A new actinopterygian fauna from the latest Cretaceous of Quintanilla la Ojada (Burgos, Spain) Ana BERRETEAGA Universidad del País Vasco/EHU, Facultad de Ciencia y Tecnología, Departamento de Estratigrafía y Paleontología, Apartado 644, SP-48080 Bilbao (Spain) and Universidad de Alcalá de Henares, Facultad de Ciencias, Departamento de Geología, Plaza San Diego s/n, SP-28801 Alcalá de Henares (Spain) [email protected] Francisco José POYATO-ARIZA Universidad Autónoma de Madrid, Departamento de Biología, Unidad de Paleontología, Cantoblanco, SP-28049 Madrid (Spain ) [email protected] Xabier PEREDA-SUBERBIOLA Universidad del País Vasco/EHU, Facultad de Ciencia y Tecnología, Departamento de Estratigrafía y Paleontología, Apartado 644, SP-48080 Bilbao (Spain) [email protected] Berreteaga A., Poyato-Ariza F. J. & Pereda-Suberbiola X. 2011. — A new actinopterygian fauna from the latest Cretaceous of Quintanilla la Ojada (Burgos, Spain). Geodiversitas 33 (2): 285-301. DOI: 10.5252/g2011n2a6. ABSTRACT We describe a new actinopterygian fauna from the uppermost Cretaceous of Quintanilla la Ojada (Burgos, Spain), in the Villarcayo Sinclynorium of the Basque-Cantabrian Region. It consists mostly of isolated teeth of pycnodon- tiforms (cf. Anomoeodus sp., Pycnodontoidea indet.), amiiforms (cf. Amiidae indet.) and teleosteans (elopiforms: Phyllodontinae indet., Paralbulinae indet.; KEY WORDS aulopiforms: Enchodontidae indet., plus fragmentary fi n spines of Acantho- Osteichthyes, Pycnodontiformes, morpha indet.). Paralbulinae teeth are the most abundant elements in the fossil Amiiformes, assemblage. All the remains are disarticulated and show intense post-mortem Elopiformes, Aulopiformes, abrasion. Th e fossil association has been found in dolomite sandstones that are Acanthomorpha, laterally correlated with the Valdenoceda Formation (Lower to basal Upper Maastrichtian, Maastrichtian) of the Castilian Ramp. Th e observed taphonomic features are Iberian Peninsula, Basque-Cantabrian coherent with the sedimentological interpretation of the fossiliferous beds as Region. coastal deltaic deposits. GEODIVERSITAS • 2011 • 33 (2) © Publications Scientifi ques du Muséum national d’Histoire naturelle, Paris. www.geodiversitas.com 285 Berreteaga et al. RÉSUMÉ Une nouvelle faune d’actinoptérygiens du Crétacé supérieur de Quintanilla la Ojada (Burgos, Espagne). Une nouvelle faune d’actinoptérygiens du Crétacé supérieur de Quintanilla la Ojada (Burgos, Espagne), localité située dans le Synclinorium de Villarcayo dans la région basco-cantabrique, est décrite ici. La plupart du matériel correspond à des dents isolées de pycnodontiformes (cf. Anomoeodus sp., Pycnodontoidea indet.), d’amiiformes (cf. Amiidae indet.) et de téléostéens (Elopiformes : Phyllo- dontinae indet., Paralbulinae indet. ; Aulopiformes : Enchodontidae indet., ainsi que des fragments d’épines d’Acanthomorpha indet.). Les dents de Paralbulinae MOTS CLÉS Osteichthyes, sont les éléments les plus abondants de l’association fossile. Tous les restes sont Pycnodontiformes, désarticulés et ont subi une abrasion post-mortem intense. Les fossiles ont été Amiiformes, Elopiformes, trouvés dans des dolomies sableuses qui sont corrélées latéralement avec la For- Aulopiformes, mation Valdenoceda (Maastrichtien inférieur à base du Maastrichtien supérieur) Acanthomorpha, de la Rampe Norcastillane. Les caractéristiques taphonomiques observées sont Maastrichtian, péninsule Ibérique, cohérentes avec l’interprétation sédimentologique des couches fossilifères comme région basco-cantabrique. ayant été déposées dans un milieu deltaïque côtier. INTRODUCTION work in progress). Th e present paper aims to describe the actinopterygian fauna that occurs in this new ver- Upper Cretaceous marine localities that have yielded tebrate site, which consists mostly of teeth of pycno- actinopterygian remains are presently rather scarce dontiforms, amiiforms, elopiforms, and aulopiforms, in the sedimentary basins of Spain (see Poyato-Ariza plus fragmentary acanthomorph spines. et al. 1999a). One of the most important known sites is Albaina, located in the Laño quarry (Condado de Treviño; area situated within the Basque Country but MATERIAL AND METHODS administered by the province of Burgos), where pyc- nodontiform and teleostean fossils have been found Th e vertebrate fossil remains of Quintanilla la Ojada in Upper Maastrichtian marine levels (Poyato-Ariza (Burgos) have been collected since 2002. Some teeth et al. 1999b). In the same quarry, the Upper Campa- were picked up in the fi eld (or extracted from the nian to lowermost Maastrichtian fl uviatile deposits of matrix after bulk rock processing), but most of the the Laño site have yielded scarce lepisosteiform and remains were obtained by screen-washing of the