Description of Calliotropis ceciliae new species (Gastropoda: Chilodontidae: Calliotropinae) from off Chile Claude Vilvens Scientific collaborator to the Muse ´ um national d’Histoire naturelle, Paris. Rue de Hermalle, 113 B-4680 Oupeye BELGIUM vilvens.claude@skynet.be Javier Sellanes Universidad Cato ´ lica del Norte, Facultad de Ciencias del Mar Larrondo 1281 Coquimbo, CHILE and Centro de Investigacio ´ n Oceanogra ´fica en el Pacı ´fico Sur-oriental (COPAS) Universidad de Concepcio ´n Concepcio ´ n, CHILE sellanes@ucn.cl ABSTRACT A new species of Calliotropis is described from the vicinities of the Concepcio ´ n Methane Seep Area (36  S) and from addi- tional material from off Antofagasta (northern Chile, 22  S). It is compared to C. pelseneeri pelseneeri Cernohorsky, 1977, and C. pelseneeri rossiana Dell, 1990, from the adjacent Antarctic area, which differ notably from the new species by having a thicker supra-peripheral spiral cord, more angulate whorls, and a more lamellose sculpture present in the subspecies pelseneeri. The new species is also separated from the wide- spread C. infundibulum (Watson, 1879) by having a weaker P1 spiral cord and narrower umbilicus with spiral cords inside. The radula of the new species is also typically calliotropine. Additional keywords: Seguenzioidea, deep-sea, methane seeps INTRODUCTION The genus Calliotropis is known to be very widespread and speciose: many new species, mainly from deep water, were described, e.g. from south western Indian Ocean (Vilvens, 2005, 2006), from the Philippines (Poppe et al., 2006), from Australia (Jansen, 1994), and from other areas of Indo-Pacific such as Taiwan, Indonesia, New Caledo- nia, Fiji and Vanuatu (Vilvens, 2004, 2007). The deep-water malacofauna of the SE Pacific, and in particular that of Chile, is still poorly known. A survey of the Trochoidea including the description of two new species was recently presented by Vilvens and Sellanes (2006). The new species described in that work come from the bathyal zone (850 m) Concepcio ´ n Methane Seep Area (CMSA). This area has been proven to be a faunal aggregation “hotspot” that includes about 30 species of molluscs (Sellanes et al., 2008). Many of these species were previously unknown, mainly the chemosymbiotic bivalves and some of the gastropods (reviewed in Sellanes et al., 2008). Five species of the group Trochoidea inhabiting this seep area are currently identified to specific level: Bathybembix macdonaldi (Dall, 1890), Margarites huloti Vilvens and Sellanes, 2006, Otukaia chilena Rehder, 1971, O. crustulum Vilvens and Sellanes, 2006, and Zetela alphonsi Vilvens, 2002. An additional species of the group, collected in the vicinities of the same area and in 2001 off Antofagasta, was tentatively assigned to the genus Calliotropis. These latter constitute the first records for the genus from off Chile. The geographically closest records are those of Dell (1990), who described or reported some Calliotropis species from the adjacent Antarctic area (Ross, Weddell, and Bellingshausen seas). The present paper aims to describe the new species of Calliotropis and to review the congeners for the South- eastern Pacific and adjacent Antarctic areas. MATERIALS AND METHODS Material of the present study consists of specimens obtained living (lv) from the dredge hauls performed by R/V VIDAL GORMA ´ Z during the VG-07 cruise at two sta- tions near the CMSA (36  S). Additional material was collected off Antofagasta (22  48.02 0 S, 70  36.71 0 W) in 1350 m during 2001 in a R/V SONNE expedition. Abbre- viations used are: H: shell height; W: shell width; HA: aperture height; TW: number of teleoconch whorls; spi- ral cords on teleoconch of the shells are labelled as P1, P2, ... etc., for primary cords (P1 being the most adapical) and S1, S2, ... etc., for secondary cords (S1 being the most adapical). Type specimens are deposited at Natural History Museum of Chile, Santiago (MNHNCL), Institut royal des Sciences naturelles de Belgique, Brussels, Belgium (IRSNB), and Muse ´um national d’Histoire naturelle, Paris, France (MNHN). SYSTEMATICS We follow herein the arrangement of Bouchet and Rocroi (2005) for the suprageneric allocation of THE NAUTILUS 124(2):107–111, 2010 Page 107