El 20 de diciembre próximo, cuando la localidad de Rincón de los Sauces, Neuquén, Argentina, cumpla su 45º Aniversario, conjuntamente con el 16º Aniversario del Museo Argentino Urquiza, se hará la presentación oficial de la réplica del dinosaurio carnívoro Viavenator exxoni, en el marco de la inauguración del edificio de la nueva Casa de la Cultura del Bicentenario.
Para el Museo y su equipo, este es un momento sumamente trascendente, ya que es la presentación de la primera réplica del esqueleto completo de un dinosaurio recuperado de la zona.
Este evento ocurrirá en horas de la tarde, previo al acto protocolar donde serán parte el Intendente Marcelo Rucci junto con el Gobernador Omar Gutierrez, además de otros funcionarios municipales y provinciales. A partir de las 19:00hs el dinosaurio quedará en la sala del nuevo edificio para que público pueda ingresar a conocerlo.

 
Concluye la campaña de extracción de un nuevo dinosaurio saurópodo en el norte de Neuquén, Argenitna. Esta nueva etapa en la recuperación de este enorme ejemplar, hallado en el 2012, ha terminado satisfactoriamente. A pesar de que no se ha podido recuperar la totalidad de los materiales, se cumplió con el objetivo principal, el de retomar los trabajos de extracción en el sitio. Los numerosos materiales detectados en el último día de trabajo, plantean la necesidad de continuar las actividades en el 2017. Sólo queda dar comienzo al lento trabajo de preparación en el laboratorio del Museo Municipal Argentino Urquiza, Rincón de los Sauces, donde ya reposan los nuevos restos.

 
 
La réplica del primer dinosaurio carnívoro, Viavenator exxoni, ya se encuentra depositada en las instalaciones del Museo Municipal Argentino Urquiza, Rincón de los Sauces, Neuquén, luego de su largo viaje desde la provincia de Buenos, Aires. Se trata de una réplica a tamaño natural del esqueleto de este nuevo abelisaurio, el cual fue dado a conocer a principios de este año. Para el MAU, es sumamente importante, ya que será la primera réplica de un dinosaurio de la colección que será montada en las instalaciones del Museo. Todo está previsto que la presentación oficial se lleve adelante el próximo 20 de diciembre, día donde se realizan no solo los festejos de aniversario de la localidad de Rincón de los Sauces, sino que además, el Museo cumple sus 16 años de vida. Una vez realizado esto, los visitantes podrán concurrir al mismo para apreciar a esta magnífica nueva pieza de la exhibición.

Filippi, L., Barrios, F. y Arcucci, A.
La Formación Bajo de la Carpa (Santoniano) de Norpatagonia es una unidad muy fosilífera, que ha brindado restos de peces, quelonios, serpientes, dinosaurios saurópodos, terópodos avianos y no-avianos, y principalmente cocodrilos. En la localidad de Cerro Overo, al sudoeste de Rincón de los Sauces, provincia del Neuquén, hasta el momento esta unidad solo brindó restos de Sauropoda (Overosaurus paradasorum Coria et al., 2013). En esta contribución se da a conocer el primer registro de un Crocodyliforme Mesoeucrocodylia proveniente de dicha localidad. El espécimen  corresponde a la mitad anterior de ambas ramas mandibulares articuladas, integradas cada una por los dentarios con algunos dientes preservados, y los espleniales. En base a comparaciones encontramos similitudes morfológicas con Peirosauridae: por la presencia de dientes zifodontes, sínfisis esplenial y foramen intermandibular oral próximo a la región sinfiseal, particularmente de mandíbula elongada antero-posteriormente, de forma espatulada en su extremo más anterior, comprimida dorso-ventralmente, y con contacto dentario-esplenial en la región sinfiseal en forma de cuña y extendido anteriormente. La morfología recuerda a Pepesuchus Campos et al., 2011, y principalmente a Itasuchus Price, 1955, que los diferencia de otros peirosáuridos (e.g. Gasparinisuchus Martinelli et al., 2012 y Montealtosuchus Carvalho et al., 2007), que presentan mandíbula más robusta con una región sinfiseal tan ancha como larga, y superficie dorsal cóncava. Sin embargo, la ausencia de alvéolos confluentes en el material de Cerro Overo sugiere que se trata de un nuevo taxón, lo que aumentaría la diversidad de Peirosauridae en el Cretácico de Patagonia.
11º Congreso de la Asociación Paleontológica Argentina, Gral. Roca, Río Negro, Argentina, 2016.

 
Filippi, L.,  Juárez Valieri, R., Gallina, P., Méndez, A., Gianechini, F. y Garrido, A.


