The postcranial anatomy of Coloradisaurus brevis (Dinosauria: Sauropodomorpha) from the Late Triassic of Argentina and its phylogenetic implications

Basal sauropodomorphs from the Upper Triassic Los Colorados Formation of northwestern Argentina have been known for several decades but most of them are only briefly described. New postrcanial remains of Coloradisaurus brevis, the most gracile sauropodomorph from this unit, are described here and evaluated within a phylogenetic context. These materials belong to a single individual and include elements of the vertebral column, pectoral girdle, incomplete forelimb, pelvis, and hindlimb. These elements share autapomorphic features with the type specimen of Coloradisaurus brevis, and provide novel and unique features that diagnose this taxon, such as pubic apron with semicircular cross section and with a depression on its anterior surface, distal surface of the tibia deflected and facing posterodistally, and well-developed pyramidal dorsal process of the posteromedial corner of the astragalus. Several postcranial characters of Coloradisaurus are exclusively shared with Lufengosaurus, from the Lower Jurassic of China. The inclusion of this information in two recent phylogenetic datasets depicts Coloradisaurus as closely related to Lufengosaurus and well nested within Plateosauria. Both datasets used indicate strong character support for the inclusion of Coloradisaurus and Lufengosaurus within Massospondylidae.Fil: Apaldetti, Graciela Cecilia. Universidad Nacional de San Juan. Museo de Ciencias Naturales; ArgentinaFil: Pol, Diego. Museo Paleontológico Egidio Feruglio; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: Yates, Adam. University of the Witwatersrand, Bernard Price Institute for Palaeontological Research; Sudáfric

New information on the skull of Coloradisaurus brevis Bonaparte (Dinosauria, Sauropodomorpha) from the upper Los Colorados Formation (Late Triassic), northwestern Argentina

Coloradisaurus brevis Bonaparte is a basal sauropodomorph from the upper Los Colorados Formation (Late Triassic), La Rioja Province, Argentina. Although it is frequently used in phylogenetic analyses, its position within basal Sauropodomorpha remains uncertain. Several characters of Coloradisaurus are shared with Massospondylidae: posterolateral process of the premaxilla and the anteroventral process of the nasal separated by the maxilla, dorsal margin of the postorbital with a distinct embayment between anterior and posterior processes, dorsoventral depth of the parasphenoid rostrum about equal to its transverse width, and four premaxillary teeth. Coloradisaurus shares with Plateosauridae and Riojasaurus Bonaparte a well developed external narial fossa, ascending ramus of the maxilla tapering dorsally, subtriangular antorbital fossa with a straight posterior margin, jugal ramus of the quadratojugal no longer than the squamosal ramus, basipterygoid processes and the parasphenoid rostrum below the level of basioccipital condyle and basal tuberae, and serrations along most length of both carinae. Here we present new information on the skull of the type specimen of Coloradisaurus, which can be diagnosed by the following unique combination of characters: anteroposteriorly short posterior process of the prefrontal; antorbital fossa of the lachrymal restricted to its ventral third; jugal contributing to the antorbital fenestra; pterygoid wing of the quadrate occupying less than 70% of its total height; paraoccipital processes horizontally directed; anterior end of the dentary ventrally curved; strong medial embayment behind glenoid of the articular; maxillary and dentary tooth crowns lanceolate and distally recurved with nearly flat lingual surface; and all teeth with approximately equal height. The new information was tested through a phylogenetic analysis that enforces the position of Coloradisaurus in a monophyletic clade Massospondylidae, as the sister-taxon to Lufengosaurus + Glacialisaurus. This result evidences the widespread radiation of massospondylids and the restricted distribution and abundance of plateosaurids in southwestern Pangea during Late Triassic-Early Jurassic.Sesiones libresFacultad de Ciencias Naturales y Muse

A new sphenodontian (Lepidosauria: Rhynchocephalia) from the Late Triassic of Argentina and the early origin of the herbivore opisthodontians

