A new protacanthopterygian fish from the Upper Cretaceous (Turonian) of the Pelotas Basin, southern Brazil F.J. de Figueiredo, V. Gallo * , A.F.P. Delarmelina Departamento de Zoologia, Instituto de Biologia, Universidade do Estado do Rio de Janeiro, Rua São Francisco Xavier, 524, 20550-013 Maracanã, Rio de Janeiro, Brazil article info Article history: Received 22 January 2010 Accepted in revised form 24 October 2011 Available online 3 November 2011 Keywords: Parawenzichthys minor gen. et sp. nov. Protacanthopterygii Turonian Pelotas Basin abstract The Turonian age in the Pelotas Basin is represented by the Atlântida Formation, which consists mainly of marine dark shales and siltstones with intervening layers of carbonates. It has yielded a neritic fish assemblage that includes lamniform, pycnodontid, cladocyclid, clupeomorph, basal euteleostean, dercetid, enchodontid and holocentrid remains. In this assemblage there is a small fish, here described as Parawenzichthys minor gen. et sp. nov. It is characterized by having a low and elongate body, prominent snout, drop-shaped nasal, smooth dermal bones, toothless jaws, a mandible-suspensorium joint placed at the posterior portion of the orbit, very small pleural ribs, and at least 50 smooth vertebrae. Although superficially very similar to Santanasalmo elegans, known from the Albian of the Araripe Basin, it is separated by a combination of features of skull and, particularly, in the caudal endoskeleton. The first uroneural shows reduced anterior outgrowth and is fused to the compound centrum (first preural þ ural centra), and the second uroneural is very long. There are six hypurals, the first of which is the largest. Taking into account the presence of derived conditions in the skull and caudal endoskeleton, the fish is assigned to Protacanthopterygii, sharing certain derived features with the argentinoid Wenzichthys congolensis from the non-marine Lower Cretaceous of Gabon (Africa). Ó 2011 Elsevier Ltd. All rights reserved. 1. Introduction The Pelotas Basin is a marginal passive basin extending from the southern Brazilian to the Uruguayan coast (Fig. 1). In Brazilian territory, its limits encompass an area of about 260,000 km 2 . The known palaeoichthyofauna is preserved in the Atlântida Formation (Table 1) of this basin. It is composed of a thick section of pelites (about 900 m), comprising dark grey shales, marls, and siltstones, deposited in a neritic palaeoenvironment of the outer shelf (Bueno et al., 2007). Calcareous nannofossils and palynomorphs indicate an age ranging from Late Albian to Early Turonian (Dias et al., 1994). However, the level in which the palaeoichthyofauna occurs is dated as Early Turonian, also based on inoceramids (Figueiredo et al., 2001; Figueiredo and Gallo, 2006; Gallo et al., 2006; Gallo-da- Silva and Figueiredo, 1999). The fish assemblage includes lamniforms, pycnodontids, cladocyclids, clupeomorphs, basal euteleosts, dercetids, enchodontids and holocentrids (Gallo et al., 2006). Although recent studies indicate spatiotemporal relations of this assemblage with others from Morocco and Mexico (Gallo et al., 2007; Blanco et al., 2008), a slender protacanthopterygian fish, until now not formally described, shares certain similarities with the argentinoid Wenzichthys congolensis known from the Cocobeach Formation of West Africa (Taverne, 1975, 1976). In this paper, we describe this fish as new genus and species and briefly furnish a comparison with certain basal euteleosteans. 2. Material and methods The material belongs to the Palaeozoological Collection of the Departamento de Zoologia of the Universidade do Estado do Rio de Janeiro, and is designated by the abbreviation Pz.UERJ, plus the regis- tration number 483. It consists of a partially complete and articulated specimen preserved in dark grey shale, corresponding to a core sample extracted at a sediment depth of around 4,000 m on the continental shelf in southern Brazil (Gallo et al., 2006). The specimen was prepared mechanically with needles, according to usual palaeontological tech- niques. Ethyl acetate was applied on the surface to enhance some skeletal structures. Pigmented peels of silicone rubber were produced to obtain positive relief of certain skeletal structures. The drawings were made using a camera lucida attached to a stereomicroscope. 3. Systematic palaeontology Teleostei Müller, 1844 Clupeocephala Patterson and Rosen, 1977 * Corresponding author. Tel.: þ55 2123340461. E-mail address: gallo@uerj.br (V. Gallo). Contents lists available at SciVerse ScienceDirect Cretaceous Research journal homepage: www.elsevier.com/locate/CretRes 0195-6671/$ e see front matter Ó 2011 Elsevier Ltd. All rights reserved. doi:10.1016/j.cretres.2011.10.009 Cretaceous Research 34 (2012) 116e123