ORIGINAL ARTICLE Revision of Chilean bathyal chitons (Mollusca: Polyplacophora) associated with cold-seeps, including description of a new species of Leptochiton (Leptochitonidae) Enrico Schwabe & Javier Sellanes Received: 2 February 2009 / Accepted: 19 August 2009 # Gesellschaft für Biologische Systematik 2010 Abstract The chiton fauna of Chile comprises 41 species, most of which inhabit shallow waters. The present paper gives a summary of all 14 chiton species reported from Chilean deep (bathyal to abyssal) waters, including some records that might be considered as doubtful. Leptochiton laurae n. sp. is formally established; it was formerly misidentified as L. americanus Kaas & Van Belle, 1985, but differs in the shape of the tail valve, less coarse sculpturing, in the girdle elements and radula armature. Two additional new species, Leptochiton sp. and Placi- phorella sp., are discussed. For Leptochiton medinae Plate, 1899, a lectotype is designated. Tripoplax balaenophila (Schwabe & Sellanes, 2004) n. comb. is transferred from Lepidozona Pilsbry, 1892, due to coarse sculpturing in the central areas and multi-slit insertion plates. Leptochiton belknapi Dall, 1878 and Tripoplax cowani Clark, 2008 are reported from the study region for the first time. The majority of the Chilean deep-water polyplacophorans are associated with hard substrates (authigenic carbonates) near methane seeps. The present report raises the global number of chiton species inhabiting chemosynthetic environments from 10 to 18, including some overlooked literature records from other regions. Keywords Polyplacophora . Systematics . Pacific Ocean . Chile . Deep water . Cold-seeps Abbreviations CASIZ California Academy of Sciences, Invertebrate Zoology, San Francisco, USA. CIEP Centro de Investigación en Ecosistemas de la Patagonia, Coyhaique, Chile. CMSA Concepción Methane Seep Area. FLMNH Florida Museum of Natural History, Gainesville, USA. JS second author ’ s reference collection. MNHNCL Museo Nacional de Historia Natural, Santiago de Chile, Chile. NHM National History Museum, London, United Kingdom. spm(s) specimen(s). SIO Scripps Institution of Oceanography, La Jolla, California, USA. UDEC Universidad de Concepción, Chile. UF University of Florida, Gainesville, USA. USNM United States National Museum of Natural History, Smithsonian Institution, Washington, D.C., USA. WAM Western Australian Museum, Welshpool, Australia. ZISP Zoological Institute of the Russian Academy of Sciences, St. Petersburg, Russia. ZMB Natural History Museum of Humboldt University, Berlin, Germany. E. Schwabe (*) Bavarian State Collection of Zoology, Muenchhausenstrasse 21, 81247 Muenchen, Germany e-mail: Enrico.Schwabe@zsm.mwn.de J. Sellanes Universidad Católica del Norte, Departamento de Biología Marina, Larrondo 1281, Coquimbo, Chile J. Sellanes Centre for Oceanographic Research in the Eastern South Pacific (COPAS), Universidad de Concepción, Casilla 160-C, Concepción, Chile Org Divers Evol DOI 10.1007/s13127-009-0002-6