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Vertebrate Palaeontologists

European Association European

10

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Annual Meeting of the of Meeting Annual Royo-Torres, R., Gascó, F. and Alcalá, L., coord. (2012). 10th Annual Meeting of the European Association of Vertebrate Palaeontologists. ¡Fundamental! 20: 1–290.

EDITOR: © Fundación Conjunto Paleontológico de Teruel – Dinópolis COORDINATION: Rafael Royo-Torres, Francisco Gascó and Luis Alcalá. DISEÑO Y MAQUETA: © EKIX Soluciones Gráficas DL: TE–72–2012 ISBN–13: 978–84–938173–4–3

PROJECT: CGL 2009 06194-E/BTE Ministerio de Ciencia e Innovación

Queda rigurosamente prohibida, sin la autorización escrita de los autores y del editor, bajo las sanciones establecidas en la ley, la reproducción total o parcial de esta obra por cualquier medio o procedimiento, comprendidos la reprografía y el tratamiento informático. Todos los derechos reservados.

2 A new specimen of Allodaposuchus sp. () from the late of (Serraduy, )

Eduardo Puértolas-Pascual, Penélope Cruzado-Caballero, José Ignacio Canudo, Miguel Moreno-Azanza, José Manuel Gasca, Diego Castanera and Jara Parrilla

Grupo Aragosaurus-IUCA, Dpto. Ciencias de la Tierra, Área de Paleontología, Facultad de Ciencias, Universidad de Zaragoza 50009 Zaragoza (Aragón). [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; [email protected]; [email protected]

Figure 1. Geological and geographical situation: Map of the outcrops (in green) within the South Pyrenean Central Unit. The black box Introducción marks the location area and the red start is the paleontological site Amor-3.

The Maastrichtian of the Tremp Basin (Pyrenees, NE Spain) vertebrate fossil sites from outcroups located between the villages presents one of the richest Mesozoic vertebrate fossil assemblages of Serraduy and , 12 km northwest of Arén. Dinosaur from the Iberian Peninsula. In recent years, great efforts have been remains, including hadrosaurids, undetermined ornithopods, avian made in order to reconstruct the vertebrate succession of the Pyrenees theropods and sauropods, in addition to chelonian, neosuchian and at the end of the . The vertebrate fossil record closed to eusuchian crocodilomorph remains have been recovered. Especially the K/P boundary is very scarce worldwide, and the Pyrenees is one interesting is a nearly complete eusuchian crocodylomorph skull of the few areas with abundant vertebrate fossils remains from this (AM3-15), provisionally housed in the Museo Paleontolológico de la time interval. Within this record, it is noticeable the presence of a Universidad de Zaragoza. The aim of this paper is the description of well-known vertebrate fossil assemblage from Arén (Huesca, Spain). the skull AM3-15 and the discussion about its systematic position. Two lambeosaurine dinosaurs, Arenysaurus (Pereda-Suberbiola et al., 2009) and Blasisaurus (Cruzado-Caballero et al., 2010); and the Geographical and Geological Context Crocodyloid Arenysuchus (Puértolas et al., 2011) have been described in the Blasi and Elías sites from Arén. Fossil remains of AM3-15 was recovered from Amor-3 site, located to the north bony fish, lizards, amphibians, turtles and eggshell fragments have of the Pyrenees near the village of Serraduy del Pon (NE Huesca, been also reported (López-Martínez et al., 2001; Blain et al., 2010). Spain). The study area is placed in the northern flank of the Tremp syncline, in the Tremp Basin within the South Pyrenean Central The Aragosaurus-IUCA research team of the University of Unit (Fig. 1). Zaragoza has carried new palaeontological surveys in the northwest sector of the Tremp Group within the Huesca province during Stratigraphically, the site is located within the Tremp Group. the last decade. This fieldwork has allowed the discovery of new In its lower part, the Tremp Group is superimposed upon and

199 interdigitates laterally with the mixed platform marine deposits of the Arén Formation, late -Maastrichtian in age (Upper Cretaceous). Overlaying the Tremp Group there are marly sediments of the marine Cadí Formation, laterally equivalent to the Figols Group, Ilerdian in age (Lower ).

The skull was recovered in a level of microconglomerates in the middle-upper part of the lower red unit (Conqués Formation) of the Tremp Group, closely placed to the K/P boundary. This Formation is interpreted as an alluvial plain environment. This area has been correlated with the Arén sites, which are dated as late Maastrichtian in age (Pereda-Suberbiola et al., 2009).