Sphenodontians were a successful group of rhynchocephalian reptiles that dominated the fossil record of Lepidosauria during the Triassic and Jurassic. Although evidence of extinction is seen at the end of the Laurasian Early Cretaceous, they appeared to remain numerically abundant in South America until the end of the period. Most of the known Late Cretaceous record in South America is composed of opisthodontians, the herbivorous branch of Sphenodontia, whose oldest members were until recently reported to be from the Kimmeridgian?Tithonian (Late Jurassic). Here, we report a new sphenodontian, Sphenotitan leyesi gen. et sp. nov., collected from the Upper Triassic Quebrada del Barro Formation of northwestern Argentina. Phylogenetic analysis identifies Sphenotitan as a basal member of Opisthodontia, extending the known record of opisthodontians and the origin of herbivory in this group by 50 Myr.Fil: Martínez, Ricardo. Universidad Nacional de San Juan. Facultad de Cs.exactas Fisicas y Naturales. Instituto y Museo de Cs.naturales. Area de Paleontologia de Vertebrados; ArgentinaFil: Apaldetti, Graciela Cecilia. Universidad Nacional de San Juan. Facultad de Cs.exactas Fisicas y Naturales. Instituto y Museo de Cs.naturales. Area de Paleontologia de Vertebrados; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Colombi, Carina Ester. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Fisicas y Naturales. Instituto y Museo de Ciencias Naturales; ArgentinaFil: Praderio, Angel. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Fisicas y Naturales. Instituto y Museo de Ciencias Naturales; ArgentinaFil: Fernández, Eliana. Universidad Nacional de San Juan. Facultad de Cs.exactas Fisicas y Naturales. Instituto y Museo de Cs.naturales. Area de Paleontologia de Vertebrados; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Santi Malnis, Paula. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Fisicas y Naturales. Instituto y Museo de Ciencias Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Correa, Gustavo Alejandro. Universidad Nacional de San Juan. Facultad de Cs.exactas Fisicas y Naturales. Instituto y Museo de Cs.naturales. Area de Paleontologia de Vertebrados; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Abelin, Diego. Universidad Nacional de San Juan. Facultad de Cs.exactas Fisicas y Naturales. Instituto y Museo de Cs.naturales. Area de Paleontologia de Vertebrados; ArgentinaFil: Alcober, Oscar. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Fisicas y Naturales. Instituto y Museo de Ciencias Naturales; Argentin

New non-mammaliaform cynodont from the upper triassic Los Colorados formation, Ischigualasto-Villa Union basin (La Rioja, Argentina)