Paleontological fieldworks carried out on upper section of the Bajo de la Carpa Formation (Santonian, Upper Cretaceous) at La Invernada area, near  Rincón de los Sauces city (northeast Neuquén Province), result in the discovery of several specimens of derived titanosaurs, belonging to multiple taxa. One of them, consists of an articulated modest-sized individual with a nearly complete skull, the axial sequence from the atlas to the last sacral vertebrae with their respective ribs, and both ilia.This sequence is composed by thirteen cervical, ten dorsal and six sacral vertebrae. The skull displays a spatulate snout morphology, with a straight anterior margin, similar to the morphology previously recognized in other titanosaurs such as Antarctosaurus, Bonitasaura and Brasilotitan. The neurocranial morphology is highly derived compared with other titanosaur taxa with well-known skulls such as Sarmientosaurus, Nemegtosaurus, Tapuiasaurus and Rapetosaurus, with displaced frontals located behind the orbits, resulting in an opposite position to the anterior margin of the snout. The occipital condyle is not preserved, but the location of the neurocranial elements and the atlas-axis complex (found in anatomical position) allow to infer a nearly perpendicular position for the tooth row respect to the cervical sequence. This particular condition, confirmed for first time in a derived titanosaur, is morphologically convergent with derived rebbachisaurids such as Nigersaurus. Besides, their respective biochrons are in agreement with the paleoecological niche replacement of the rebbachisaurids by the spatulate snouted titanosaurs in South America, as previously suggested in the post Turonian faunal turnover.
 
11º Congreso de la Asociación Argentina de Paleontología, Gral. Roca, Río Negro, Argentina 2016.
 
 

 
El equipo del Museo Argentino Urquiza (Rincón de los Sauces, Neuquén, Argentina)  realizó trabajos preliminares en el sitio de Cañadón Mistringa, para despejar varias toneladas de roca que cubrían un ejemplar de saurópodo parcialmente recuperado. Esta tarea, llevada adelante gracias al apoyo logístico del sector de Obras Públicas de la Municipalidad de Rincón de los Sauces, permitirá agilizar notablemente los trabajos de campo. Llega la época de campañas y la posibilidad de extraer definitivamente todo el material restante de este enorme dinosaurio.

A Jurassic pterosaur from Patagonia

 
 
Pterosaurs are an extinct group of highly modified flying reptiles that thrived during the Mesozoic. This group has unique and remarkable skeletal adaptations to powered flight, including pneumatic bones and an elongate digit IV supporting a wing-membrane. Two major body plans have traditionally been recognized: the primitive, primarily long-tailed paraphyletic “rhamphorhynchoids” (preferably currently recognized as non-pterodactyloids) and the derived short-tailed pterodactyloids. These two groups differ considerably in their general anatomy and also exhibit a remarkably different neuroanatomy and inferred head posture, which has been linked to different lifestyles and behaviours and improved flying capabilities in these reptiles. Pterosaur neuroanatomy, is known from just a few three-dimensionally preserved braincases of non-pterodactyloids (as Rhamphorhynchidae) and pterodactyloids, between which there is a large morphological gap. Here we report on a new Jurassic pterosaur from Argentina, Allkaruen koi gen. et sp. nov., remains of which include a superbly preserved, uncrushed braincase that sheds light on the origins of the highly derived neuroanatomy of pterodactyloids and their close relatives. A µCT ray-generated virtual endocast shows that the new pterosaur exhibits a mosaic of plesiomorphic and derived traits of the inner ear and neuroanatomy that fills an important gap between those of non-monofenestratan breviquartossans (Rhamphorhynchidae) and derived pterodactyloids. These results suggest that, while modularity may play an important role at one anatomical level, at a finer level the evolution of structures within a module may follow a mosaic pattern.
 
Codorniú L, Paulina Carabajal A, Pol D, Unwin D, Rauhut OWM. (2016) A Jurassic pterosaur from Patagonia and the origin of the pterodactyloid neurocranium. PeerJ 4:e2311

Nuevos hallazgos en La Invernada

 
 
El pasado fin de semana, el MAU, Museo Municipal Argentino Urquiza, Rincón de los Sauces, Neuquén, Argentina,  realizó la evaluación de una denuncia de hallazgo de restos fósiles en el área La Invernada. Después de transitar por un camino de muy dificil acceso, se pudo dar con el lugar exacto de donde provenian los restos recuperados. Los materiales entregados al Museo correspondían a tres de los cinco huesos metacarpianos de una pata delantera de un dinosaurio saurópodo. La evaluación realizada en el lugar permitió determinar que el resto de los huesos faltantes aún estaban in situ, los cuales se encontraban muy bien preservados y articulados con el resto de dicha pata. En futuras salidas, el resto de los huesos serán recuperados y se evaluará si puede que el resto del dinosaurio se encuentre bajo la roca.


