Fundacion Miguel Lillo

San Miguel de Tucumán, Argentina

Fundacion Miguel Lillo

San Miguel de Tucumán, Argentina
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Forasiepi A.M.,CONICET | Babot M.J.,Fundacion Miguel Lillo | Zimicz N.,National University of Salta
Journal of Systematic Palaeontology | Year: 2014

An almost complete skull of Australohyaena antiqua (Ameghino), from the Late Oligocene (Deseadan SALMA) of Cabeza Blanca, Chubut Province, Argentina is described and analysed. For more than a century, this species was represented by isolated teeth. The genus Australohyaena gen. nov. is proposed based on a phylogenetic reconstruction that demonstrates that A. antiqua is a Borhyaenidae (Mammalia, Sparassodonta), grouped with Arctodictis and Borhyaena, but not with Pharsophorus lacerans, the genus to which antiqua was formerly assigned. A. antiqua is recognized by several features on the skull, dentary and dentition. In addition, a short snout, large canines, deep jaw, reduced protocone and talonid determine A. antiqua as hypercarnivorous. A vaulted skull, well-developed temporal fossa and little difference on the jaw depth at p3 and m4, are suggestive of bone-cracker specializations. A. antiqua is within the largest Deseadan sparassodonts with a body mass of about 70 kg. Homoplasies are detected within borhyaenoids on lower molar cusps. The metaconid is lost within Sparassodonta, although Pharsophorus and borhyaenids retained the metaconid on m2-m4 or m2-m3. © 2014 The Trustees of the Natural History Museum, London.

Mangione S.,Fundacion Miguel Lillo | Mangione S.,National University of Salta | Garcia G.,National University of Salta | Cardozo O.M.,National University of Salta
Acta Zoologica | Year: 2011

In this study, we made a morphological analysis by optic microscopy of the dorsal and ventral skin of the body of Ceratophrys cranwellii, Lepidobatrachus llanensis and Chacophrys pierotti to verify if there exist shared integumental characters in relation to the Eberth-Katschenko layer (E-K layer). The presence of cells associated with this layer, historically considered acellular, is one of the leading characters. This study contributes to support that the E-K layer would be the remnant of an ancestral dermal skeleton and not a physiologically significant formation. Hence, the presence of cells associated with the E-K layer would represent a synapomorphy for Ceratophrydae. © 2010 The Authors. Acta Zoologica © 2010 The Royal Swedish Academy of Sciences.

Lavilla E.O.,Fundacion Miguel Lillo | Langone J.A.,Museo Nacional de Historia Natural | Caramaschi U.,Federal University of Rio de Janeiro | Heyer W.R.,Smithsonian Institution | De Sa R.O.,University of Richmond
Zootaxa | Year: 2010

The usage of the name Rana ocellata Linnaeus, 1758, is plagued by misidentifications and misinterpretations. After an exhaustive bibliographic review, we conclude that the Linnaeus 1758 name refers to Osteopilus brunneus (Gosse, 1851) from Jamaica, while the taxon currently known as Leptodactylus ocellatus corresponds to Rana latrans Steffen, 1815. Herein, we designate and provide descriptions of the neotypes of Leptodactylus latrans (Steffen, 1815), revalidated, new combination, and Osteopilus ocellatus (Linnaeus, 1758), new combination, as a senior synonym of Osteopilus brunneus (Gosse, 1851). Copyright © 2010 Magnolia Press.

Garcia-Lopez D.A.,CONICET | Garcia-Lopez D.A.,National University of Tucuman | Babot M.J.,Fundacion Miguel Lillo
Journal of Systematic Palaeontology | Year: 2015

