–306.
Didier, D.A. (2004) Phylogeny and classification of extant Holocephali. In: Carrier, J.C., Musick, J.A. & Heithaus, M.R. (Eds.), Biology of Sharks and their Relatives. CRC Press, Boca Raton, FL, pp. 115–135.
Didier, D.A. & Nakaya, K. (1999) Redescription of Rhinochimaera pacifica (Mitsukuri) and first record of R. africana Compagno, Stehmann and Ebert from Japan (Chimaeriformes: Rhinochimaeridae). Ichthyological Research, 46, 139–152.
Didier, D.A. & Rosenberger, L.J. (2002) The spotted ratfish, Hydrolagus colliei: notes on its biology with a redescription of the species (Holocephali: Chimaeridae). California Fish and Game, 88 (3), 112–125.
Didier, D.A. & Séret, B. (2002) Chimaeroid fishes of New Caledonia with description of a new species of Hydrolagus (Chondrichthyes, Holocephali). Cybium, 26, 225–233.
Didier, D.A., Stahl, B.J. & Zangerl, R. (1994) Development and growth of compound tooth plates in Callorhinchus milii (Chondrichthyes, Holocephali). Journal of Morphology, 222, 73–89.
Didier, D.A. & Stehmann, M. (1996) Neoharriotta pumila, a new species of longnose chimaera from the northwestern Indian Ocean (Pisces, Holocephali, Rhinochimaeridae). Copeia, 1996 (4), 955–965.
Ekman, S. (1953) Zoogeography of the Sea. Sidgwick & Jackson, London, 477 pp.
Eschmeyer, W.N., Herald, E.S. & Hammann, H. (1983) A Field Guide to Pacific Coast Fishes of North America. Houghton Mifflin Company, Boston, 336 pp.
Grogan, E.D. & Lund, R. (2004) Biology of sharks and their relatives. In: Carrier, J.C., Musick, J.A. & Heithaus, M.R. (Eds.), Biology of Sharks and their Relatives. CRC Press, Boca Raton, FL, pp. 3–32.
Grove, J.S. & Lavenberg, R.J. (1997) The Fishes of the Galápagos Islands. Stanford University Press, Stanford, California, 863 pp.
Leviton, A.E., Gibbs Jr., R.H., Heal, E. & Dawson, C.E. (1985) Standards in herpetology and ichthyology: Part I. Standard symbolic codes for institutional resource collections in herpetology and ichthyology. Copeia, 1985 (3), 802–832.
Maisey, J.G. (1984) Chondrichthyan phylogeny: a look at the evidence. Journal of Vertebrate Paleontology, 4 (3), 359–371.
Maisey, J.G. (1986) Heads and tails: a chordate phylogeny. Cladistics, 2, 201–256.
McCosker, J.E. (1997) A half mile down: figments of fancy off the Galápagos Islands. Pacific Discovery, 50, 42–45.
McCosker, J.E. (1998) (Review of) The fishes of the Galápagos Islands by Grove, J.S. and Lavenberg, R.J., 1997. Copeia, 1998 (3), 809-812.
McCosker, J.E., Merlen, G., Long, D.J., Gilmore, R.G. & Villon, C. (1997) Deepslope fishes collected during the 1995 eruption of Isla Fernandina, Galápagos. Noticias de Galápagos, 58, 22–26.
Miller, D.J. & Lea, R.N. (1972) Guide to the coastal marine fishes of California. Fish Bulletin, 157, 249 pp.
Moura, T., Figueiredo, I., Bordalo-Machado, P., Almeida, C. & Gordo, L.S. (2005) A new deep-water chimaerid species, Hydrolagus lusitanicus n. sp., from off mainland Portugal with a proposal of a new identification key for the genus Hydrolagus (Holocephali: Chimaeridae) in the north-east Atlantic. Journal of Fish Biology, 67, 742–751.
Patterson, C. (1992) Interpretation of the toothplates of chimaeroid fishes. Zoological Journal of the Linnean Society, 106, 33–61.
Schaeffer, B. (1981) The xenacanth shark neurocranium with comments on the elasmobranch phylogeny. Bulletin of the American Museum of Natural History, 169, 3–66.