Nuevos registros de Macropsalis forcipata, Cyanocorax caervlevs y Pyrodervs scvtatvs (aves: Aprimulgidae, Corvidae y Cotingidae) en el nordeste de la Provincia de Corrientes, Argentina

El Distrito de los Campos de la Provincia Fitogeográfica Paranaense (Cabrera, 1976), comprende el sur de Misiones y nordeste de Corrientes. Este Distrito, con 401 especies de aves, es una de las áreas con mayor riqueza ornitológica de Argentina (Giraudo y Povedano, 2004). Se hacen presentes en Corrientes numerosas especies que tienen aquí su límite austral de distribución, y no se encuentran en otras áreas de la provincia (Darrieu  Camperi, 1996). Dado que este Distrito es uno de los más modificados por acción antrópica en las últimas décadas, resulta imperativo que se tomen medidas tendientes a conservar su biodiversidad. En este sentido, el conocimiento de la distribución geográfica de las especies es de vital importancia, no sólo por el conocimiento en sí, sino porque brinda información útil para la conservación de las mismas. Por esto, se dan a conocer aquí nuevos registros de tres especies de aves en predios pertenecientes a la Empresa Las Marías S.A., en el departamento Santo Tomé, nordeste de la provincia de Corrientes

Adiciones a la avifauna del Parque Nacional Mburucuya, Corrientes, Argentina.

Aportamos nueva información sobre la composición, hábitat y distribución de la avifauna del Parque Nacional Mburucuyá. Presentamos datos de diez especies cuya presencia en el Parque no había sido registrada con anterioridad. Además mencionamos otras cinco especies que, aunque contaban con registros previos, poseen particular interés para esta área protegida por su valor para la conservación. El presente trabajo acrecienta el conocimiento de la avifauna del Parque y representa una importante herramienta para la planificación del manejo en el área protegida

Armadillo osteoderms altered by digestion and how taphonomy can help taxonomy

Diverse modifications of the original morphological features occur throughout the taphonomic history of osteological remains, which may lead in erroneous interpretations about the formation of an accumulation as well as taxonomic misidentifications. Here, we present a neo-taphonomic study in order to analyze and interpret the modifications generated by digestion on osteoderms of the armadillo Dasypus novemcinctus obtained from scats produced by Puma concolor. Results reveal intense breakage and modifications of the articular and broken edges, dorsal surface, bone tissues, and ornamentation pattern of the osteoderms. This work describes for the first time the modifications caused by digestion in armadillo osteoderms, improving the knowledge of preservation of this type of skeletal element and providing a modern analog that can be used to distinguish archeological and paleontological accumulations formed by predators from those generated by other processes. The recognition that digestion modifies the original ornamentation pattern is particularly significant because ornamentation features are used in nearly all taxonomic and phylogenetic studies of fossil cingulates. We use this new information to re-evaluate osteoderms recovered from carnivore coprolites of the classic Middle Miocene La Venta site (Colombia), which formed the basis for recognizing and characterizing the dasypodid species Nanoastegotherium prostatum. We highlight the importance of knowing with certainty the origin and taphonomic history of remains since, in the particular case of cingulates, taxonomic identification also has important biostratigraphic, paleoecological, paleoenvironmental, and paleobiogeographical implications.Depto. de Geodinámica, Estratigrafía y PaleontologíaFac. de Ciencias GeológicasTRUEUniversidad Nacional del SurUniversidad Nacional de La PampaUniversidad Complutense de MadridBanco Santanderpu

Temporal variation of bird assemblages in a wetland: influence of spatial heterogeneity

The temporal variation of bird assemblages at three sites within a wetland of the Parana River was examined. The aim was to obtain an overview of the influence of spatial heterogeneity on communities in such a variable environment as the wetlands. We recorded 1,662 individuals belonging to 139 species from 40 families. There were no significant differences between sites in richness, abundance nor diversity. Species richness in the first year was greater than during the second year. Number of resident and migrant species decreased in the second year. Community composition differed between the two years of study and was significantly different among seasons. Species were grouped into 19 trophic guilds. In this study, number of species and their abundances were not significantly different among sites; there were differences in the composition of birds among sites. Thus, the structure of the environments influenced the composition of assemblages in different areas. Guild composition remained fairly constant between years and among seasons. Geomorphological and hydrological dynamics of the river produce a heterogeneous availability of habitats and resources that affect the composition of bird assemblages. Annual and seasonal changes in meteorological variables can lead to changes in the structure and/or composition of those assemblages.Fil: Ronchi Virgolini, Ana Laura. Universidad Autónoma de Entre Ríos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Lorenzón, Rodrigo Ezequiel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto Nacional de Limnología. Universidad Nacional del Litoral. Instituto Nacional de Limnología; ArgentinaFil: Blake, John G.. University of Florida; Estados UnidosFil: Beltzer, Adolfo Hector. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto Nacional de Limnología. Universidad Nacional del Litoral. Instituto Nacional de Limnología; Argentin