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The Hypertrophy of the Tympanic Bulla in Three Species of Dasypodids (Mammalia, Xenarthra) from Argentina
Squarcia,Silvia Margarita; Sidorkewicj,Nora Silvia; Casanave,Emma Beatriz;
International Journal of Morphology , 2007, DOI: 10.4067/S0717-95022007000300021
Abstract: the morphology and relative size of the tympanic bulla of three species of dasypodids from argentina, chaetophractus villosus, c. vellerosus and zaedyus pichiy, were studied. the bulla was observed to be morphologically similar and evidently hypertrophied in the three species. the degree of hypertrophy was higher in c. vellerosus and c. villosus than in z pichiy. by means of ancova it was clear that, although c. villosus has a bigger skull than c. vellerosus, the relative size of their tympanic cavity was similar in both species. on the other hand, the skull of c. vellerosus and z pichiy are of similar size but the bulla was relatively shorter in the later
Los Xenarthra (Mammalia) del Ensenadense (Pleistoceno inferior a medio) de la Región Pampeana (Argentina)
Soibelzon, Esteban;Mi?o-Boilini, Angel Ramón;Zurita, Alfredo Eduardo;Krmpotic, Cecilia Mariana;
Revista mexicana de ciencias geológicas , 2010,
Abstract: xenarthra is a monophyletic group, characterized by a particular skeletal architecture, different to other placental mammals. its current distribution is exclusively neotropical; however, the fossil record indicates a greater distribution. the aim of this paper is to provide an updated list of the xenarthra of the lower to middle pleistocene (ensenadan stage) of the pampean region (argentina). the most conspicuous anatomical features that allowed the taxonomic identification offossil remains, especially those of particular biostratigraphic interest, are also briefly described andfigured here. we studied more than 700fossil remains mostly housed in palaeontological collections of argentina. the study of these specimens (from the pampean region), revealed that during the pleistocene there were marked variations in the composition and distribution ofthe faunas in general and particularly in xenarthrans. this situation was closely related to the great american biotic interchange and climatic oscillations occurring in the pleistocene. thus, the ensenadan fossil record of xenarthrans consists on exclusive taxa and numerous cases of first and last records. finally, we expect that this contribution provide a starting pointforfuture contributions in respect of the pleistocene fauna, not only from the pampean region, but also from the rest of argentina and south america.
Primer registro de Glyptodon Owen (Mammalia, Xenarthra, Cingulata) para el Pleistoceno de la provincia de Mendoza (Argentina)
Forasiepi,Analía M.; Martinelli,Agustín G.; Zurita,Alfredo E.; Ponce,Hernán;
Mastozoolog?-a neotropical , 2009,
Abstract: comparing with other regions of argentina, few pleistocene mammalian records are known from mendoza province. the genera previously recognized are: megatherium, mylodon, glossotherium, macrauchenia, paleolama, hippidion, and equus. in this note, the first occurrence of glyptodon sp. (xenarthra, cingulata, glyptodontidae) is reported. the material was found in outcrops of the el zampal formation located on the west margin of the tunuyán river, tupungato department. this finding represents the westernmost record of glyptodon in argentina.
PRIMER REGISTRO DE Glyptodon OWEN (MAMMALIA, XENARTHRA, CINGULATA) PARA EL PLEISTOCENO DE LA PROVINCIA DE MENDOZA (ARGENTINA)  [cached]
Analía M. Forasiepi,Agustín G. Martinelli,Alfredo E. Zurita,Hernán Ponce
Mastozoolog?-a neotropical , 2009,
Abstract: Poco se conoce aún sobre la fauna del Pleistoceno de la provincia de Mendoza en relación a otras regiones de la Argentina. Los géneros previamente reconocidos son: Megatherium, Mylodon, Glossotherium, Macrauchenia, Paleolama, Hippidion y Equus. En esta nota comunicamos los primeros restos de Glyptodon sp. (Xenarthra, Cingulata, Glyptodontidae), los que fueron hallados en la margen oeste del río Tunuyán, Departamento de Tupungato, en sedimentitas de la Formación El Zampal. Este espécimen de Glyptodon representa el registro más occidental para la Argentina.