Rodolfo A. Coria and Philip J. Currie

A skeleton discovered in the Upper Cretaceous Sierra Barrosa Formation (Turonian-Coniacian) of Neuquén Province, Argentina represents a new species of theropod dinosaur related to the long snouted, highly pneumatized Megaraptoridae. The holotype specimen of Murusraptor barrosaensis n.gen et n.sp. includes much of the skull, axial skeleton, pelvis and tibia. Murusraptor is unique in having several diagnostic features that include anterodorsal process of lacrimal longer than height of preorbital process, and a thick, shelf-like thickening on the lateral surface of surangular ventral to the groove between the anterior surangular foramen and the insert for the uppermost intramandibular process of the dentary. Other characteristic features of Murusraptor barrosaensis n.gen. et n. sp. include a large mandibular fenestra, distal ends of caudal neural spines laterally thickened into lateral knob-like processes, short ischia distally flattened and slightly expanded dorsoventrally. Murusraptor belongs to a Patagonian radiation of megaraptorids together with Aerosteon, Megaraptor and Orkoraptor. In spite being immature, it is a larger but more gracile animal than existing specimens of Megaraptor, and is comparable in size with Aerosteon and Orkoraptor. The controversial phylogeny of the Megaraptoridae as members of the Allosauroidea or a clade of Coelurosauria is considered analyzing two alternative data sets.

Coria RA, Currie PJ (2016) A New Megaraptoran Dinosaur (Dinosauria, Theropoda, Megaraptoridae) from the Late Cretaceous of Patagonia. PLoS ONE 11(7): e0157973. doi:10.1371/ journal.pone.0157973


Sebastián Apesteguía, Nathan D. Smith, Rubén Juárez Valieri, Peter J. Makovicky

Late Cretaceous terrestrial strata of the Neuquén Basin, northern Patagonia, Argentina have yielded a rich fauna of dinosaurs and other vertebrates. The diversity of saurischian dinosaurs is particularly high, especially in the late Cenomanian-early Turonian Huincul Formation, which has yielded specimens of rebacchisaurid and titanosaurian sauropods, and abelisaurid and carcharodontosaurid theropods. Continued sampling is adding to the known vertebrate diversity of this unit.

A new, partially articulated mid-sized theropod was found in rocks from the Huincul Formation. It exhibits a unique combination of traits that distinguish it from other known theropods justifying erection of a new taxon, Gualicho shinyae gen. et sp. nov. Gualicho possesses a didactyl manus with the third digit reduced to a metacarpal splint reminiscent of tyrannosaurids, but both phylogenetic and multivariate analyses indicate that didactyly is convergent in these groups. Derived characters of the scapula, femur, and fibula supports the new theropod as the sister taxon of the nearly coeval African theropod Deltadromeus and as a neovenatorid carcharodontosaurian. A number of these features are independently present in ceratosaurs, and Gualicho exhibits an unusual mosaic of ceratosaurian and tetanuran synapomorphies distributed throughout the skeleton.

Apesteguía S, Smith ND, Juárez Valieri R, Makovicky PJ (2016) An Unusual New Theropod with a Didactyl Manus from the Upper Cretaceous of Patagonia, Argentina. PLoS ONE 11(7): e0157793. doi:10.1371/journal.pone.0157793


Durante la semana pasada el equipo del MAU, Museo Municipal Argentino Urquiza de Rincón de los Sauces, Neuquén, realizó el inesperado hallazgo de los restos de un ejemplar de dinosaurio ornitópodo, el cual se encuentra en muy buen estado de preservación. Las tareas de campo permitieron recuperar los restos integrados por la porción anterior del cuerpo del animal, integrada por las últimas cervicales y las primeras siete dorsales, articuladas con sus correspondientes costillas y ambas escapulo-coracoides. Además, excepcionalmente se halló el miembro anterior derecho completo y articulado al cuerpo. Si bien se habían hallado restos en la zona de este grupo de dinosaurios ornitisquios, este es el primer ejemplar de relevancia hallado en la zona norte de la Provincia de Neuquén, por lo que permite engrosar el conocimiento de la fauna de dinosaurios de esta región. Actualmente el material esta siendo preparado en el laboratorio del Museo.