Systematic Palaeontology

Figure 2. Allodaposuchus sp. from Amor-3, AM3-15 (Late Maastrichtian Hay, 1930 of Pyreenes). Dorsal (A) and ventral (B) view of AM3-15. Anatomical Eusuchia Huxley, 1875 abbreviations: bo, basioccipital; ch, choana; cqp, cranioquadrate passage; Allodaposuchus Nopcsa, 1928 ec, ectopterygoid; en, external naris; ex, exoccipital; f, frontal; fa, foramen Allodaposuchus sp. aereum; fm, foramen magnum; if, incisive foramen; itf, infratemporal fenestra; j, jugal; l, lacrimal; ls, laterosphenoid; m, maxilla; n, nasal; op, occlusion pit; or, Type : Allodaposuchus precedens Nopcsa, 1928. orbit; p, parietal; pf, prefrontal; pl, palatine; pm, premaxilla; pmn, premaxillary- Referred material: AM3-15 (Fig. 2), a nearly complete skull. maxillary notch; po, postorbital; pob, postorbital bar; pt, pterygoid; q, quadrate; qj, quadratojugal; qjs, quadratojugal spine; sof, suborbital fenestra; Description sq, squamosal; stf, supratemporal fenestra.

The skull (Fig. 2) is fairly complete and well preserved, slightly wider than long. The skull table is subrectangular and it has although some elements are variably damaged or missing. The rounded anterolateral corners and posteriorly parallel lateral margins, surface is generally not abraded allowing us to confidently interpret and its dorsal surface is planar in general with a slightly concave the position of the most of the major sutures. However some parts, depression medially. The dorsal surface of the skull displays well- such as the snout, are affected by the recent action of roots. developed ornamentation, comprising pits and grooves. These grooves are especially large and deep on the dorsal surface of the frontal. The The skull is brevirostrine, with a total length of 40 cm. The teeth are conical, subcircular in section, rather slender, pointed and dorsal and lateral outline of the snout has two marked concavities, with smooth mesiodistal keels delimited by vertical grooves. developed respectively in the middle of the skull (to the height of the sixth maxillary tooth) and in the lateral maxillary-premaxillary suture. Discussion The region anterior to the orbit is slightly upturned, but structures such as a median boss, preorbital ridges and canthii rostralii are not Eusuchia is the only of crocodylomorphs that lived in developed. The posterior and the right lateral edges of the skull table the Mesozoic and has representatives that are still extant. The are incomplete, but can be interpreted as the skull table appears to be basal members of Eusuchia may have had a Laurasian origin at

200 least since the Barremian (Buscalioni et al., 2011), coming to consideration. The most striking difference of the Serraduy taxon dominate the crocodylomorphs associations in Europe and North (AM3-15) with the skulls of Allodaposuchus from France (MDE/ America in the Upper Cretaceous. During the Cenozoic they CM-616; Martin, 2010) and Romania (PSMUBB V 438; Delfino et colonized other continents, especially tropical areas, replacing the al., 2008) is the festooned profile. The outline of the skull in dorsal rest of the Mesozoic crocodylomorph faunas. This joint presence view of PSMUBB V 438 and MDE/CM-616 is characterized by of eusuchians, especially in Europe and also in North America, a wide posterior sector nearly uniformly tapering in an anterior suggests the existence of a common ancestor for the members of direction up to the level of the anterior rim of the naris. In contrast, this clade, which evolved in one of these two continents. AM3-15 has a much broader snout and a clear festooned outline. This outline could be somewhat similar to the reconstruction The presence of the eusuchian Allodaposuchus is proposed by Buscalioni et al. (2001) for fragmentary cranial restricted to Europe, mainly to Romania (including the type- remains from Spain and France. The maxillary-premaxillary locality), France and Spain. The Allodaposuchus record comprises concavity (visible in lateral and dorsal view) is produced by a notch at least three nearly complete skulls (including the skull described behind the last premaxillary tooth, and in palatal view there is a in this paper) and other cranial remains. Currently, the genus pit (best marked in the left maxilla) placed medially to this notch. Allodaposuchus is represented by a single species, A. precedens, Another major difference is related to the premaxillary dentition. although some authors discussed the possibility that there could As yet, all specimens of Allodaposuchus had five premaxillary be different species (Buscalioni et al., 2001; Martin and Buffetaut, teeth, however AM3-15 only has four premaxillary alveoli. Also, 2005; Delfino et al., 2008b; Martin, 2010). the postorbital bar is not markedly slender to that described in the Romanian skulls, but it is still thinner than in , which is According to the revised diagnosis of Delfino et al. (2008), considered massive. The morphology of the bar is quite similar to AM3-15 shares with Allodaposuchus the following diagnostic the Spanish Allodaposuchus described by Buscalioni et al., (2001), characters: presence of a cranioquadrate passage (or canalis being subovate in cross-section and divided in two laminae, one quadratosquamosoexoccipitalis) laterally open, broader than facing anteriorly and the other lateroposteriorly. The external naris in vectiana, that it is represented by a sulcus; is large, but unlike the taxa from Romania and France, the naris is quadrate and squamosal not in contact in the posterior otic oval shaped and longer than wide. In addition, the naris seems to region and separated by the exoccipital, which forms part of be more dorsally oriented than anterodorsally. The shape and size the cranioquadrate passage; presence of bosses on paroccipital of the orbits of the AM3-15 are also slightly different. The orbits processes, but less developed than in Hylaeochampsa vectiana; of the rest of skulls from France, Spain and Romania are relatively orbital margins slightly upturned; occlusion pattern in line; a shallow large, broad and subcircular. Nonetheless, the orbits of the skull fossa or shelf at the anteromedial corner of the supratemporal from Serraduy are much smaller and elongated because the frontal fenestra; size of the maxillary alveoli increasing up to the fourth; is much wider in the interorbital region. quadrate-pterygoid suture linear from basisphenoid to foramen ovale; quadrate foramen aereum far from the dorsomedial edge; Conclusions the same teeth morphology; fourteen maxillary teeth; and a large size brevisrotrine skull (40 cm in length). AM3-15 is the first complete skull of an adult of Allodaposuchus found in the upper Maastrichtian of the Nevertheless, there are some differences between AM3-15 southern Pyrenees. The morphology of AM3-15 is different and the rest of European Allodaposuchus that must be taken into from the specimens of Allodaposuchus described in the Upper

