Geographic and potential distribution of a poorly known south American bat, Histiotus macrotus (Chiroptera: Vespertilionidae)

The vespertilionid bat Histiotus macrotus occurs in western Argentina, central regions of Chile and south of Argentina and Chile, and it may be also present in Bolivia and southern Peru. In this work, we analyzed the geographic and potential distribution of a poorly known species of South American bat. As a tool, environmental niche modeling has been used to study the distributional patterns of species and more recently, taxonomic boundaries of cryptic species. We used MaxEnt v 3.3.e, Worldclim database and a vegetation map, covering the entire area of species' occurrence. We registered 64 localities from Argentina (43), Chile (10), Peru (8) and Bolivia (5). We divided recording localities in different datasets according to several taxonomic schemes, and analyzed potential distribution models separately (i.e., all known records; Argentina-Chile; Peru) in five different models. Models including all known localities showed a disjoint distribution, with two basic core areas of high predictive values, one in NW Argentina and another in southern Chile and SW Argentina separated by the South American Arid Diagonal. A third area appeared in Atacama and Sechura deserts in the models that included Peruvian and Bolivian localities. Model including only Peruvian localities showed the opposite pattern, with high predictive values only in arid environments from southern Peru. We interpreted that localities correctly assigned to H. macrotus belong to a taxonomic complex distributed in two contrasting areas, each one inhabited by a different taxon: 1) Bolivia and NW Argentina and 2) S and central Chile and SW Argentina. Given the systematic uncertainty of Histiotus, these two forms might be sister species or may not share an immediate common ancestor within the genus. Further, we consider that the specimens from localities referred to H. macrotus from southern Peru should be revised. These alternatives await a comprehensive molecular phylogenetic analysis of Histiotus.Fil: Giménez, Analía Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagóica. Universidad Nacional de la Patagonia ; Argentina. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Esquel. Laboratorio de Investigaciones en Evolución y Biodiversidad; ArgentinaFil: Giannini, Norberto Pedro. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Schiaffini, Mauro Ignacio. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Esquel. Laboratorio de Investigaciones en Evolución y Biodiversidad; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagóica. Universidad Nacional de la Patagonia ; ArgentinaFil: Martin, Gabriel Mario. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Esquel. Laboratorio de Investigaciones en Evolución y Biodiversidad; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagóica. Universidad Nacional de la Patagonia ; Argentin

Paleoenvironmental interpretation of the Holocene of Corrientes province, Argentina

The objective of the present paper is to recognize and reconstruct, from the analysis of pollen recovered from sedimentary cores, the predominant plant communities and their variations during the Holocene in Corrientes Argentina, in order to infer changes in climatic conditions, vegetation and paleoenvironmental evolution in the northeast of Argentina. For this study, lakes located in the central region of Corrientes province were selected, comprising part of the western margin of the Iberá Wetland. The palynological analysis of the paleocommunities shows, in a first stage of the mid Holocene, the predominance of marsh grasslands and hygrophilous communities that indicates humid to sub-humid environmental conditions. In a later stage of the mid Holocene, the paleocommunities show a characteristic association of wetlands, which together with the presence of Typha sp., would indicate sub-humid to humid conditions and waterlogged or flooded soils with slow-moving water. For the late Holocene, the paleocommunities show, initially, the presence of a grass-dominated herbaceous steppe, indicating environmental disturbances, which in the fossil record could reflect the combination of intense wind action under a dry climate. In a later stage, the frequency and variety of species characteristic of humid environments increase, dominated by marshy-herbaceous species, in addition to the development of the hygrophilous forest. Consequently, since the mid Holocene, the main climate factors responsible for the observed changes in wetland conditions were the location and intensity of the Atlantic and Pacific anticyclones in addition to changes in sea level. These forces mainly affected the distribution of precipitation, causing significant changes in the vegetation communities.Fil: Fernandez Pacella, Lionel Edgar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; ArgentinaFil: Lara, Maria Belén. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; Argentin