 
Penélope Cruzado-Caballeroa, Leonardo S. Filippi, Ariel H. Méndez, Alberto C. Garrido and Rubén D. Juárez Valieri

Ornithopods are the least known dinosaurs within the Upper Cretaceous record of Argentina. For this rea-son every new record is very important to know their evolution in South America. Here, we describe a new remain of an indeterminate ornithopod recovered in the Petrobrasaurus quarry of the Puesto Hernández area, northeastern Neuquén province (Argentina), late Coniacian–early Santonian in age. MAU-Pv-PH-458 is the northernmost bone record of an ornithopod in Argentina. This is a fragmentary neural arch fromthe middle section of the dorsal series of similar size to Macrogryphosaurus gondwanicus. MAU-Pv-PH-458 has typical ornithopod characters such as a lateromedial narrow neural spine and transverse processes dorsoposteriorly to posteriorly oriented. It shares with Macrogryphosaurus the presence of a deep cannel between the bases of the postzygapophysis, which is a continuation of the channel that separates the postzygapophyses in posterior view. MAU-Pv-PH-458 increases the ornithopod record from the Plottier Formation.

Cruzado-Caballero, P., et al., New record of ornithopod dinosaur from the Plottier Formation (Upper Cretaceous), Patagonia, Argentina. Annales de Paléontologie (2016), http://dx.doi.org/10.1016/j.annpal.2016.02.003


Ariana Paulina Carabajal, Juan I. Canale, and Alejandro Haluza

Report a new rebbachisaurid material recovered from the Candeleros Formation (Cenomanian) of northwest Patagonia, Argentina. The cranial remains consist of a partial braincase and a right quadrate. Fractures in the braincase exposed the endocranial cavity, allowing the first study of the brain and inner ear morphologies of a South American rebbachisaurid. The braincase and cranial endocast both exhibit traits similar to those observed in the Cretaceous rebbachisaurs Nigersaurus from Africa and Limaysaurus from Argentina, although in terms of osteology, the South American taxa are highly similar. The endocast is more similar to that of Nigersaurus than to those of Diplodocus and Camarasaurus, suggesting some probable rebbachisaurid features such as the noteworthy presence of the flocculus. The overall morphology of the quadrate shows similarities with Limaysaurus and Nigersaurus. However, differences such as the broader posterior fossa and the shape and orientation of the head and the pterygoid process indicate that the new specimen could represent a distinct taxon.

Ariana Paulina Carabajal, Juan I. Canale & Alejandro Haluza (2016): New rebbachisaurid cranial remains (Sauropoda, Diplodocoidea) from the Cretaceous of Patagonia, Argentina, and the first endocranial description for a South American representative of the clade, Journal of Vertebrate Paleontology, DOI: 10.1080/02724634.2016.1167067


Jeffrey A. Wilson, Diego Pol, Alberto B. Carvalho & Hussam Zaher

Although Titanosauria is the most diverse and late-surviving sauropod lineage, cranial elements are known for just over 24 of its 70+ genera – the vast majority of which are fairly fragmentary and restricted to the Late Cretaceous. Only three complete titanosaur skulls have been described to date; two of these are from the latest Cretaceous (Nemegtosaurus, Rapetosaurus), and the third, Tapuiasaurus, is from the Early Cretaceous (Aptian). In this contribution, we build on the initial treatment of the taxon by providing a complete description of the cranial elements that benefits from additional preparation and computed tomography imaging. We identify six additional features diagnosing Tapuiasaurus macedoi, including a jugal with an elongate lacrimal process forming much of the posteroventral border of the antorbital fenestra, a lateral temporal fenestra divided by a second squamosal–postorbital contact, and upper jaw teeth with labial wear facets. We directed the new morphological data in Tapuiasaurus as well as other observations towards a re-analysis of its phylogenetic position within Titanosauria. Our analysis yielded 34 most parsimonious trees, most of which recovered Tapuiasaurus in a basal position adjacent to the Early Cretaceous taxa Malawisaurus and Tangvayosaurus, but two trees recovered it within Late Cretaceous nemegtosaurids. We explored the effects of missing data and missing stratigraphic ranges on our results, concluding that (1) when missing data levels are high, resolution of even small amounts of that missing data can have dramatic effects on topology, (2) taxa that are mostly scored for characters that cannot be scored in other taxa may be topologically unstable and (3) there were several suboptimal trees that had greatly improved stratigraphic fit with relatively little compromise in terms of tree length.

