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1.
Heliyon ; 6(9): e04871, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32964163

RESUMO

In few groups of parasites have the patterns of distribution been studied using quantitative methods, even though, the study of these organisms indirectly provides information on the biogeographic history of their hosts, and in turn, the history of the hosts allows elucidation of speciation events of the parasites. Our objective was to quantitatively identify distributional congruence patterns of native fleas in northwestern Argentina. We analyzed 159 georeferenced distributional records of 47 species and six subspecies of fleas in northwestern Argentina using NDM/VNDM software. We found eight consensus areas, defined by 17 species and two subspecies, included in six patterns of distributional congruence (PDCs) with endemic and non-endemic fleas. The PDCs with the greatest values of endemicity (E) were mainly associated with Monte and Yungas Forests areas. All patterns indicated strong tendency of the Yungas Forests as a possible endemism area. Our results indicate that distributional congruence centers are generally located in Yungas Forests areas and highlight the importance of these areas in conservation and historical biology. This new information will allow delimitation of areas in the region at a more detailed resolution in the future.

2.
Mol Phylogenet Evol ; 152: 106926, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32771551

RESUMO

The Brazilian Atlantic forest is a tropical rainforest recognized as a hotspot of biodiversity, with high species richness and endemicity. This forest extends over a wide latitudinal range, bordering the entire Brazilian coastline, from sea level to high mountains over 2000 m.a.s.L., and presents a variety of environmental conditions and forest physiognomy. Despite many years of intense studies on animal biodiversity in the biome, there is a lack of information on meiofauna taxa causing several shortfalls in biodiversity knowledge of these tiny organisms. In this study, we address some of these shortfalls by describing a new species of Neogossea (Gastrotricha: Chaetonotida) from a lentic ecosystem in southeastern Brazil, surrounded by fragments of Atlantic Forest by using an integrative approach combining different morphological techniques and molecular data. We also point out new hypotheses of homologous structures due to scanning electron microscope observations of the new species. Additionally, we used two numerical methods to assess distribution patterns and historical regionalization of four freshwater meiofaunal taxa (Gastrotricha, Rotifera, Copepoda and Cladocera). For the first time, we accessed the areas of endemism in this biological hotspot based on aquatic fauna with a very peculiar life history. Due to sampling issues and meiofauna species being widespread, our results raise incongruences with previous endemism analyses on vertebrates and arthropods. Finally, we performed the first total-evidence phylogenetic analyses of benthic and semiplanktonic gastrotrichs based on 59 morphological characters and three molecular markers, employing a parsimony approach. The phylogenetic reconstruction supports the hypothesis of a single origin of semiplanktonic gastrotrichs, and both Dasydytidae and Neogosseidae families are monophyletic taxa as well as four non-monotypic genera.


Assuntos
Arthrodermataceae/classificação , Biodiversidade , Filogenia , Distribuição Animal , Animais , Arthrodermataceae/ultraestrutura , Brasil , Ecossistema , Água Doce , Microscopia Eletrônica de Varredura , Floresta Úmida
3.
Rev. biol. trop ; 68(2)jun. 2020.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1507670

