Distribución de roedores sigmodontinos (rodentia: cricetidae) en pastizales de neblina del noroeste de Argentina

Distribution of sigmodontine rodents (Rodentia: Cricetidae) in the cloud highland grasslands of Northwestern Argentina. The sigmodontine rodents community of cloud highland grasslands ofNorthwestern Argentina is reported based on records obtained by trapping, analyses of owl pellets, study of museum specimens and literature. We recorded 34 species for this environment in Argentina, which is dominated by the Tribes Akodontini and Phyllotini. The Tribes Abrothrichini, Oryzomyini and Reithrodontini are poorly represented and two incertae sedis species complete this assemblage. Only Necromys lactens and Phyllotis osilae are characteristic elements of this environment and their ecotonalareas. Akodon boliviensis, A. lutescens, A. simulator, A. spegazzinii, A. sylvanus, Necromys lasiurus, Oxymycterus paramensis, Oligoryzomys sp., Oligoryzomys cf. O. flavescens, Calomys fecundus, C. lepidus, C. musculinus, Andinomys edax and Neotomys ebriosus present at least one record in pure cloud highland grasslands. Necromys amoenus, Graomys edithae, G. griseoflavus, Phyllotis caprinus and Tapecomys wolffsohni are found only in the ecotone with high Andean environments. Abrothrix illuteus, Akodon aliquantulus, A. budini, A. fumeus, Necromys sp., Oxymycterus sp. and Phyllotis anitae were recorded only in the ecotone with Chaco and Yungas forest at lower altitude. Finally, Oligoryzomys chacoensis, Calomys laucha and Eligmodontia moreni were considered dubious for this environment. The sigmodontines community of cloud highland grasslands shows a latitudinal turnover, with Akodon boliviensis, A. budini, A. fumeus, A. sylvanus, Necromys amoenus, Phyllotis caprinus and Tapecomys wolffsohni restricted to northernmost region, and Abrothrix andinus, A. illuteus, Akodon aliquantulus, Calomys fecundus, Graomys edithae, G. griseoflavus, Necromys lasiurus, Necromys sp., Oxymycterus sp., Reithrodon auritus and Phyllotis anitae distributed only in the south of the study area. Recent additions to the sigmodontine fauna of this region indicate that more work is needed to reach an adequate picture of the diversity and distribution for this group in this environment.Sobre la base de registros obtenidos mediante trampeos, análisis de regurgitados de lechuzas, estudio de especímenes de colecciones y revisión bibliográfica, reportamos las especies que componenla comunidad de roedores sigmodontinos de pastizales de neblina del noroeste argentino. Se registraron 34 especies para este ambiente en Argentina, dominadas por representantes de las tribus Akodontini y Phyllotini. Las tribus Abrothrichini, Oryzomyini y Reithrodontini están pobremente representadas y dos especies consideradas incertae sedis completan el ensamble. Sólo Necromys lactens y Phyllotis osilae son elementos característicos de este ambiente y sus áreas ecotonales. Akodon boliviensis, A. lutescens, A. simulator, A. spegazzinii, A. sylvanus, Necromys lasiurus, Oxymycterus paramensis, Oligoryzomys sp., Oligoryzomys cf. O. flavescens, Calomys fecundus, C. lepidus, C. musculinus, Andinomys edax y Neotomys ebriosus presentaron al menos un registro en pastizales de neblina puros. Necromys amoenus, Graomys edithae, G. griseoflavus, Phyllotis caprinus y Tapecomys wolffsohni se registraron sólo en el ecotono entre estos pastizales y ambientes semiáridos de altura. Abrothrix illuteus, Akodon aliquantulus, A. budini, A. fumeus, Necromys sp., Oxymycterus sp. y Phyllotis anitae fueron registrados sólo en el ecotono con bosques chaqueños y de Yungas a menores altitudes. Finalmente, Oligoryzomys chacoensis, Calomys laucha y Eligmodontia moreni fueron considerados de presencia dudosa. Latitudinalmente, la comunidad de sigmodontinos de los pastizales muestra un reemplazo de especies, con Akodon boliviensis, A. budini, A. fumeus, A. sylvanus, Necromys amoenus, Phyllotis caprinus y Tapecomys wolffsohni restringidas al sector norte y Abrothrix andinus, A. illuteus, Akodon aliquantulus, Calomys fecundus, Graomys edithae, G. griseoflavus, Necromys lasiurus, Necromys sp., Oxymycterus sp., Reithrodon auritus y Phyllotis anitae distribuidas sólo en el sur. Recientes adiciones a la fauna de sigmodontinos del noroeste señalan la necesidad de relevamientos adicionales para alcanzar un panorama adecuado de la diversidad y distribución del grupo en este ambiente