Jeffrey A. Wilson, Diego Pol, Alberto B. Carvalho  and Hussam Zaher (2016) The skull of the titanosaur Tapuiasaurus macedoi (Dinosauria: Sauropoda), a basal titanosaur from the Lower Cretaceous of Brazil. Zoological Journal of the Linnean Society DOI: 10.1111/zoj.12420

 
 

Rubén D. F. Martínez, Matthew C. Lamanna, Fernando E. Novas, Ryan C. Ridgely, Gabriel A. Casal, Javier E. Martínez, Javier R. Vita & Lawrence M. Witmer

We describe Sarmientosaurus musacchioi gen. et sp. nov., a titanosaurian sauropod dinosaur from the Upper Cretaceous (Cenomanian - Turonian) Lower Member of the Bajo Barreal Formation of southern Chubut Province in central Patagonia, Argentina. The holotypic and only known specimen consists of an articulated, virtually complete skull and part of the cranial and middle cervical series. Sarmientosaurus exhibits the following distinctive features that we interpret as autapomorphies: (1) maximum diameter of orbit nearly 40% rostrocaudal length of cranium; (2) complex maxilla-lacrimal articulation, in which the lacrimal clasps the ascending ramus of the maxilla; (3) medial edge of caudal sector of maxillary ascending ramus bordering bony nasal aperture with low but distinct ridge; (4) ‘tongue-like’ ventral process of quadratojugal that overlaps quadrate caudally; (5) separate foramina for all three branches of the trigeminal nerve; (6) absence of median venous canal connecting infundibular region to ventral part of brainstem; (7) subvertical premaxillary, procumbent maxillary, and recumbent dentary teeth; (8) cervical vertebrae with ‘strut-like’ centroprezygapophyseal laminae; (9) extremely elongate and slender ossified tendon positioned ventrolateral to cervical vertebrae and ribs. The cranial endocast of Sarmientosaurus preserves some of the most complete information obtained to date regarding the brain and sensory systems of sauropods. Phylogenetic analysis recovers the new taxon as a basal member of Lithostrotia, as the most plesiomorphic titanosaurian to be preserved with a complete skull. Sarmientosaurus provides a wealth of new cranial evidence that reaffirms the close relationship of titanosaurs to Brachiosauridae. Moreover, the presence of the relatively derived lithostrotian Tapuiasaurus in Aptian deposits indicates that the new Patagonian genus represents a ‘ghost lineage’ with a comparatively plesiomorphic craniodental form, the evolutionary history of which is missing for at least 13 million years of the Cretaceous. The skull anatomy of Sarmientosaurus suggests that multiple titanosaurian species with dissimilar cranial structures coexisted in the early Late Cretaceous of southern South America. Furthermore, the new taxon possesses a number of distinctive morphologies such as the ossified cervical tendon, extremely pneumatized cervical vertebrae, and a habitually downward facing snout that have rarely, if ever, been documented in other titanosaurs, thus broadening our understanding of the anatomical diversity of this remarkable sauropod clade. The latter two features were convergently acquired by at least one penecontemporaneous diplodocoid, and may represent mutual specializations for consuming low-growing vegetation.

Martínez RDF, Lamanna MC, Novas FE, Ridgely RC, Casal GA, Martínez JE, et al. (2016) A Basal Lithostrotian Titanosaur (Dinosauria: Sauropoda) with a Complete Skull: Implications for the Evolution and Paleobiology of Titanosauria. PloS ONE 11(4): e0151661. doi:10.1371/journal. pone.0151661



Ricardo N. Martínez, Cecilia Apaldetti, Gustavo A. Correa, And Diego Abelín

The early evolution of Ornithodira the clade including pterosaurs and dinosaurs is poorly known. Until a decade ago, the basal radiation of Dinosauromorpha, the clade including dinosaurs and birds, was poorly understood because of the poor fossil record restricted to specimens known from the Ladinian Chañares Formation in Argentina. Over the last years the discovery of several non-dinosaurian dinosauromorphs dramatically expanded this record and also demonstrated that this group –previously restricted to de Middle Triassic survived at least well into the Norian. Although Norian non-dinosaurian dinosauromorphs have been reported from several regions around the world, the only known Norian non-dinosauriform dinosauromorphs Dromomeron romeri Irmis, Nesbitt, Padian, Smith, Turner, Woody, and Downs and Dromomeron gregorii Nesbitt, Irmis, Parker, Smith, Turner, and Rowe come from North America. We report here the first record from the Southern Hemisphere of a non-dinosauriform dinosauromorph, Dromomeron gigas sp. nov., from the Norian Quebrada del Barro Formation, northwestern Argentina. A phylogenetic analysis recovers Dromomeron gigas nested into the monophyletic group Lagerpetidae, and as the sister taxon to Dromomeron romeri. The inclusion of D. gigas within Lagerpetidae suggests that body size increased in this lineage over time, as was previously demonstrated for Dinosauriformes as a whole, and that lagerpetids reached a larger size than previously thought. Finally, the new finding provides new information on the basal radiation of Dinosauromorpha constituting the first record of a Norian association of dinosaurs with non-dinosauriform dinosauromorphs outside North America.

