ORIGINAL PAPER Theropod teeth diversity from the Villar del Arzobispo Formation (Tithonian–Berriasian) at Riodeva (Teruel, Spain) Francisco Gascó & Alberto Cobos & Rafael Royo-Torres & Luis Mampel & Luis Alcalá Received: 31 October 2011 / Revised: 15 February 2012 / Accepted: 13 March 2012 # Senckenberg Gesellschaft für Naturforschung and Springer 2012 Abstract Riodeva sites (Villar del Arzobispo Fm) in Teruel, Spain, have revealed themselves as a window through which to gain a better understanding of the Iberian dinosaurs of the Jurassic–Cretaceous transition. Nevertheless, the theropod re- cord from this Formation is scarce. Based on our study of a sample of theropod teeth recovered from different Riodevan sites, we have come to the conclusion that dinosaur assemb- lages in Riodeva include at least three different kinds of theropods: big non-coelurosaur tetanurans, middle-sized allo- saurids and small dromaeosaurs. These three types of thero- pods represent new elements in the record of dinosaurs, which until now includes sauropods (turiasaurians, diplodocids, macronarians), stegosaurs and ornithopods. Keywords Theropoda . Teeth . Villar del Arzobispo Fm . Riodeva . Allosauroidea Introduction Many theropods from the Middle and Late Jurassic and also from the Jurassic–Cretaceous transition have been described for Europe. The presence of the genera Torvosaurus, Cerato- saurus and Allosaurus in Portugal has been proven, together with an undetermined dromaeosaurian (Antunes and Mateus 2003; Malafaia et al. 2010). In addition, two new genera have also been described, i.e. Lourinhanosaurus (Mateus 1998) and Aviatyrannis (Rauhut 2003). The main Allosaurus record in Portugal consists of a collection of cranial and postcranial remains from several individuals from the Andrés and Cambelas sites which have been assigned to Allosaurus fragilis (Dantas et al. 1999; Malafaia et al. 2007, 2009; Pérez-Moreno et al. 1999). Other remains include a small maxilla from Mina de Guimarota, inter- preted as belonging to a juvenile Allosaurus (Rauhut and Fechner 2005) and a posterior fragment of a skull from Vale Frades, Lorinha, being the holotype of Allosaurus euro- paeus (Mateus et al. 2006). The latter species is considered to be the junior synonym of an Allosaurus fragilis (Malafaia et al. 2007). A collection of isolated teeth from Porto das Barcas and Guimarota have also been assigned to Allosaurus (Rauhut 2000; Rauhut and Kriwet 1994; Zinke 1998). In Germany, the probable presence of velociraptorine dromaeosaurians has been reported based on isolated teeth (Van der Lubbe et al. 2009) from the type locality of Europasaurus holgeri (Laven 2001; Sander et al. 2006). Apart from these, several theropods were described during the nineteenth century from the Solnhofen limestone, such as Archaeopteryx (Meyer 1861), Compsognathus (Wagner 1859) and Juravenator (Göhlich and Chiappe 2006). Theropod bones in Spain from the Late Jurassic to Early Cretaceous are scarce. In Asturias, a caudal vertebra and two teeth have been described from the Vega Formation (Ruiz-Omeñaca 2010), and ten teeth have been found in the Lastres Formation (Ruiz-Omeñaca et al. 2009). Only some of these have been identified as Carnosauria? indet. (Ruiz-Omeñaca et al. 2009) The vast majority of known theropods from the Late Juras- sic come from the Morrison Formation in North America, such as Ceratosaurus (Marsh 1884), Allosaurus (Marsh 1877), Saurophaganax (Chure 1995), Torvosaurus (Galton and Jensen 1979), Marshosaurus (Madsen 1976), Stokesosaurus (Madsen 1974), Ornitholestes (Osborn 1903), Coelurus (Marsh 1879), Tanycolagreus (Carpenter et al. 2005), Elaph- rosaurus (Chure 2001) and Koparion (Chure 1994). This article is a contribution to the special issue "Proceedings of the 9th EAVP Meeting, Heraklion 2011" F. Gascó (*) : A. Cobos : R. Royo-Torres : L. Mampel : L. Alcalá Fundación Conjunto Paleontológico de Teruel-Dinópolis, Avda. Sagunto, s/n, 44002 Teruel, Spain e-mail: gasco@fundaciondinopolis.org Palaeobio Palaeoenv DOI 10.1007/s12549-012-0079-3