201 Cretaceous of Europe. There are notable morphological CRUZADO-CABALLERO, P., PEREDA-SUBERBIOLA, X. and variations among the remains of Romania, France and Spain, RUIZ-OMEÑACA, J.I. 2010. Blasisaurus canudoi gen. et sp. so there could be probably at least two or three different species nov., a new lambeosaurine dinosaur (Hadrosauridae) from the of Allodaposuchus. Nonetheless, due the few remains found, Latest Cretaceous of Arén (Huesca, Spain). Canadian Journal its fragmentary nature and the absence of clearly juvenile of Earth Sciences, 47(12): 1507-1517. individuals, ontogenetic or intraspecific variations can not be DELFINO, M., CODREA, V., FOLIE, A., DICA, P., GODEFROIT, excluded. P. and SMITH, T. 2008b. A complete skull of Allodaposuchus precedens Nopcsa, 1928 (Eusuchia) and a reassessment of Acknowledgements the morphology of the taxon based on the Romanian remains. Journal of Vertebrate Paleontology, 28: 111-122. This paper forms part of the projects CGL2007-62469 and LÓPEZ-MARTÍNEZ N., CANUDO J.I., ARDÉVOL L., PEREDA- CGL2010-16447, subsidized by the Spanish Ministry of Economy SUBERBIOLA X., ORUE-ETXEBARRÍA X., CUENCA- and Competitiveness, the European Regional Development BESCÓS G., RUIZ-OMEÑACA J.I., MURELAGA X. and Fund, the Government of (“Grupos Consolidados” and FEIST M. 2001. New dinosaur localities near the Cretaceous/ “Dirección General de Patrimonio Cultural”) and the “Instituto de Tertiary boundary (Arén south central Pyrenees, Spain). Estudios Altoaragoneses”. Cretaceous Research, 22: 41-61. MARTIN, J.E. and BUFFETAUT, E. 2005. An overview of the References crocodilian assemblage from Cruzy, southern France. Kaupia, 14: 33-40 BLAIN H.A., CANUDO J.I., CUENCA-BESCÓS G. and LÓPEZ- MARTIN, J.E. 2010. Allodaposuchus NOPCSA 1928 (Crocodylia, MARTÍNEZ N. 2010. Amphibians and squamates from the Eusuchia) from the Late Cretaceous of southern France and its latest Maastrichtian (Upper Cretaceous) of Blasi 2 (Huesca, relationships to . Journal of Vertebrate Paleontology, Spain). Cretaceous Research, 31: 433-446. 30(3): 756-767. BUSCALIONI, A.D., ORTEGA, F., WEISHAMPEL, D.B. PEREDA-SUBERBIOLA, X., CANUDO, J.I., CRUZADO- and JIANU, C.M. 2001. A revision of the crocodyliform CABALLERO, P., BARCO, J.L., LÓPEZ-MARTÍNEZ, N., Allodaposuchus precedens from the Upper Cretaceous of OMS, O. and RUIZ-OMEÑACA, J.I. 2009. The last hadrosaurid the Haţeg Basin, Romania. Its relevance in the phylogeny of dinosaurs of Europe: A new lambeosaurine from the Uppermost Eusuchia. Journal of Vertebrate Paleontology, 21: 74-86. Cretaceous of Aren (Huesca, Spain). Comptes Rendus Palevol, BUSCALIONI, A.D., PIRAS, P., VULLO, R., SIGNORE, M. and 8(6): 559-572. BARBERA, C. 2011. Early eusuchia from PUÉRTOLAS, E., CANUDO, J.I. and CRUZADO-CABALLERO, the vertebrate-rich Plattenkalk of Pietraroia (Lower Albian, P. 2011. A New Crocodylian from the Late Maastrichtian of southern Apennines, Italy). Zoological Journal of the Linnean Spain: Implications for the Initial Radiation of Crocodyloids. Society, 163: S199-S227. PLoS ONE, 6(6): e20011.

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