Mesozoic marine reptiles from the Iberian Peninsula Los reptiles marinos del Mesozoico de la Península Ibérica N. Bardet 1, X. Pereda Suberbiola 2 y J.I. Ruiz Omeñaca 3 1 UMR 5143 du CNRS, Muséum national d’Histoire naturelle, 57 rue Cuvier, C.P. 38, 75005 Paris, France. [email protected] 2 Departamento de Estratigrafía y Paleontología, Facultad de Ciencia y Tecnología, Universidad del País Vasco/EHU, Apdo. 644, 48080 Bilbao, Spain. [email protected] 3 Museo del Jurásico de Asturias, 33328 Colunga, Spain. [email protected] Abstract: A synthesis of the fossil record of Mesozoic marine reptiles from the Iberian Peninsula (Spain and Portugal) is provided for the first time. Though this fossil record appears poor compared to other European regions, it astonishes by its expanded stratigraphical range, from the Middle Triassic to the latest Cretaceous, as well as by its high-level taxonomical diversity, most clades being represented, i.e. thalattosaurs, sauropterygians, ichthyosaurians, mosasaurids, snakes, crocodyliforms and turtles. Key words: Thalattosauria, Sauropterygia, Ichthyosauria, Squamata, Crocodyliformes, Testudines, Spain, Portugal. Resumen : Se presenta por primera vez una síntesis del registro fósil de reptiles marinos mesozoicos en la Península Ibérica (España y Portugal). Aunque dicho registro pueda parecer pobre comparado con otras regiones europeas, es sorprendente por su amplio rango estratigráfico, desde el Triásico medio al Cretácico Superior, así como por su gran diversidad taxonómica a nivel de taxones de alto rango, estando representados la mayoría de los clados, a saber: talatosaurios, sauropterigios, ictiosaurios, mosasáuridos, serpientes, cocodrilos y tortugas. Palabras clave: Thalattosauria, Sauropterygia, Ichthyosauria, Squamata, Crocodyliformes, Testudines, España, Portugal. INTRODUCTION GEOGRAPHY AND GEOLOGY (Fig. 1) The first mentions of the discovery of Mesozoic Triassic – Marine reptile remains are abundant in marine reptile fossils in the Iberian Peninsula date from the Middle Triassic (Muschelkalk facies) and, to a lesser the second half of the XIX th century (Schulz, 1858 for extent, in the Upper Triassic (Keuper facies) of Spain. Spain; Sauvage, 1897-1898 for Portugal), roughly Up to now, they have not been unearthed in the Triassic coinciding with those made in the rest of Europe and of Portugal nor in the Lower Triassic of Spain. All linked to the Industrial Revolution engineering works. outcrops are located in the eastern part of the Iberian Since that time and though good exposures of marine Peninsula, having been found in the Autonomous Mesozoic rocks, the fossil record of Iberian marine Communities of Aragón (Huesca and Teruel provinces), reptiles remains quite poor – both quantitatively and Castilla-La Mancha (Cuenca, Albacete, Guadalajara and qualitatively – as compared to other European countries. Ciudad Real), Cataluña (Barcelona and Tarragona) and Indeed, Lagerstätten outcrops are unknown for Iberian Islas Baleares (Mallorca). The most fossiliferous marine reptiles, which are mainly represented by outcrops are those of Mont-ral-Alcover (Tarragona, isolated and fragmentary specimens (vertebrae and Ladinian, Fig. 1, n°4), which has yielded the greatest teeth), producing very few determinable infra-familial number of specimens and taxa; Estada (Huesca, Mid- taxa. However, the Iberian record of Mesozoic marine Triassic, n°1) which is the oldest known one; and reptiles astonishes by its expanded stratigraphical range, Manzarena (Teruel, Carnian, n°8), which is the only from Middle Triassic to uppermost Cretaceous, and by outcrop of sure Late Triassic age from the Iberian its high-level taxonomical diversity, with most of the Peninsula. major clades being represented. The aim of this paper is to present an overview of the Mesozoic marine reptiles Jurassic – Jurassic outcrops are more numerous of the Iberian Peninsula, both on a spatiotemporal and a than Triassic ones, being known both in Portugal and systematical perspective. The bibliographic database Spain. They range from the Lower Liassic (Hettangian) used is Quesada et al . (1998) for Spain and Crespo to the Upper Malm (Tithonian). Lower Jurassic outcrops (2002) for Portugal, complemented by more recent are abundant, especially those of Pliensbachian age, a references when necessary. stage worldwidly considered as very poor in marine reptile remains. Upper Jurassic outcrops are also well represented, especially those of Kimmeridgian age. Geo-Temas 10, 2008 (ISSN: 1567-5172) 1246 N. BARDET ET AL. Middle Jurassic marine reptiles are poorly known and represented by Callovian remains only. Contrary to Triassic fossiliferous sites, the Jurassic ones are concentrated on the western part of the Iberian Peninsula, and more