teleostean remains (Cavin 1999). Th us, the osteich- sediment. About 300 kg of sediment were washed thyan fossils of the Laño quarry occur at two distinct through 2 mm, 1 mm and 0.5 mm stainless steel stratigraphic horizons and were accumulated in quite meshes with running water in order to search for diff erent circumstances; both Albaina and Laño are microremains. Th e fi ne fraction was washed again part of the Miranda-Treviño Synclinorium (Baceta using a hand sieve of 0.25 mm. Th e sorting of the et al. 1999). Recently, additional marine fi sh-bearing teeth and other microremains was made by means localities of Late Cretaceous age have been discovered of stereomicroscopes. Th e material is housed in the in the Basque-Cantabrian Region (López-Horgue & laboratory of the Departamento de Estratigrafía y Poyato-Ariza 2005, work in progress). Th e fossil as- Paleontología of the Universidad del País Vasco/ sociation of the Maastrichtian locality of Quintanilla Euskal Herriko Unibertsitatea (Bilbao) (EHUEP). la Ojada (Burgos) is composed of actinopterygian, About 200 actinopterygian isolated teeth and a few selachian, and reptile remains (Berreteaga et al. 2010, fi n spine fragments are known. 286 GEODIVERSITAS • 2011 • 33 (2) New actinopterygian fauna from Spain N Paleozoic Bay of Biscay Permian and Triassic Santander Bayonne Keuper (diapir) Hettangian- San Sebastián Kimmeridgian (Marine Jurassic megasequence) C Bilbao CM Upper Tithonian to Barremian (Purbeck & AM Weald megasequences) Ebro Aptian-Albian to Quintanilla la Ojada Reservoir Vitoria Lower Cenomanian * Pamplona Late Albian-Santonian Albaina P volcanics V * Tertiary Ebro U Middle Cenomanian to Tertiary Duero Basin Maastrichtian Basin Logroño Tertiary Iberian Burgos Peninsula Principal fault 50 km * Vertebrate sites C Cabuerniga fault P Pamplona fault Basque Massifs (emerged areas U Ubierna fault CM affected by erosion) V Villela fault AM Asturian Massif FIG. 1. — Geological map of the Basque-Cantabrian Region showing the location of the actinopterygian sites mentioned in the text. LOCATION AND GEOLOGICAL SETTING drichthyans and osteichthyans (López-Horgue & Quintanilla la Ojada is located in the northern part of Poyato-Ariza 2005, work in progress). Burgos province (Losa Valley), approximately 22 km Th e Cretaceous-Tertiary deposits in the northwest east and 14 km northeast of Villarcayo and Trespaderne limb of the Villarcayo Synclinorium show several localities, respectively. Geologically, it is situated in hundred meters of siliciclastic and carbonate materi- the northern limb of the Villarcayo Synclinorium, in als arranged in transgressive-regressive cycles (Floquet the northern part of the Basque-Cantabrian Region. 1991, 1998; Berreteaga 2008). Time-equivalent Actinopterygian remains have been found in a quarry materials in the Miranda-Treviño Synclinorium are near the village of Quintanilla la Ojada. also arranged in comparable transgressive-regressive Th e Villarcayo and Miranda-Treviño synclinoria cycles (Baceta 1996; Baceta et al. 1999). Th e Maas- belong to the southern part of the Basque-Cantabrian trichtian deposits of both synclinoria have yielded Basin (Fig. 1). During the Late Cretaceous and abundant actinopterygian remains. Early Paleogene, the sedimentation throughout the study area comprised varied depositional environ- FACIES DESCRIPTION ments ranging from inner self to coastal and even Th e lower part of the Quintanilla la Ojada section continental ones (Floquet 1991; Pluchery 1995). consists of bioclastic calcarenites that include: bivalves, In Campanian-Maastrichtian time interval the gastropods, brachiopods, green and red algae, sponges, regression trend in the Basque-Cantabrian Basin oysters, echinoderms, bryozoans, serpulids, foramini- resulted in the progradation of deltaic siliciclastic fers, ostracods, and crustaceans (Floquet 1991). Th ese systems and the development of shallow marine calcarenites correspond to the top of the Tubilla del environments, inhabited by a fauna rich in chon- Agua Formation, as defi ned by Floquet et al. (1982). GEODIVERSITAS • 2011 • 33 (2) 287 Berreteaga et al. Th is formation is dated from the fi nal Santonian to (Sobrepeña Formation, Floquet 1991; Berreteaga probably early Campanian by foraminifera and am- et al. 2008a) (Fig. 2). monites (Floquet 1991, 1998; Gräfe 2005). Th e Tubilla del Agua Formation shows a gradual FACIES INTERPRETATION facies-transition to the overlaying siliciclastic unit. Th e Th e Rioseco Member is interpreted as an easterly latter is nearly 60 m in thickness in the Quintanilla progradational deltaic system (Floquet 1991; Ber- la Ojada site; it consists of well-rounded conglomer- reteaga 2008). Th e boundary between the Rioseco ates and sandstones of mainly quartz composition