Nuevos registros de pulgas (Siphonaptera) parásitas de dasipódidos (Mammalia: Xenarthra) en el noreste de la provincia de Buenos Aires, Argentina
Ezquiaga,María C.; Lareschi,Marcela; Abba,Agustín M.; Navone,Graciela T.;
Mastozoolog?-a neotropical , 2008,
Abstract: studies on the parasite fleas of argentinean xenarthrans are scarce. this report describes new species of fleas that parasitize armadillos of buenos aires province, argentina. polygenis (polygenis) platensis (rhopalopsyllidae) was collected from chaetophractus vellerosus, and tunga penetrans (tungidae) from chaetophractus villosus and dasypus hybridus. polygenis (p.) platensis constitutes the first record for dasipodids. this study extends the distribution of t. penetrans and cites two new parasite-host associations.
NUEVOS REGISTROS DE PULGAS (SIPHONAPTERA) PARáSITAS DE DASIPóDIDOS (MAMMALIA: XENARTHRA) EN EL NORESTE DE LA PROVINCIA DE BUENOS AIRES, ARGENTINA
María C. Ezquiaga,Marcela Lareschi,Agustín M. Abba,Graciela T. Navone
Mastozoolog?-a neotropical , 2008,
Abstract: Los estudios realizados sobre las pulgas parásitas de xenartros argentinos son escasos. Esta contribución da a conocer nuevas especies de pulgas que parasitan a dasipódidos en la provincia de Buenos Aires, Argentina. Polygenis (Polygenis) platensis (Rhopalopsyllidae) se halló en Chaetophractus vellerosus, y Tunga penetrans (Tungidae) en Chaetophractus villosus y Dasypus hybridus. El hallazgo de P. (P.) platensis constituye el primer registro para dasipódidos. Se amplió la distribución conocida de T. penetrans y se citan dos nuevas asociaciones parásito-hospedador.
Un nuevo Glyptodontidae (Mammalia, Xenarthra, Cingulata) del Mioceno de Patagonia (Argentina) y comentarios acerca de la sistemática de los gliptodontes "friasenses"
González-Ruiz, Laureano Raúl;Zurita, Alfredo Eduardo;Scillato-Yané, Gustavo Juan;Zamorano, Martin;Tejedor, Marcelo Fabián;
Revista mexicana de ciencias geológicas , 2011,
Abstract: in this contribution we described a new genus and species of glyptodontidae, coming from a new middle miocene fossiliferous locality named tranquera blanca (northwest of chubut province, patagonia argentina, patagonia). the most complete specimen recovered includes osteoderms from the cephalic shield, dorsal carapace and caudal armour. the most remarkable features of these new taxon are: a) osteoderms from the cephalic shield large and without the dorsal carapace ornamentation pattern; b) osteoderms from the dorsal carapace punctuated and with irregular edges; c) movable osteoderms in the antero-lateral region of the dorsal carapace; d) osteoderms from the postero-lateral region of the dorsal carapace with accessory antero-lateral peripheralfigures; e) osteoderms from de caudal rings of the caudal armour with large and numerous foramina; f large and rigid caudal tube absent. a revision of the previously recognized glyptodontidae for the patagonian middle miocene ("friasian" salma) indicates that taxa present includes (apart of the new taxon here described): propalaehoplophorinae gen. et sp. indet., eonaucum colloncuranum (glyptodontidae incertae sedis), propalaehoplophorus informis (propalaehoplophorinae), palaehoplophoroides rothi (palaehoplophorini), palaehoplophorus meridionalis (palaehoplophorini) and glyptodontidae gen. et sp. indet. finally, the type locality is tentatively correlated with other fossiliferous localities of the middle miocene.