We report a new species of a small probainognathian cynodont found in the uppermost third of the Los Colorados Formation at the Parque Nacional Talampaya (La Rioja, Argentina). It is represented by a partial cranium with articulated lower jaw. The specimen, PULR-V121, housed at the Universidad Nacional de La Rioja, was analyzed through X-ray micro-tomography in yPF Tecnología S.A. (y-TEC, Ensenada, Buenos Aires, Argentina) using the Bruker SkyScan 1173 instrument. Although the results were acceptable, the resolution was not ideal due to the presence of ferruginous material in the sample. To overcome this issue, we performed a neutron tomography with the highest possible spatial resolution at the ANTARES instrument in the Forschungs-Neutronenquelle Heinz Maier-Leibnitz zentrum (FRM II, Garching, Germany). The new species is a tritheledontid with a unique character state combination. PULR-V121 has a large upper canine in conjunction with a reduced lower one, which is only shared with Riograndia among probainognathian cynodonts and with the mammaliaform Morganucodon. It bears a semicircular, very well-developed, ventrally projected angular process dissimilar from that in other non-mammaliaform cynodonts. It shares with other tritheledontids the presence of upper postcanines with a symmetrical main cusp with convex mesial and distal margins flanked by smaller, lingually placed accessory cusps; lower postcanines with a large, asymmetrical, mesial main cusp followed by smaller distal accessory cusps; and a ventrally bowed secondary osseous palate that reaches posteriorly up to the level of the tips of the upper postcanines and forms deep, narrow, lateral grooves for the lower postcanines. It is unique among prozostrodontians in the presence of a short osseous secondary palate that ends well-anteriorly to the anterior margin of the orbit, not reaching the end of the upper tooth row. Unlike Pachygenelinae, the upper postcanines lack cingula and their major axis is parallel to the tooth row. PULR-V121 is reconstructed as bearing 12 or 13 upper postcanines, a similar number to that observed in Elliotherium (13) and Chaliminia (13), a diagnostic feature of Chalimininae. A reduced number of lower postcanines (seven), regarding the number of upper ones, is a distinctive feature of PULR-V121, in which the last six upper postcanines lack a lower counter-element. PULR- V121 further differs from Chaliminia in having a notably shorter lower tooth row with the ascending process of the dentary well-posterior to the last lower postcanine and the masseteric fossa not reaching the level of the last lower postcanine. PULR-V121 lacks the strong osseous platform in the dentary, lateral to the last lower postcanines, which produces a strong lateral ridge present in the holotype of Chaliminia. The small non-procumbent posterior and the also small anterior (interpreted as i1) lower incisors preserved in PULR-V121 contrast with the relatively large, procumbent lower incisors observed in Chaliminia. PULR-V121 represents a new species that constitutes the second cynodont taxon recognized and the sixth reported cynodont specimen from the Upper Triassic Los Colorados Formation, adding to the diversity and knowledge of Norian South American probainognathians.Fil: Gaetano, Leandro Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; ArgentinaFil: Abdala, Fernando. Fundación Miguel Lillo. Dirección de Geología. Instituto de Palentologia; ArgentinaFil: Tartaglione, Aureliano. Technische Universität Lichtenbergstr; AlemaniaFil: Schultz, Michael. Technische Universität Lichtenbergstr; AlemaniaFil: Martinelli, Agustín Guillermo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Otero, Alejandro. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Paleontología Vertebrados; ArgentinaFil: Leardi, Juan Martín. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; ArgentinaFil: Apaldetti, Cecilia. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Físicas y Naturales; ArgentinaFil: Krapovickas, Verónica. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; ArgentinaXII Congreso de la Asociación Paleontológica ArgentinaBuenos AiresArgentinaAsociación Paleontológica Argentin

RELIGIOUS FREEDOM IN INDONESIA: Curious Cases of Dialogues, Fatwas and Laws

Sauropod dinosaurs include the largest terrestrial animals and are considered to have uninterrupted rapid rates of growth, which differs from their more basal relatives, which have a slower cyclical growth. Here we examine the bone microstructure of several sauropodo- morph dinosaurs, including basal taxa, as well as the more derived sauropods. Although our results agree that the plesiomorphic condition for Sauropodomorpha is cyclical growth dynamics, we found that the hypothesized dichotomy between the growth patterns of basal and more derived sauropodomorphs is not supported. Here, we show that sauropod-like growth dynamics of uninterrupted rapid growth also occurred in some basal sauropodo- morphs, and that some basal sauropods retained the plesiomorphic cyclical growth patterns. Among the sauropodomorpha it appears that the basal taxa exploited different growth strategies, but the more derived Eusauropoda successfully utilized rapid, uninterrupted growth strategies.Facultad de Ciencias Naturales y Muse

Braincase of panphagia protos (dinosauria, sauropodomorpha)