Vertebrate-bearing deposits of the Geste Formation (Late Eocene) crop out in the Puna of Catamarca and Salta, north-western Argentina, and have yielded specimens of a variety of clades. Among these, mammals have particular importance since their record shows some taxonomic peculiarities when compared with that of adjacent units. Here we describe new material that includes Notoungulata of generalized morphology, two morphotypes of basal typotherians, and two interatheriid taxa (including Antofagastia turneri gen. et sp. nov.). These findings increase the variety of groups and provide new information about previously known taxa for this unit. Three phylogenetic analyses with different taxonomic contexts were performed. The first analysis includes the specimen referred to as 'Typotheria indet. A' in a data matrix of Paleogene notoungulates containing taxa traditionally referred as 'Oldfieldthomasiidae'. The specimen is grouped together with three 'oldfielthomasiids' (Maxschlosseria, Ultrapithecus and Dolichostylodon) in the resulting tree. The second analysis involves specimens referred to as 'Typotheria indet. B', 'archaeohyracids', mesotheriids and hegetotheriids. The results show these fossils to be part of a basal polytomy of 'early archaeohyracids'. Finally, a third analysis was conducted with Interatheriidae as the ingroup which recovered Antofagastia turneri at the base of a node including extra-Patagonian forms of non-interatheriine interatheriids plus Eopachyrucos and interatheriines. Although Antofagastia, Punapithecus and Chilean extra-Patagonian forms share some features, such as small size, they do not comprise a distinct clade. The notoungulate record of the Geste Formation shows some singularities in the context of north-western Argentinean Paleogene units, the presence of interatheriids and 'archaeohyracids' being the most striking of these. The differences exhibited can be partially explained by temporal factors, since recent isotopic data points to a Late Eocene age for this unit. Biogeographical isolation represents another possible explanation, because these levels appear to be deposited in an isolated geographical and geological context, suggesting intermontane basin deposition or local wedge-top basins. © The Trustees of the Natural History Museum, London 2014. All Rights Reserved.

The aim of this study was to make the aerobiological characterization of San Miguel de Tucumán city (26° 50'S, 65° 15'W) during the spring period august to november 2006. The sampling was performed with a Hirst type volumetric collector (Burkard model). Thirty pollen types were identified, providing a total of 3290 grains in the period. The 75,41% of pollen caught corresponded to pollen from shrub and tree species (PA), mainly exotic ones cultivated in the city and the native species growing on the eastern slopes of the Sierras de San Javier. The highest concentration was recorded in september with 1178 grains it was due to by the contribution of 19 tree pollen types being Broussonetia (65, 79%) the most abundant. At lower rates were recorded Morus (9, 24%), Alnus (7, 51%), Celtis (6, 50%), Fraxinus (2, 29%), Platanus (1, 90%), and Juglans (0, 73%). Intra-diurnal analysis shows a marked increase in night time which starts at 20:00 hours, increases between 22:00 and 2:00 to reach maximum at 8:00 in the morning. The minimum is recorded at 14:00 hours. During this period the main contribution corresponds to pollen taxa of trees and shrubs which have high levels of concentration in a short period of time.

Suarez G.M.,Fundacion Miguel Lillo | Suarez G.M.,National University of Tucuman | Schiavone M.M.,National University of Tucuman
Darwiniana | Year: 2013

The genus Pohlia is reported as a new record for Uruguay, where it is represented by two species: P. wahlenbergii and P. humilis (=P. tenuifolia). Pohlia humilis is also recorded as new for Colombia. We propose P. loriformis, a poorly known species described from Bolivia, as new synonym of P. humilis. We select lectotypes for P. loriformis and Mielichhoferia brachycarpa. We also include a key to the Pohlia species from Uruguay, and the South American synonyms, brief comments, distribution, and illustrations for P. humilis.

We studied the floristic composition and distribution of the riparian forest of two hydrographical systems in a subtropical Andean region. Using uni and multivariate techniques, we tested the hypotheses that a differentiable riparian forest exists, composed by native vegetation typical of the Yungas phytogeographical province, and that the distribution of vegetation varied significantly with geomorphologic characteristics. Parallel transects along the water courses were used to collect presence-absence data of vegetation in eleven sites. Detrended Correspondence Analysis defined a group of common riparian species for the studied area (Solanum riparium, Phenax laevigatus, Tipuana tipu, Cestrum parqui, Carica quercifolia, Acacia macracantha, Celtis iguanaea, Juglans australis, Pisoniella arborescens, Baccharis salicifolia, Cinnamomum porphyrium and Eugenia uniflora) and identified two reference sites. The distribution of the riparian vegetation varied significantly with the geomorphic characteristics along the studied sites. Riparian habitats were composed by native and exotic species. A distinct riparian flora, different in structure and function from adjacent terrestrial vegetation, could not be identified. Riparian species were similar to the adjacent terrestrial strata. These species would not be limited by the proximity to the river. Anthropogenic impacts were important factors regulating the introduction and increase of exotic vegetation. The lack of regulation of some activities in the zone could cause serious problems in the integrity of this ecosystem.

