부산대학교 도서관

To authenticate to the full-text of this article, please visit this link: http://dx.doi.org/10.1111/j.1475-4983.2009.00846.x Byline: IVAN J. SANSOM (*), C. GILES MILLER ([dagger]), ALAN HEWARD (,), NEIL S. DAVIES (,), GRAHAM A. BOOTH ([double dagger]), RICHARD A. FORTEY ([dagger]), FLORENTIN PARIS (s.) Keywords: Ordovician; pteraspidomorphs; Gondwana palaeocontinent; Sacabambaspis; Oman Abstract: Abstract: Over the past three decades Ordovician pteraspidomorphs (armoured jawless fish) have been recorded from the fringes of the Gondwana palaeocontinent, in particular Australia and South America. These occurrences are dominated by arandaspid agnathans, the oldest known group of vertebrates with extensive biomineralisation of the dermoskeleton. Here we describe specimens of arandaspid agnathans, referable to the genus Sacabambaspis Gagnier, Blieck and Rodrigo, from the Ordovician of Oman, which represent the earliest record of pteraspidomorphs from the Arabian margin of Gondwana. These are among the oldest arandaspids known, and greatly extend the palaeogeographical distribution of the clade around the periGondwanan margin. Their occurrence within a very narrow, nearshore ecological niche suggests that similar Middle Ordovician palaeoenvironmental settings should be targeted for further sampling. Author Affiliation: (*)Earth Sciences, University of Birmingham, Birmingham B15 2TT, UK; e-mail:i.j.sansom@bham.ac.uk ([dagger])Department of Palaeontology, The Natural History Museum, London SW7 5BD, UK; e-mails:g.miller@nhm.ac.uk andr.fortey@nhm.ac.uk ([double dagger])Petroleum Development Oman, Muscat, Oman; e-mail:graham.booth@pdo.co.om (s.)Geosciences, Universite de Rennes, 35042 Rennes, France; e-mail:florentin.paris@univ-rennes1.fr ([paragraph])Present address: Petrogas E&P, Muscat, Oman; e-mail:alan.heward@petrogas.com.om (**)Present address: Earth Sciences, Dalhousie University, Halifax, Nova Scotia B3H 3J5, Canada; e-mail:neil.s.davies@dal.ca Article History: Typescript received 25 February 2008; accepted in revised form 19 May 2008