Abstract
Sinepecten segonzaci new genus and new species is described from a thermal vent environment in the Manus back-arc basin, North of New Guinea (south-western Pacific) at 1620–1680 m depth. Sinepecten segonzaci has close affinities with species of the genera Bathypecten and Catillopecten. It differs from the living fossil B. vulcani Schein-Fatton, 1985 from hydrothermal vents of the East Pacific Rise (13°N, 2630 m) in its ornamentation and in two main derived characters of the right valve: a prismatic shell microstructure is restricted to the juvenile stage and there is a specialized byssal notch in the new genus and species. Characters, shell ontogeny and biogeography of the three genera Bathypecten, Catillopecten and Sinepecten are compared to discuss their place in pectinid evolution.Keys words: Sinepecten segonzaci, new taxa, ontogeny, hydrothermal vents, back-arc basin, Western Pacific, Bivalvia, PectinidaeReferences
Bernard F.R. (1972) Occurrence and function of lip hypertrophy in the Anisomyaria (Mollusca, Bivalvia). Canadian Journal of Zoology, 50, 53–57.
Bernard F.R. (1978) New bivalve molluscs, Subclass Pteriomorphia, from the Northeastern Pacific. Venus, Japanese Journal of Malacology, 37, 61–75.
Chantler P.D. (1991) The structure and function of scallop adduction muscles. In: Shumway S.E. (Ed.), Scallops: Biology, Ecology and Aquaculture, Developments in aquaculture and fisheries science, 21, Elsevier, Amsterdam, 225–304.
Cox L.R. (1969a) Family Oxytomidae Ichikawa, 1958. In: Moore R.C. (Ed.), Treatise on Invertebrate paleontology, part N, Mollusca 6, Bivalvia, The Geological Society of America, Boulder, N344–N346.
Cox L.R. (1969b) Family Buchiidae Cox, 1953. In: Moore R.C. (Ed.), Treatise on Invertebrate paleontology, part N, Mollusca 6, Bivalvia, The Geological Society of America, Boulder, N374–N377.
Dautzenberg P. & Bavay A. (1912) Les lamellibranches de l’expédition du Siboga. Partie systématique. I. Pectinidés. E.J. Brill, Leide, 1–41.
Desbruyères D., Hashimoto J. & Fabri M.C. (2005) Composition and Biogeography of Hydrothermal Vent Communities in Western Pacific Back-Arc Basins. Geophysical Monographs, in press.
Dijkstra H. & Gofas S. (2004) Pectinoidea (Bivalvia: Propeamussiidae and Pectinidae) from some northeastern Atlantic seamounts. Sarsia, North Atlantic Marine Science, 89, 33–78.
Dijkstra H. & Marshall B.A. (1997) Pectinoidea (Mollusca: Bivalvia: Propeamussiidae: Pectinidae) of the Lord Howe Island, Norfolk Island and the Kermadec Islands. Molluscan Research, 18: 73–114.
Galkin S.V. (1997) Megafauna associated with hydrothermal vents in the Manus Back-Arc Basin (Bismarck Sea). Marine Geology, 142, 197–206.
Geiger D.L. & Thacker C.E. (2005) Molecular phylogeny of Vetigastropoda reveals non-monophyletic Scissurellidae, Trochoidea and Fissurelloidea. Molluscan Research, 25, 47–55.
Gould S.J. (1977) Ontogeny and phylogeny, Harvard University Press, Cambridge, 1–501.
Hashimoto J., Ohta S., Fiala-Médioni A., Auzende J.M., Kojima S., Segonzac M., Fujiwara Y., Hunt J.C., Gena K., Miura T., Kikushi T., Yamagushi T., Toda T., Chiba H., Tsuchida S., Ishibashi J., Henry K., Zbiden M., Pruski A., Inoue A., Kobayashi H., Birrien J.L., Naka J.,Yamanaka T., Laporte C., Nishimura K., Yeats C., Malagun S., Kia P., Oyaizu M. & Katayama T. (1999) Hydrothermal vent communities in the Manus Basin, Papua New Guinea: Results of the BIOACCESS cruises ‘96 & ‘98. InterRidge News, 8 (2), 12–18.
Hertlein L.G., Cox L.R. & Newell N.D. (1969) Superfamily Pectinacea Rafinesque, 1815. In: Moore R.C. (Ed.), Treatise on Invertebrate paleontology, part N, Mollusca 6, Bivalvia, The Geological Society of America, Boulder, N332–N383.
Hessler R.R. & Lonsdale P.F. (1991) Biogeography of Mariana Trough hydrothermal vent communities. Deep-sea Research, 38, 185–199.
Iredale T. (1939) Mollusca, part 1. In: Great Barrier Reef Expedition 1928–29, Scientific Reports, 5, British Museum Natural History, London, 209–425.
Knudsen J. (1970) The systematics and biology of abyssal and hadal Bivalvia. Galathea Report, Danish Science Press, Copenhagen, 11, 1–241.
Le Pennec G., Beninger P.G., Le Pennec M. & Donval A. (2003) Aspect of the feeding biology of the pectinacean Bathypecten vulcani, a peri-hydrothermal vent bivalve. Biology of feeding. Journal of the Marine Biological Association of the United Kingdom, 83, 479–482.
Le Pennec G., Le Pennec M., Beninger P.G. & Dufour S. (2002) Spermatogenesis in the archaic hydrothermal bivalve, Bathypecten vulcani, and comparison of spermatozoon ultrastructure with littoral pectinids. Invertebrate Reproduction and Development, 41, 13–19.