Argot C.,CNRS Center for Research on Palaeobiodiversity and Palaeoenvironments | Babot J.,Fundacion Miguel Lillo
Palaeontology | Year: 2011

Callistoe vincei Babot et al., 2002 is a Paleogene borhyaenoid known from exceptionally complete postcranial elements, which provides rare information about the anatomy and evolutionary history of metatherian predators during the South American Cenozoic. The axial skeleton of Callistoe is characterized by the peculiar transverse processes of the cervical vertebrae emphasizing lateral instead of sagittal traction. There is no clavicle and eighteen thoracolumbar vertebrae, of which only five are lumbars. The shoulder and elbow joints suggest movements restricted to parasagittal flexion/extension that are consistent with primarily terrestrial locomotion, as is also emphasized in Borhyaena tuberata and Lycopsis longirostrus. On the manus, the pollex is not reduced and the ungual phalanges indicate very long claws, similar to those observed in some extant digging taxa. This feature is unique to C. vincei among borhyaenoids. The knee joint is characterized by the presence of ossified patellae but shallow femoral trochleae. This joint suggests that the leg was nearly parasagittal, a position also inferred for Borhyaena. The astragalus shape is consistent with parasagittal flexion/extension, as in all Miocene-Pliocene borhyaenoids. The hind foot is characterized by reduced claws in comparison with the manus as well as the slenderness of the first and fifth digits, another peculiarity of C. vincei. The habitat of Callistoe was a temperate humid forest and according to the known fossil record, Callistoe was the largest mammalian predator of its time, sharing the predator ecological niche with crocodiles. © The Palaeontological Association.

Babot J.,Fundacion Miguel Lillo | Lopez D.A.G.,Instituto Miguel Lillo | Gaudin T.J.,University of Tennessee at Chattanooga
Journal of Vertebrate Paleontology | Year: 2012

In this study we describe an isolated petrosal from the middle Eocene of northwestern Argentina assigned to Dasypodinae (Mammalia, Xenarthra, Cingulata). The specimen was recovered from the Geste Formation, Antofagasta de la Sierra, Catamarca, Argentina. The material is an incomplete right petrosal preserving the pars cochlearis and the anterior third of the pars canalicularis. It is described in detail and compared with extant and fossil cingulates. Additionally, we performed a cladistic analysis in order to define its phylogenetic position. The most remarkable traits of this petrosal include an anteromedially-posterolaterally elongated promontorium, open cavum supracochleare, wide and smooth crista interfenestralis, roof of the post-promontorial tympanic sinus triangular, reduced, and well separated from the stapedius fossa, and poorly developed epitympanic wing and crista petrosa. The phylogenetic analysis reveals affinities with Dasypus and Stegotherium that are supported by the weakly developed crista petrosa and the reduced dorsal and ventral extension of the cerebellar surface of the pars cochlearis in relation to the size of the internal acoustic meatus. The information provided by this element indicates the existence of several characters that were already present in the Eocene, such as an elongated promontorium, and a step between the stapedius fossa and the roof of the post-promontorial tympanic sinus. We propose hypotheses of evolutionary change in the auditory region of cingulates, including the medial expansion of the roof of the post-promontorial tympanic sinus and the emergence of a conspicuous crista petrosa. © 2012 Taylor & Francis Group, LLC.

Suarez G.M.,Fundacion Miguel Lillo | Schiavone M.M.,Fundacion Miguel Lillo
Nova Hedwigia | Year: 2011

Pohlia section Pohlia is taxonomically revised for Central and South America. Five species are recognized in the study area (P. cruda, P. elongata, P. longicollis, P. nutans, and P. oerstediana). Seven new synonyms are proposed. Pohlia leptopoda, Webera grammocarpa, and W. crassicostata from Brazil, P. rusbyana, and P. subleptopoda from Bolivia, and P. leptodontium from Colombia are synonyms of P. elongata. P. elatior from New Zealand is a synonym of P. nutans. Eight new lectotypes are designated. Pohlia oerstediana is a new record to South America and the extension ranges of Latin American species are presented. All Neotropical species of Section Pohlia are described and illustrated and distribution maps are given. © 2011 J. Cramer in Gebr.

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