The Akodon boliviensis species group (Rodentia: Cricetidae: Sigmodontinae) in Argentina: species limits and distribution, with the description of a new entity

Akodon, with about 42 living species, is the most diverse genus of the subfamily Sigmodontinae. The Akodon boliviensis species group includes small-bodied, morphologically similar forms inhabiting Altiplano grasslands and grassland/forest ecotones of the eastern slope of the Andes, from central Peru to central Argentina. Northwestern Argentina contains the largest diversity of species of the group; the taxonomic treatment of these species has been based largely on unsupported and some weakly based opinions as underscored by recurrent changes. Based on morphologic and molecular data we assessed species limits among Argentinean populations of the Akodon boliviensis species group. We conclude that four species of the A. boliviensis species group inhabit northwestern Argentina. These are: A. boliviensis; A. caenosus (under which we synonymyze A. aliquantulus); A. spegazzinii (of which the nominal forms alterus, leucolimnaeus, and tucumanensis are junior synonyms); and A. sylvanus. Additionally, we described here a new species of the A. Boliviensis species group, Akodon polopi, which inhabits central Argentina. This is the only species of the A. boliviensis species group inhabiting the Sierras Grandes range (ca. 2000 m), mountain system of medium height isolated (ca., 600 km) from the main Andean chain by low elevation arid and semiarid environments. Additionally, our phylogenetic analysis suggests that the Akodon varius species group is polyphyletic.Fil: Jayat, Jorge Pablo. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Laboratorio de Investigaciones Ecológicas de las Yungas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Ortiz, Pablo Edmundo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Tucuman. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Instituto Miguel Lillo; ArgentinaFil: Salazar Bravo, Jorge. Texas Tech University; Estados UnidosFil: Pardiñas, Ulises Francisco J.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: D’Elía, Guillermo. Universidad de Concepción; Chil

Akodon polopi Jayat et al., 2010 is a senior subjective synomym of Akodon viridescens Braun et al., 2010

Two new taxa of species level were recently named for grass mice of the genus Akodon (Cricetidae, Sigmodontinae) from central Argentina: Akodon polopi Jayat, Ortiz, Salazar-Bravo, Pardiñas et D’Elía, 2010 and Akodon viridescens Braun, Mares, Coyner et Van Den Bussche, 2010. Several lines of evidence show that both taxa refer to the same biological species. Various morphologic characters enumerated by the two research teams for A. polopi and A. viridescens are coincident. The brownish coloration of the dorsal pelage, the chin with a small but distinguishable white patch, the tail of approximately 70% of head and body length, and the broad rostrum are among the diagnostic characters cited for both forms. Other additional characters mentioned in the diagnosis of only one of the nominal forms are also enumerated in the general description of the other. These include the size intermediate for the genus, the hour-glass shaped interorbital region with sharply squared posterior margins in older individuals, the anterior border of mesopterygoid fossa rounded with sides parallel or slightly diverging backward, and the parapterygoid fossae with straight and gradually divergent sides. Many additional features are mentioned for both nominal forms in their general descriptions.Fil: D' Elía, Guillermo. Universidad Austral de Chile. Instituto de Ecología y Evolución; ChileFil: Jayat, Jorge Pablo. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Laboratorio de Investigaciones Ecológicas de Las Yungas; ArgentinaFil: Ortiz, Pablo Edmundo. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Cátedra de Paleontología; ArgentinaFil: Salazar-bravo, Jorge. Texas Tech University. Department of Biological Sciences; Estados UnidosFil: Pardiñas, Ulises Francisco J.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; Argentin