Historia natural del piche llorón Chaetophractus vellerosus (Mammalia: Xenarthra: Dasypodidae) Natural history of the screaming hairy armadillo Chaetophractus vellerosus (Mammalia: Xenarthra: Dasypodidae)  [cached]
AGUSTíN M ABBA,GUILLERMO H CASSINI,MARCELO H CASSINI,SERGIO F VIZCAíNO
Revista chilena de historia natural , 2011,
Abstract: En este trabajo se presentan nuevos aportes sobre la historia natural del piche llorón Chaetophractus vellerosus (Mammalia: Xenarthra: Dasypodidae). Los estudios de campo fueron llevados a cabo en 100 ha de un establecimiento ganadero de la localidad de Magdalena, provincia de Buenos Aires, Argentina. Durante dos a os (2006-2008) se realizó un muestreo estacional de armadillos por captura y recaptura. Se obtuvieron datos de hábitos alimentarios, uso del espacio y del tiempo, comportamiento, termorregulación, datos poblacionales y morfológicos. Se realizaron 237 capturas de un total de 136 individuos. En la dieta el ítem principal registrado fue insectos coleópteros, seguido por material vegetal y peque os mamíferos; se observó una diferencia estacional en los hábitos alimentarios dada por una marcada caída de la ocurrencia de coleópteros durante la primavera. Durante las estaciones frías concentran su actividad al mediodía y primeras horas de la tarde y durante las estaciones cálidas el horario medio de actividad se da durante la tarde-noche. Seleccionan los suelos calcáreos arenosos y los pastizales de baja altura y alta cobertura de vegetación. El área de acción media registrada fue de 2670 m2. Son individuos asociales, con comportamiento diferente entre las estaciones y seleccionan los montes de tala para refugiarse. La temperatura rectal mostró correlaciones positivas con la temperatura ambiente y el peso. La proporción de sexos fue cercana a uno y no se observó dimorfismo sexual. Los resultados obtenidos concuerdan con lo observado para la especie en otras áreas distantes y con diferentes condiciones ambientales. Este trabajo representa un aporte en varios aspectos poco estudiados de una población aislada y bajo importantes presiones de uso y modificación de hábitat que la pueden llevar a la extinción en un mediano plazo. This contribution presents new data about the natural history of the screaming hairy armadillo Chaetophractus vellerosus (Mammalia: Xenarthra: Dasypodidae). A seasonal monitoring using the capture-recapture method was performed over the course of two years (2006-2008) in a 100 ha cattle farm in the locality of Magdalena, Buenos Aires province, Argentina. Data were collected on food habits, space and time use, behavior, thermoregulation, population data, and morphology. A total of 237 captures of 136 individuals were made. The main food items recorded were coleopterans, followed by plant matter and small mammals; a marked drop of coleopterans in the spring diet suggested seasonal differences in food habits. In the cold seasons, scre
On the taxonomic status of Megatherium sundti Philippi, 1893 (Mammalia: Xenarthra: Megatheriidae)
De Iuliis,Gerardo;
Ameghiniana , 2006,
Abstract: remains of a medium-sized megathere from pleistocene deposits near ulloma, bolivia, suggest that the commonly accepted synonymy of megatherium sundti philippi, 1893 with megatherium medinae philippi, 1893 (mammalia: xenarthra: megatheriidae) is unjustified. the strongest evidence supporting the distinction of these species is provided by their femora. in m. medinae the femur is plesiomorphic, bearing nearly parallel lateral and medial margins and an unreduced patellar trochlea. in m. sundti the femur bears strongly concave lateral and medial margins and a somewhat reduced patellar trochlea, resembling the derived condition in megatherium americanum cuvier, 1796. less marked morphological differences in the skull, mandible, and tibia are apparently associated with these distinct femoral morphologies. the differences are clearly sufficient for recognition of m . sundti as a valid species, distinct from m. medinae and another medium-sized megathere, megatherium tarijense gervais and ameghino, 1880, from pleistocene deposits near tarija, bolivia.
Historia natural del piche llorón Chaetophractus vellerosus (Mammalia: Xenarthra: Dasypodidae)
ABBA,AGUSTíN M; CASSINI,GUILLERMO H; CASSINI,MARCELO H; VIZCAíNO,SERGIO F;
Revista chilena de historia natural , 2011, DOI: 10.4067/S0716-078X2011000100004
Abstract: this contribution presents new data about the natural history of the screaming hairy armadillo chaetophractus vellerosus (mammalia: xenarthra: dasypodidae). a seasonal monitoring using the capture-recapture method was performed over the course of two years (2006-2008) in a 100 ha cattle farm in the locality of magdalena, buenos aires province, argentina. data were collected on food habits, space and time use, behavior, thermoregulation, population data, and morphology. a total of 237 captures of 136 individuals were made. the main food items recorded were coleopterans, followed by plant matter and small mammals; a marked drop of coleopterans in the spring diet suggested seasonal differences in food habits. in the cold seasons, screaming hairy armadillos were mainly active at noon and during the first hours of the afternoon, while in warm seasons their activity period shifted to the afternoon and night. the armadillos selected sandy-calcareous soils and preferred grasslands with low vegetation and high vegetation cover. the average home range was 2670 m2. screaming hairy armadillos were asocial. their behavior varied between seasons, and they selected the forest for refuge. rectal temperature was positively correlated with ambient temperature and body mass. the sex proportion was near to one, and no sexual dimorphism was observed. in general, the results of this study are in agreement with previous observations of c. vellerosus populations inhabiting different environmental conditions in very distant areas from the one monitored here. this work provides new information about different aspects of an isolated population that is subjected to high pressure due to habitat modification and use, and is therefore facing a high extinction risk.
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