Ricardo N. Martínez, Cecilia Apaldetti, Gustavo A. Correa, Diego Abelín (2016). A Norian lagerpetid dinosauromorph from the Quebrada del Barro Formation, northwestern Argentina. Ameghiniana 53: 1–13.


Federico Brissón Egli, Federico L. Agnolín, And Fernando Novas

Abelisauroids are the most abundant theropods in the Cretaceous beds of Patagonia. They are traditionally subdivided into large-sized Abelisauridae and smaller Noasauridae. Here, we describe a new specimen of the small enigmatic abelisauroid Velocisaurus unicus Bonaparte, 1991, which was previously known from a single incomplete specimen from Neuquén City, Neuquén Province, Patagonia. The new material comes from the Santonian Bajo de la Carpa Formation (Late Cretaceous) at the Paso Córdoba locality, Río Negro Province. It comprises an almost complete left hind limb and offers novel information about the anatomy of this poorly known abelisauroid. The new material shows that Velocisaurus is remarkable in having a very short, stout, and anteriorly bowed femur, which has a notably subtriangular cross-section at its proximal end. The tibia is long and slender, and the anterior surface of the distal end is anteroposteriorly flat and transversely expanded, with an enlarged surface for the ascending process of the astragalus. The pes has a stout third metatarsal, rod-like metatarsals II and IV, and highly modified phalanges of digit IV. The unique combination of characters of Velocisaurus indicates that this taxon belongs to a still poorly understood radiation of gracile-limbed abelisauroids. The inclusion of Velocisaurus in a comprehensive phylogenetic analysis recovers a monophyletic Noasauridae, but with only very weak support. Detailed analysis of features supporting the inclusion of Velocisaurus within Noasauridae is discussed, and their implications for abelisauroid phylogeny are revisited.
Federico Brissón Egli, Federico L. Agnolín & Fernando Novas 2016. A new specimen of Velocisaurus unicus (Theropoda, Abelisauroidea) from the Paso Córdoba locality (Santonian), Río Negro, Argentina, Journal of Vertebrate Paleontology, DOI: 10.1080/02724634.2016.111915


En el día de ayer, se llevó adelante la presentación formal del nuevo dinosaurio del MAU, Museo Municipal Argentino Urquiza, Rincón de los Sauces, Neuquén: Viavenator exxoni, un nuevo género y especie de abelisaurio que aporta información relevante que permite avanzar en el conocimiento de este grupo de terópodos.
Este ejemplar, corresponde al primer dinosaurio carnívoro de la colección del MAU, por lo que todo el equipo del trabajo del museo y los colegas que han participado de su estudio, se encuentran muy satisfechos. Si bien el potencial del área La Invernada, en el cual se viene trabajando desde hace un poco más de tres años, es inmenso, la publicación de este dinosaurio, representa el primero de una serie de otros ejemplares que han sido recuperados allí, entre los que se mencionan, varios dinosaurios titanosaurios, una descena de ejemplares de tortugas y peces.
Los huesos orginales de Viavenator se encontrarán temporalmente exhibidos al público en el laboratorio del Museo hasta fines de Marzo.


E. Martin Hechenleitner, Lucas E. Fiorelli, Gerald Grellettinner,  Léa Leuzinger, Giorgio Basilici, Jeremías R. A. Taborda, Sergio R. De La Vega And Carlos A. Bustamante

            Cretaceous titanosaur nesting sites are currently known only from Europe, Asia and South America. In the latter, only the Auca Mahuevo and Sanagasta nesting sites have been confidently assigned to this clade of sauropod dinosaurs. Here we report the discovery of the first eggs and egg clutches found at Tama, a new Upper Cretaceous fossiliferous locality in the Los Llanos Formation, Sierra de Los Llanos (La Rioja, NW Argentina). At least five egg clutches, several partially preserved, isolated eggs and many eggshell fragments were discovered in a single outcrop of a sandstone horizon which represents a cumulative palaeosol profile. Although the mechanical and digital preparation of eggs did not reveal any embryonic remains in ovo, the morphology of the eggs and eggshells closely matches that of titanosaur eggs and eggshells found worldwide. The morphology and spatial grouping of the titanosaur eggs from Tama, along with geological observations support a burrow-nesting strategy for these dinosaurs. Although the Sanagasta and Tama eggs were found in the same stratigraphical unit and share several morphological characters, they clearly differ in shell thickness and egg size. This, coupled with the interpretation of different sedimentary contexts for these nesting sites, strongly suggests that at least two different titanosaur species nested in La Rioja during the Late Cretaceous, using different nesting strategies. The occurrence of this new titanosaur nesting site in a semiarid palaeoenvironment represents an interesting case study for the reproductive biology of the titanosaur dinosaurs, particularly their labile nesting behaviour.

Hechenleitner, EM, Fiorelli, LE, Grellettinner, G,  Leuzinger, L, Basilici, G, Taborda, JRA,  De La Vega, SR And Bustamante, CA. 2016. A new Upper Cretaceous Titanosaur nesting site from La Rioja (Nw Argentina), with implications for Titanosaur nesting strategies. Palaeontology, pp. 1–14.

 
 

Juan Marcos Jannello, Ignacio A. Cerda, Marcelo S. de la Fuente

            Yaminuechelys is a long-necked chelid turtle whose remains have been recovered from outcrops of the Santonian- Maastrichtian and Danian of SouthAmerica.With the purpose of providing data about shell sculpturing origin and palaeoecology, the bone histology of several shell elements (including neural, costal, peripheral and plastral plates) of Yaminuechelys is described herein. Histological analysis reveals that Yaminuechelys shares with Chelidae the presence of interwoven structural fibre bundles in the external cortex, and parallel-fibred bone of the internal cortex. The presence of resorption lines in several samples indicates that the particular ornamentation of the external surfaces originated, at least in part, by focalized resorption and new bone deposition. This mechanism for ornamentation origin and maintenance is here described for the first time in a turtle. Compactness of the shell bones is consistent with an aquatic habitat, which supports previous hypothesis based on palaeoenvironmental and morphological data.

Janello, JM, Cerda, IA & de la Fuente, MS. 2016. Shell bone histology of the long-necked chelid Yaminuechelys (Testudines: Pleurodira) from the late Cretaceous—early Palaeocene of Patagonia with comments on the histogenesis of bone ornamentation. Sci Nat. 103:26.DOI 10.1007/s00114-016-1346-3.


Francisco Barrios, Ariana Paulina-Carabajal y Paula Bona

Peirosaurids are a group of Cretaceous continental crocodyliforms from Gondwana. Two species are known from the Neuquén Group in Argentina: Lomasuchus palpebrosus (Portezuelo Formation, late Turonian–early Coniacian) and Gasparinisuchus peirosauroides (Bajo de la Carpa and Anacleto formations, Santonian and early Campanian, respectively). Here, we describe the first peirosaurid from the Cerro Lisandro Formation, Bayomesasuchus hernandezi gen. et sp. nov. The material corresponds to a fragmentary skull and mandible. Although fragmentary, this is the most complete crocodyliform specimen recorded for the Cerro Lisandro Formation. In a phylogenetic analysis Bayomesasuchus is depicted in a polytomy together with South American peirosaurids and the African form Hamadasuchus rebouli.

Barrios, F. Paulina-Carabajal, A, y Bona Paula. 2016. A new Peirosaurid (Crocodyliformes, Mesoeucrocodylia) from the Upper Cretaceous of Patagonia, Argentina. Ameghiniana 53 (1):14-25.

 
El Museo Municipal Argentino Urquiza ya tiene su primer dinosaurio terópodo
Ya se encuentra publicado en versión online el trabajo sobre este dinosaurio carnívoro, un nuevo abelisaurio, que proviene de La Invernada (Neuquén, Argentina) de rocas de la Formación Bajo de la Carpa. La excelente preservación y la significativa información que aportó el ejemplar resultaron relevantes para avanzar en el conocimiento de este grupo de terópodos, los abelisaurios. Viavenator ("cazador del camino") exxoni gen. et sp. nov. es el primero dado a conocer de una serie de ejemplares que han sido recuperados en la zona de La Invernada gracias al enorme apoyo de la empresa Exxonmobil.
Filippi, LS, Méndez, AH, Juárez Valieri, R. & Garrido, AC. 2016. A new brachyrostran with hypertrophied axial structures reveals an unexpected radiation of latest Cretaceous abelisaurids. Creataceous Research 61:209-219.


Bernardo J. González Riga, Matthew C. Lamanna, Leonardo D. Ortiz David,
Jorge O. Calvo & Juan P. Coria

Titanosauria is an exceptionally diverse, globally-distributed clade of sauropod dinosaurs that includes the largest known land animals. Knowledge of titanosaurian pedal structure is critical to understanding the stance and locomotion of these enormous herbivores and, by extension, gigantic terrestrial vertebrates as a whole. However, completely preserved pedes are extremely rare among Titanosauria, especially as regards the truly giant members of the group. Here we describe Notocolossus gonzalezparejasi gen. et sp. nov. from the Upper Cretaceous of Mendoza Province, Argentina. With a powerfully-constructed humerus 1.76 m in length, Notocolossus is one of the largest known dinosaurs. Furthermore, the complete pes of the new taxon exhibits a strikingly compact, homogeneous metatarsus—seemingly adapted for bearing extraordinary weight—and truncated unguals, morphologies that are otherwise unknown in Sauropoda. The pes underwent a near-progressive reduction in the number of phalanges along the line to derived titanosaurs, eventually resulting in the reduced hind foot of these sauropods.

González Riga, BJ., Lamanna, MC., Ortiz David, LD., Calvo, JO. & Coria, JP. 2016 A gigantic new dinosaur from Argentina and the evolution of the sauropod hind foot. Nature. Scientific Reports. DOI: 10.1038/srep19165


 
 
Continúan las tareas de preparación de fósiles en el MAU

Quienes visitan en estas vacaciones de verano el Museo Municipal Argentino Urquiza, Rincón de los Sauces, Neuquén, tienen la posibilidad de observar muy de cerca como se estan preparando los materiales recuperados en la última campaña paleontológica. Se trata de un ejemplar de dinosaurio Titanosaurio, conocido comunmente como "cuello largo", el cual se encontraba completo y articulado desde el cráneo hasta la cadera. Tanto la cola como las extremidades no fueron halladas en el sitio. Se espera que a finales de este año el ejemplar este completamente limpio para dar inicio a su estudio.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 



Filippi, L. S, Martinelli, A & Garrido, A. C.

In this contribution, a fossil tooth assemblage from the Bajo de la Carpa Formation (Santonian, Upper Cretaceous) in a different paleoenvironmental context from that recorded at the Neuquén city and Paso Córdova localities (Patagonia, Argentina), is here presented. It includes isolated teeth of Dipnoi, represented by the species Ceratodus kaopen and Atlantoceratodus patagonicus; mesoeucrocodylian isolated teeth referred to Peirosauridae; and isolated teeth of Abelisauridae theropods and Titanosauria sauropods. The Mesoeucrocodylia, Abelisauridae and Titanosauria taxa are consistent with the fossil record of the region, represented by the Coloradoan tetrapod assemblage of Santonian to early Campanian age. However, the lungfish A. patagonicus represents the first occurrence for the Bajo de la Carpa Formation, being this record the oldest one for this taxón.

Filippi, L.S, Martinelli, A.G. y Garrido, A.C. 2015. Una nueva asociación de dientes vertebrados para la Formación Bajo de la Carpa (Santoniense, Cretácico Superior) en Rincón de los Sauces, Neuquén, Argentina. Revista Española de Paleontología 30 (2): 223-238.



 

 
 
 
 
 
 
 
 
 
 
 


Lucas E. Fiorelli, Juan M. Leardi, E. Martín Hechenleitner, Diego Pol, Giorgio Basilici & Gerald Grellet-Tinner.

The Cretaceous witnessed the greatest diversity of Gondwanan notosuchian crocodyliforms, which displayed high levels of diversity and a notable array of specialized forms that developed in different ecological niches. Among this diversity, the advanced notosuchians are a clade of mid body sized forms which displays a remarkable abundance but is restricted to two lithological units from the Late Cretaceous of South America, the Adamantina Formation in southeastern Brazil and the Bajo de la Carpa Formation in Patagonia (Argentina). The only exceptions known so far were the Late Cretaceous Labidiosuchus from the Marilia Formation in Brazil and Yacarerani from the Cajones Formation in Bolivia. Herein we report a new Cretaceous crocodyliform, Llanosuchus tamaensis gen. nov. et sp. nov., found in the Los Llanos Formation (Campanian?) in northwestern Argentina (La Rioja Province). The small specimen includes well preserved fragments of the cranium and mandible with an estimated skull size of about 9 cm lengths. This crocodyliform shares several derived characters with Notosuchus terrestris from the Bajo de la Carpa Formation (Patagonia) and it was found in a weakly developed sandy paleosol profile formed in wet local conditions but in a region characterized by semi-arid climate and active eolian sedimentation. The presence of a new advanced notosuchian in the Cretaceous of western Gondwana, and its intermediate geographical region between the known South American species (Brazil, Argentina and Bolivia), has interesting implications, and adds another record of an advanced notosuchian in deposits with inferred warm climates and semi-arid paleoenvironments. Finally, Llanosuchus tamaensis supports a Late Cretaceous age for Los Llanos Formation with important geological implications for La Rioja Province.

L. E. Fiorelli, J. M. Leardi, E. M. Hechenleitner, D. Pol, G. Basilici & G. Grellet-Tinner 2016. A new Late Cretaceous crocodyliform from the western margin of Gondwana (La Rioja Province, Argentina). Cretaceous Research 60: 194-209.

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