Range extension of Oxymycterus wayku (Mammalia: Rodentia: Cricetidae), an endemic species from austral Yungas, and first record for Catamarca province, northwestern Argentina

Oxymycterus wayku Jayat, D’Elía, Pardinãs, Miotti & Ortiz, 2008, a rodent species recently described, is known in only four localities within the Subtropical Mountain Forests of the Yungas eco-region in Tucumán, northwestern Argentina. Specimens were recorded in an owl pellet sample during a recent survey. This record represents the first for Oxymycterus in Catamarca Province, extending approximately 60 km south its southern distribution in the region. Sixteen other small non-volant mammal species were recorded there, turning this area into one of the most diverse for this understudied group in Argentina

Seasonal variation in the diet of the Common Barn-Owl (Tyto alba) in a disturbed environment of the Argentinean Dry Chaco

Se estudió la dieta de la Lechuza de Campanario (Tyto alba) en un sector del Chaco Seco en Santiago del Estero, Argentina. A partir de 332 egagrópilas colectadas entre 2007 y 2009 se analizó la variación estacional en el número y la biomasa de los ítems presa, la diversidad y la amplitud de nicho trófico. Entre los 1170 individuos predados se registraron 14 ítems presa, correspondientes a mamíferos (87%), aves (7%) e insectos (6%). Los roedores cricétidos constituyeron el grupo más frecuente (85%) y con el mayor aporte de biomasa (>75%), con una amplia dominancia de Calomys spp. Durante el primer año la abundancia de micromamíferos en la estación seca alcanzó valores máximos, en tanto que aves e insectos mostraron el patrón opuesto. La diversidad y la amplitud de nicho trófico presentaron valores máximos durante la estación húmeda y la superposición trófica fue más baja entre muestras de estaciones diferentes. La variación estacional de la biomasa en la dieta se debió principalmente al mayor consumo de aves durante la estación húmeda de 2008. En la estación húmeda del segundo año de muestreo la dieta presentó un comportamiento anómalo, en algunos casos completamente opuesto a lo esperado, probablemente relacionado a una marcada disminución en las precipitaciones. Los resultados confirman una dieta generalista–oportunista, con un alto consumo de micromamíferos durante la estación seca explicado por sus tamaños poblaciones elevados. La modificación del ambiente explicaría la extrema dominancia de Calomys spp., como ya fuera documentado en otras áreas de Argentina.We studied the diet of the Common Barn-Owl (Tyto alba) in the Dry Chaco of Santiago del Estero, Argentina. From 332 pellets collected between 2007 and 2009 we analyzed the seasonal variation in number and biomass of prey-items, diversity, and trophic niche width. We identified 1170 individuals belonging to 14 prey-items, corresponding to mammals (87%), birds (7%) and insects (6%). Cricetid rodents were the most frequent group (85%) with the highest biomass contribution (>75%), being Calomys spp. the most abundant item. During the dry season of the first year, the abundance of micromammals reached the highest values while birds and insects showed the opposite pattern. Diversity and trophic niche width showed their highest values during the wet season and niche overlap was lower between samples of different seasons. Seasonal variation in biomass was mostly due to a higher consumption of birds during the wet season of 2008. In the wet season of the second year the diet showed an anomalous behaviour, in some cases showing the opposite of the expected patterns, probably related to a pronounced decrease in rainfall. The results of this study allow us to confirm a generalist-opportunistic diet, with high consumption of micromammals during the dry season probably explained by their high population sizes. Environmental modifications could be explaining the extreme dominance of Calomys spp., as it has been documented in other regions of Argentina