Le Pennec M., Herry A., Lutz R. & Fiala-Médioni A. (1988) Premières observations ultrastructurales de la branchie d””un Bivalve Pectinidae hydrothermal profond. Comptes Rendus de l””Académie des Sciences Paris, 307, série III, 627–633.
Little C.T.S. & Vrijenhoek R.C. (2003) Are hydrothermal vent animals living fossils ? Trends in Ecology and Evolution, 18, 582–588.
Lucas A. (1984) Développement contrôlé des Bivalves marins. Haliotis, 14, 143–158.
Mc Arthur A.G. & Tunicliffe V. (1998) Relics and antiquity revisited in the modern vent fauna. Geological Society Special Publication, 148, 271–291.
McKinney M.L. (1988) Heterochrony in Evolution. A multidisciplinary approach, Topics in Geobiology, Plenum Press, New York, 7, 348 pp.
McNamara K.J. (1995) Evolutionary change and heterochrony. John Wiley & Sons, Chichester, U.K., 286 pp.
Morton B. & Thurston M.H. (1989) The functional morphology of Propeamussium lucidum (Bivalvia: Pectinacea), a deep-sea predatory scallop. Journal of Zoology London, 218, 471–496.
Mullineaux L. S., Mills S.W. & Goldman E. (1998) Recruitment variation during a pilot colonization study of hydrothermal vents (9°50’N, East Pacific Rise). Deep-sea Research, Part 2, Tropical studies in Oceanography, 45, 441–464.
Newell N.D. (1969) Family Aviculopectinidae Meek & Hayden, 1864. In: Moore R.C. (Ed.), Treatise on Invertebrate paleontology, part N, Mollusca 6, Bivalvia, The Geological Society of America, Boulder, N335–N341.
Newman W.A. (1985) The abyssal hydrothermal vent invertebrate fauna: a glimpse of antiquity ? Biological Society of Washington Bulletin, 6, 231–242.
Roux M., Rio M, Schein E., Lutz R.A., Fritz L.W. & Ragone L.M. (1989) Mesures in situ de la croissance des bivalves et des vestimentifères et de la corrosion des coquilles au site hydrothermal de 13°N (dorsale du Pacifique oriental). Comptes Rendus de l’Académie des Sciences Paris, 308, série III, 121–127.
Schein E. (1989) Pectinidae (Mollusca, Bivalvia) bathyaux et abyssaux des campagnes BIOGAS (Golfe de Gascogne). Systématique et biogéographie. Annales de l’Institut océanographique de Paris, 65, 59–125.
Schein-Fatton E. (1985) Découverte sur la ride du Pacifique oriental à 13°N d’un Pectinidae (Bivalvia, Pteromorphia) d’affinités paléozoïques. Comptes Rendus de l’Académie des Sciences Paris, 301, série III, 491–496.
Schein-Fatton E. (1987) L’adaptation des Pectinidae à l’océan profond. Des faunes actuelles à l’interprétation des annales paléontologiques. Thèse n°87 PA 06, Université Pierre et Marie Curie, Paris VI, 1–250.
Schein-Fatton E. (1988) Un Pectinacea (Bivalvia) très primitif: Bathypecten vulcani, du site hydrothermal de 13°N (Pacifique oriental). Oceanologica Acta, volume spécial 8, 83–98.
Smith E.A. (1885) Report on the Lamellibranchiata. Challenger Reports, Edinburgh, Zoology, 13, 35, 341 pp.
Van Dover C.L., German C.R., Sperr K.G., Varson L.M. & Vrijenhoek R.C. (2002) Evolution and biogeography of deep-sea vent and seeps invertebrates. Science, 295, 1253–1257.
Waller T.R. (1972) The Pectinidae (Mollusca: Bivalvia) of Eniwetok Atoll, Marshall Islands. The Veliger, 14, 3, 221–264.
Waller T.R. (1978) Morphology, morphoclines and a new classification of Pteriomorphia (Mollusca: Bivalvia). Philosophical transctions of the Royal Society of London, B, 284, 345–365.
Waller T.R. (1984) The ctenolium of scallop shells: functional morphology and evolution of a key family-level character in the Pectinacea (Mollusca, Bivalvia). Malacologia, Philadelphia, 25, 203–219.
Waller T.R. (1986) A new genus and species of scallop (Bivalvia : Pectinidae) from off Somalia, and the definition of a new tribe Decatopectinini. The Nautilus, 100, 39–46.
Waller T.R. (1991) Evolutionary relationships among commercial scallops (Mollusca: Bivalvia: Pectinidae). . In: Shumway S.E. (Ed.), Scallops: Biology, Ecology and Aquaculture, Developments in aquaculture and fisheries science, 21, Elsevier, Amsterdam, 1–73.
Waller T.R. (1998) Origin of the molluscan class Bivalvia and a phylogeny of major groups. In: Johnson P.A. & Haggarth J.W.(Eds), Bivalves: an eon of evolution — Paleobiological Studies honouring Norman D. Newell, University of Calgary Press, Calgary, pp. 1–45.
Yonge C.M. (1967) Observations on Pedum spondyloideum (Chemnitz) Gmelin, a scallop associated with reef-building corals. Proceedings of the malacological Society of London, 37, 311–323.
Yonge C.M. (1981) On adaptive radiation in the Pectinacea with a description of Hemipecten forbesianus. Malacologia, Philadelphia, 21, 23–34.