RESUMO

Introducción: El Páramo se ha definido desde diversos acercamientos, teniendo en cuenta factores de fácil reconocimiento o medición. A nivel biogeográfico se ha evaluado con métodos ampliamente criticados para la identificación de áreas de endemismo. El análisis de endemicidad, pese a su importancia y amplio reconocimiento, no se ha utilizado como herramienta para evaluar el Páramo. Objetivo: Determinar si los páramos neotropicales es una o varias unidades biogeográficas. Métodos: Incluimos registros de Aves, Amphibia, Mammalia, Reptilia, Marchantiophyta y Spermatophyta, para los que encontramos 7 025 especies con 193 250 presencias viables obtenidas desde GBIF (Global Biodiversity Information Facility) [a septiembre de 2018]. Usamos cada grupo taxonómico como una partición independiente, y generamos particiones adicionales como plantas totales (Plantas-T: Marchantiophyta + Spermatophyta), animales totales (Animales-T: Aves + Amphibia + Mammalia + Reptilia) y evidencia total (Plantas-T + Animales-T). Utilizamos el criterio de optimalidad para identificar áreas de endemismo. Realizamos el análisis usando dos tamaños de cuadrícula 0.5 y 0.25°. Con las áreas obtenidas, calculamos la intersección con los polígonos que representan las definiciones de páramo generadas por otros autores. Resultados: Con los dos tamaños de cuadrícula identificamos áreas de endemismo en diferentes sectores; sin embargo, el tamaño de 0.25° nos permitió mayor resolución al identificar los sectores en alta montaña. Estos sectores corresponden a ocho zonas que denominamos subprovincias: Santa Marta-Perijá, Mérida, Santanderes-Boyacá, Cundinamarca, Cordillera Central-Occidental, Norte de Ecuador, Centro-Sur de Ecuador y Talamanca, las cuales fueron congruentes entre un 4 y un 66 % con las definiciones previas. Conclusiones: Páramo se ha planteado como una sola unidad biogeográfica; sin embargo, dado nuestros análisis, lo identificamos como ocho subprovincias biogeográficas, congruentes con estudios previamente publicados.


Neotropical páramos as biogeographic units. Introduction: Páramo has been defined from various points of view, which take into account different factors that are easy to recognize or measure, nevertheless at the biogeographic level it has been evaluated with criticized methods used to identify historical units. The analysis of endemicity, despite its importance and wide recognition, has not been used as a tool to evaluate Páramo. Objective: Determine whether the neotropical Páramo is one or several biogeographic units. Methods: We included distributional records from Aves, Amphibia, Mammalia, Reptilia, Marchantiophyta, and Spermatophyta. We found 7 025 species with 193 250 suitable occurrences obtained from the GBIF. We used each taxonomic group as an independent partition or as a component of a larger partition, such as total plants (Plants-T: Marchantiophyta + Spermatophyta), or total animals (Animals-T: Aves + Amphibia + Mammalia + Reptilia), or total evidence (Plants-T + Animals-T). In order to identify areas of endemism, we used the optimality criterion (NDM/VNDM) with grids of 0.5° or 0.25°. We calculated the intersection among polygons of previous definitions and the areas recovered in our analyses. Results: Both grid sizes, 0.25° and 0.5°, identified areas of endemism in different sectors along the Andean and Central American cordilleras, but only the 0.25° size allowed us to recognize areas/sectors with a higher resolution. We recovered eight areas, which were considered as subprovinces (Santa Marta-Perijá, Mérida, Santanderes-Boyacá, Cundinamarca, Central-Western Cordillera, Northern Ecuador, Central-South Ecuador, and Talamanca). These areas were between 4 and 66 % consistent with previous definitions. Conclusions: Páramo has been considered a single biogeographic unit, however, given our analyses we identified it as a unit composed of eight biogeographic subprovinces, which is consistent with some published studies.

4.
Zootaxa ; 4399(3): 423-433, 2018 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-29690324

RESUMO

Areas of endemism, or worthy for conservation, are mainly determined based on large data sets of vertebrates and plants. Herein, we investigated the global distribution at the species-level of the infraorder Tabanomorpha (Diptera, Brachycera), identifying areas of endemism for the group. We performed an endemicity analysis through a grid-based method-NDM/VNDM-using 1,385 species (6,392 geographical records) of Tabanomorpha. The grid size of the analysis was 7º and we applied the loose consensus rule (31%) in the recovered areas. Our results revealed 479 total areas of endemism and 18 consensus areas: the whole Neotropical region, six areas in the Nearctic region, two in the Palearctic region, and three areas in each the Oriental, Australian, and African regions. There are parallels among our results and previously proposed bioregionalisation schemes established by other taxa, showing a way forward for using insects to determine global patterns of endemism.


Assuntos
Dípteros , Animais , Austrália , Geografia , Vertebrados
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