Uncovering cryptic diversity does not end: A new species of leaf-eared mouse, genus Phyllotis (Rodentia, Cricetidae), from Central Sierras of Argentina

Based on previously published molecular (mitochondrial) and herein provided morphological (qualitative and quantitative data) evidence, we describe a new species of leaf-eared mouse of the genus Phyllotis. The new species is morphometrically distinct when compared with other phylogenetically or geographically close species of Phyllotis, showing several quantitative differences in their external and craniodental characters (e.g., proportionally broader nasals and interorbital region, and proportionally smaller tympanic bullae). The new species is endemic to central Argentina, occurring on rocky grasslands at elevations of 650-2,800 m a.s.l. This is the only species of Phyllotis inhabiting the Central Sierras, a mountain system of medium elevation, isolated from the Andes by low elevation arid and semiarid environments.Fil: Teta, Pablo Vicente. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Jayat, Jorge Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - Tucumán. Unidad Ejecutora Lillo; ArgentinaFil: Steppan, Scott J.. University of Florida; Estados Unidos. Field Museum of National History; Estados UnidosFil: Ojeda, Agustina Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Provincia de Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Universidad Nacional de Cuyo. Instituto Argentino de Investigaciones de las Zonas Áridas; ArgentinaFil: Ortiz, Pablo Edmundo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Correlación Geológica. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Departamento de Geología. Cátedra Geología Estructural. Instituto Superior de Correlación Geológica; Argentina. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo; ArgentinaFil: Novillo, Agustina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Biodiversidad Neotropical. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Instituto de Biodiversidad Neotropical. Instituto de Biodiversidad Neotropical; ArgentinaFil: Lanzone, Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Biología Subtropical. Instituto de Biología Subtropical - Nodo Posadas | Universidad Nacional de Misiones. Instituto de Biología Subtropical. Instituto de Biología Subtropical - Nodo Posadas; ArgentinaFil: Ojeda, Ricardo Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Provincia de Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Universidad Nacional de Cuyo. Instituto Argentino de Investigaciones de las Zonas Áridas; Argentin

A new living species of the genus Ctenomys (Rodentia: Ctenomyidae) from central-western Argentina

Abstract The genus Ctenomys Blainville, 1826 includes 68 living species of small to medium-sized (100–1200 g) caviomorph rodents of subterranean habits. During the last decade, this genus has been the subject of numerous taxonomic studies, including the description of new species and the proposal of novel synonyms. Based on phylogenetic analysis of mitochondrial DNA sequences and qualitative and quantitative morphological traits, here we review the species boundaries of the tuco-tucos of the species group of C. mendocinus and describe a new species. The new species is morphologically distinct from other phylogenetically and geographically close species of Ctenomys (e.g., C. fochi, C. mendocinus), showing several differences in their craniodental traits (e.g., proportionally longer nasals and less globose tympanic bullae). The new species occurs in montane grasslands and shrublands of northwestern Mendoza (ca. 2710 m a.s.l.) and in lowlands (ca. 1000 m a.s.l.) of the Monte Desert ecoregion in an area highly impacted by accelerated processes associated with the wine industry

Taxonomy based on science is necessary for global conservation

Peer reviewe

Range extension of Cavia tschudii Fitzinger, 1867 (Mammalia: Caviidae) and first record in Catamarca, northwestern Argentina

We report the first record of the genus Cavia and the species Cavia tschudii (Rodentia, Caviidae) in Catamarca province, northwestern Argentina, which represents a range extension of about 110 km southward for the species. The cranial and dental remains were recovered from an owl pellet sample found in eastern slopes of the Ambato range, at 1600 m elevation, in a highland grasslands-Chaco Serrano ecotone. According to the environmental continuity along the Ambato range, we suggest that the presence of C. tschudii in southernmost Catamarca and northern La Rioja province is likely