especially on the Atlantic Coast of Portugal (Central region) and Spain (Asturian coast). Specimens from Spain come from Asturias, Castilla y León (Soria province), La Rioja, Aragón (Zaragoza and Teruel) and Valencia. Those from Portugal have been unearthed from the Central (Aveiro, Coimbra and Leiria districts), Lisboa (Lisboa district) and Algarve (Faro district) regions. The most productive levels are those of: 1) the Lias of the Asturias coast (Fig. 1, n°16) and of the Central region of Portugal (n°35-38, 40, 41, 43, 44); and 2) the Kimmeridgian of the same areas of Spain FIGURE 1. Map of the main localities with Mesozoic marine reptiles (n°17, 18) and Portugal (n°38, 41, 42, 45). The first in Spain (provinces in brackets) and Portugal (districts in brackets). SPAIN - Triassic : 1: Estada (Huesca); 2: Aiguafreda (Barcelona); 3: marine reptile remains of Iberia were found in these Olesa (Barcelona); 4: Mont-ral-Alcover (Tarragona); 5: Riba de areas (Schulz, 1858; Sauvage, 1897-1898). Santiuste-Tordelrábano (Guadalajara); 6: Rillo de Gallo (Guadalajara); 7: Royuela (Teruel); 8: Manzanera, Torrijas (Teruel); Cretaceous – Marine reptile fossils are rather scarce 9: Valdemeca (Cuenca); 10 : Boniches, Cañete (Cuenca); 11 : Henarejos (Cuenca); 12 : Sóller (Mallorca); 13 : Alcázar de San Juan in the Cretaceous of the Iberian Peninsula and come (Cuidad Real); 14 : Alpera (Albacete); 15 : Bienservida-Villarrodrigo from the Lower Cretaceous (Hauterivian to Aptian, (Albacete). Jurassic : 16 : Villaviciosa (Asturias); 17 : Colunga including Wealden facies) and Upper Cretaceous rocks (Asturias); 18 : Ribadesella (Asturias); 19 : Valgañón (La Rioja); 20 : (Cenomanian, Santonian to Maastrichtian). Ólvega (Soria); 21 : Ricla (Zaragoza); 22 : Obón (Teruel); 23 : Buñol (Valencia). Cretaceous : 24 : San Pantaleón de Losa (Burgos), Bóveda (Álava); 25 : Castillo-Lasarte (Álava); 26 : Jáuregui (Álava); 27 : Laño The outcrops are located in the País Vasco (Álava), (Condado de Treviño); 28 : Ortigosa de Cameros (La Rioja); 29 : Galve Castilla y León (Burgos and Condado de Treviño), La (Teruel); 30 : Castellote, Las Parras de Castellote (Teruel); 31 : Alcalá Rioja, Castilla-La Mancha (Cuenca), Aragón (Teruel) de la Selva (Teruel); 32 : Morella, Todolella (Castellón); 33 : Las Hoyas (Cuenca); 34 : Benagéber (Valencia). and Valencia (Castellón and Valencia provinces) in PORTUGAL - Jurassic : 35 : Casal Comba (Aveiro); 36 : Cadima, Spain, and in the Central (Aveiro and Coimbra Murtede (Coimbra); 37 : Alhadas (Coimbra); 38 : Condeixa-a-Nova/ districts), Lisboa (Lisboa district) and Algarve (Faro Miranda do Corvo, Cezimbra (Coimbra); 39 : Pombal (Leiria); 40 : Foz district) regions of Portugal. The most fossiliferous sites da Ribeira, Agua de Madeiros (Leiria); 41 , Praia N.S. da Victoria, Pintanheira, Fervença, Romão (Leiria); 42 : Guimarota (Leiria); 43 : are those of: 1) the latest Cretaceous of the Álava and Alvaiázere (Leiria); 44 : Tomar (Santarém); 45 : Cesareda (Leiria); 46 : Burgos provinces (Fig.1, n°24-26), mainly the Laño Lourinhã, Praia de Santa Cruz (Lisboa); 47 : Vila Franca do Rosário quarry (n°27), and of Aveiro (n°49) and Coimbra (n°51, (Lisboa); 48 : Malhão (Faro). Cretaceous : 49 : Aveiro (Aveiro); 50 : 52) districts; 2) the Cenomanian of Lisboa (n°53); and Chousa do Fidalgo (Aveiro); 51 : Viso (Coimbra); 52 : Taveiro (Coimbra); 53 : Pendao/Figueira, Cacém, São Pedro do Estoril 3) the Wealden of Valencia (n°34). (Lisboa); 54 : Alcantara (Faro). SYSTEMATICS Placodonts are mainly known by characteristic rounded, low, crushing teeth (Pinna, 1990 in Quesada et Most Mesozoic marine reptile groups are al., 1998; Rieppel, 2000). Two genera are known: the represented in the fossil record of the Iberian Peninsula: placodontoid Paraplacodus in the Muschelkalk/ thalattosaurs, sauropterygians, ichthyopterygians, Keuper? of Henajeros (n°11) and the cyamodontoid squamates, crocodyliforms and chelonians. ?Psephoderma in the Ladinian of Mont-ral-Alcover (n°4). Cyamodontoids are also represented by Thalattosauria – The only mention of this Triassic placochelyids in the Muschelkalk of Bienservida- group has been made in the Ladinian of Mont-ral- Villarrodrigo (n°15) and in the Muschelkalk/Keuper? of Alcover (Fig. 1, n°4) (Rieppel y Hagdorn, 1998). Valdemeca (n°9), Riba de Santiuste-Tordelrábano (n°5), Rillo de Gallo (n°6) and Alcázar de San Juán (n°13); Sauropterygia – Sauroptergygia is the best known and by cyamodontids in the Middle Muschelkalk of clade of marine reptiles of the Iberian Peninsula. It Alpera (n°14) and in the Carnian of Manzarena (n°8). includes remains of Triassic pachypleurosaurs, Finally, indeterminate remains of Placodontia have been placodonts, nothosaurs, and pistosaurs, and of Jurassic unearthed in the Muschelkalk