We describe a partial braincase of the basal sauropodomorph Panphagia protos from the Upper Triassic (midCarnian) horizons of the Ischigualasto Formation. The disarticulated braincase from a subadult individual includes one frontal, both parietals, one prootic, and the supraoccipital. The frontal is longer anteroposteriorly than it is wide transversely, has a small anterolateral process, and an elongate oval depression for the olfactory bulb. The supraoccipital is broader transversely than it is deep dorsoventrally and lacks a pronounced median nuchal eminence. Some braincase features that characterize more derived basal sauropodomorphs are not present in Panphagia, including a broader frontal and reduced anterior tympanic and floccular recesses. Panphagia appears to represent an early stage in the evolution of sauropodomorph dinosaurs.Describimos la caja craneana parcial del sauropodomorfo basal Panphagia protos proveniente de horizontes del Triásico superior (Carniano medio) de la Formación Ischigualasto. La caja craneana desarticulada es de un individuo sub-adulto e incluye un frontal, dos parietales, un proótico y el supraoccipital. El frontal es más largo anteroposteriormente que ancho transversalmente, tiene un pequeño proceso anterolateral y una depresión alargada oval para el bulbo olfatorio. El supraoccipital es transversalmente más ancho que dorsoventralmente alto y carece de una eminencia nucal media pronunciada. Algunas de las características que caracterizan los neurocráneos de sauropodomorfos basales más derivados no están presentes en Panphagia, incluyendo el frontal ancho y la reducción de las cavidades timpánica anterior y flocular. Panphagia parece representar una etapa temprana en la evolución de los dinosaurios sauropodomorfos.Fil: Martínez, Ricardo Néstor. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Fisicas y Naturales. Instituto y Museo de Ciencias Naturales; ArgentinaFil: Haro, Jose Augusto. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Fisicas y Naturales. Instituto y Museo de Ciencias Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Apaldetti, Graciela Cecilia. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Fisicas y Naturales. Instituto y Museo de Ciencias Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

A New Basal Sauropodomorph (Dinosauria: Saurischia) from Quebrada del Barro Formation (Marayes-El Carrizal Basin), Northwestern Argentina

BACKGROUND: Argentinean basal sauropodomorphs are known by several specimens from different basins; Ischigualasto, El Tranquilo, and Mogna. The Argentinean record is diverse and includes some of the most primitive known sauropodomorphs such as Panphagia and Chromogisaurus, as well as more derived forms, including several massospondylids. Until now, the Massospondylidae were the group of basal sauropodomorphs most widely spread around Pangea with a record in almost all continents, mostly from the southern hemisphere, including the only record from Antarctica. METHODOLOGY/PRINCIPAL FINDING: We describe here a new basal sauropodomorph, Leyesaurus marayensis gen. et sp. nov., from the Quebrada del Barro Formation, an Upper Triassic-Lower Jurassic unit that crops out in northwestern Argentina. The new taxon is represented by a partial articulated skeleton that includes the skull, vertebral column, scapular and pelvic girdles, and hindlimb. Leyesaurus is diagnosed by a set of unique features, such as a sharply acute angle (50 degrees) formed by the ascending process of the maxilla and the alveolar margin, a straight ascending process of the maxilla with a longitudinal ridge on its lateral surface, noticeably bulging labial side of the maxillary teeth, greatly elongated cervical vertebrae, and proximal articular surface of metatarsal III that is shelf-like and medially deflected. Phylogenetic analysis recovers Leyesaurus as a basal sauropodomorph, sister taxon of Adeopapposaurus within the Massospondylidae. Moreover, the results suggest that massospondylids achieved a higher diversity than previously thought. CONCLUSIONS/SIGNIFICANCE: Our phylogenetic results differ with respect to previous analyses by rejecting the massospondylid affinities of some taxa from the northern hemisphere (e.g., Seitaad, Sarahsaurus). As a result, the new taxon Leyesaurus, coupled with other recent discoveries, suggests that the diversity of massospondylids in the southern hemisphere was higher than in other regions of Pangea. Finally, the close affinities of Leyesaurus with the Lower Jurassic Massospondylus suggest a younger age for the Quebrada del Barro Formation than previously postulated

A late norian-rhaetian coelophysid neotheropod (dinosauria, saurischia) from the quebrada del barro formation, Northwestern Argentina

