Abstract
A new species of chimaerid belonging to the genus Hydrolagus Gill, 1862 is described from two specimens collected from the Galapagos Islands. This species was taken from depths ranging from 600 – 900 m. Hydrolagus alphus sp. nov. is distinguished from other members of the genus by having proportionately large eyes, dark brown coloration with a noticeable white spot on lateral side, paired fins with a bluish hue and white distal margins, and second dorsal fin with dark anterior and posterior sections separated by a middle portion indented and completely white. This new species is compared to Hydrolagus macrophthalmus, the most similar congener and Hydrolagus mccoskerii the only other known species within this genus to occur in the eastern South Pacific.References
Barnett, L.A.K., Didier, D.A., Long, D.J. & Ebert, D.A. (2006) Hydrolagus mccoskeri sp.nov., a new species of chimaeroid fish from the Galapagos Islands (Holocephali: Chimaeriformes: Chimaeridae). Zootaxa, 1328, 27–38.
Bigelow, H.B. & Schroeder, W.C. (1953) Chimaeroids. In: Tee-van, J., Breder, C.M., Parr, A.E., Schroeder, W.C. and Schultz, L.P. (Eds.), Fishes of the Western North Atlantic. Part 2. Sawfishes, Guitarfishes, Shates and Rays, Chimaeroids. Yale University. Memoir Sears Foundation for Marine Research, New Haven, 1 (2), 515–562.
Chirichigno F.N. (1968) Nuevos Registros para la Ictiofauna Marina del Peru. Instituto del Mar del Peru Boletun, vol. I, num 8, 380–503.
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.
de Buen, F. (1959) Notas preliminaries sobre la fauna marina preabyssal de Chile, con descripcion de una familia de rayas, dos generos y siete especies nuevos. Boletin Del Museo Nacional De Historia Natural, 27 (3), 171–201.
Didier, D.A. (1995) Phylogenetic Systematics of Extant Chimaeroid Fishes (Holocephali, Chimaeroidei). American Museum Novitates, 3119, 1–86.
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, 115–135.
Didier, D.A. & Nakaya, K. (1999) Rediscription of Rhinochimaera pacifica (Mitsukuri) and first record of R. africana Compagno, Stehmann & Ebert from Japan (Chimaeriformes: Rhinochimaer idae). Ichthyological Research, 46, 139–152.
Didier, D.A. & Seret, B. (2002) Chimaeroid fishes of New Calendonia with description of a new species of Hydrolagus (Chondrichthyes, Holochephali). Cybium, 26 (3), 225–233.
Grove, Jack S. & Lavenberg, Robert J. (1997) The fishes of the Galapagos Islands. Stanford University Press; Stanford, California, 1–863.
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 resrouce collections in herpetology and ichthyology. Copeia, 1985 (3), 802–832.
McCosker, J.E. (1997) A half mile down: figments of fancy off the Galapagos Islands. Pacific Discovery, 50, 42–45.
McCosker, J.E., Merlen, G., Long, D.J., Gilmore, R.G. & Villon, C. (1997) Deepslope fishes collected during the 1995 eruption of Isla Fernandina, Galapagos. Noticias de Galapagos, 58, 22–26.
Soto, Jules M.R. & Vooren, Carolus, M. (2004) Hydrolagus matallanasi sp. nov. (Holocephali, Chimaeridae) a new species of rabbitfish from southern Brazil. Zootaxa, 687, 1–10.