Coelophysoids are the most abundant theropod dinosaurs known from the Late Triassic through Early Jurassic and represent the earliest major radiation of Neotheropoda. Within Coelophysoidea sensu lato, the most stable clade is Coelophysidae, which are small theropods characterized by long necks, and light and kinetic skulls. Coelophysids are the most abundant basal non-Tetanurae neotheropods known worldwide; however, until recently, they were unknown from South America. We report here a new coelophysid neotheropod, Lucianovenator bonoi gen. et sp. nov., from the late Norian-Rhaetian Quebrada del Barro Formation, northwestern Argentina. A phylogenetic analysis recovered Lucianovenator bonoi nested into the monophyletic group Coelophysidae in an unresolved clade, together with Coelophysis rhodesiensis and Camposaurus arizonensis. The presence of Lucianovenator in the late Norian-Rhaetian of Argentina increases the poor and scarce record of Triassic South American neotheropods, suggesting that the virtual absence of theropods in the fossil record during the Rhaetian is probably a taphonomic/stratigraphic bias instead of a decline in diversity and abundance after the Norian. Finally, the new finding corroborates the American endemism of coelophysid neotheropods in the Late Triassic and their worldwide distribution during the Early Jurassic, supporting the extreme faunal homogeneity hypothesized for Early Jurassic continental biotas.Fil: Martínez, Ricardo Néstor. Universidad Nacional de San Juan. Facultad de Ciencias Exactas Físicas y Naturales. Instituto y Museo de Ciencias Naturales. Área de Paleontología de Vertebrados; ArgentinaFil: Apaldetti, Graciela Cecilia. Universidad Nacional de San Juan. Facultad de Ciencias Exactas Físicas y Naturales. Instituto y Museo de Ciencias Naturales. Área de Paleontología de Vertebrados; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan. Centro de Investigaciones de la Geosfera y Biosfera. Universidad Nacional de San Juan. Facultad de Ciencias Exactas Físicas y Naturales. Centro de Investigaciones de la Geosfera y Biosfera; Argentin

Basal Sauropodomorpha (Dinosauria, Saurischia) of Gondwana

Sauropodomorfos basales de Argentina. Los sauropodomorfos basales incluyen a los sauropodomorfos no saurópods, que habitaron todos los continentes entre el Triásico Superior y el Jurásico Inferior. La evolución temprana de este grupo está bien documentada en el Carniano de Argentina y Brasil, alcanzando una rápida diversificación durante el Noriano y Retiano, incluyendo el registro de África, India y Europa. Luego de la extinción triásico/jurásica, la mayoría de los linajes rhaetianos continuaron en el Jurásico temprano, extendiéndose a Norteamérica, China y Antártida. Los sauropodomorfos carnianos no fueron diversos, abundantes o morfológicamente dispares, aunque durante el Noriano alcanzaron una gran diversidad tanto taxonómica como ecológica, gran abundancia y dominaron los ecosistemas terrestres. Para el Jurásico temprano, Sauropodomorpha alcanzó su mayor distribución geográfica y disparidad morfológica, desde formas pequeñas a medianas y facultativamente bípedas, hasta formas cuadrúpedas graviportales. La diversidad y disparidad de Sauropodomorpha cambió radicalmente en el Jurásico temprano, cuando todos sus linajes se extinguieron, con la excepción de los gravisáuridos, quienes dieron origen a Eusauropoda, convirtiéndose en los megaherbívoros dominantes por el resto del Mesozoico.Basal sauropodomorphs include the non-sauropod portion of Sauropodomorpha, which lived in all continental landmasses between the Late Triassic and Early Jurassic. The early evolution of the group is well recorded in Carnian beds of Argentina and Brazil, achieving a rapid diversification during Norian and Rhaetian, adding records from South Africa, India and Europe. After the Triassic/Jurassic extinction, most lineages of Rhaetian sauropodomorphs continued into the Early Jurassic, extending to North America, China, and Antarctica. Carnian sauropodomorphs were not diverse, abundant or morphologically disparate. During the Norian they notably diversified both taxonomically and ecologically, became abundant and dominated terrestrial ecosystems. By the Early Jurassic, Sauropodomorpha achieved their broadest geographical distribution and morphological disparity, ranging from small-medium size and facultatively bipedal forms to giant quadrupedal sauropods. The diversity and disparity of Sauropodomorpha changed radically at the end of the Early Jurassic when all lineages became extinct, except for the gravisaurians, which subsequently gave rise to Eusauropoda becoming the dominant megaherbivores during the rest of the Mesozoic.Fil: Otero, Alejandro. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Paleozoología Invertebrados; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Apaldetti, Graciela Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Juan; ArgentinaFil: Pol, Diego. Museo Paleontológico Egidio Feruglio; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin