Sample records for caluromys philander didelphimorphia

  1. Variations of chromosomal structures in Caluromys philander (Didelphimorphia: Didelphidae) from the Amazon region. (United States)

    Souza, Erica Martinha Silva de; Faresin e Silva, Carlos Eduardo; Eler, Eduardo Schmidt; Silva, Maria Nazareth F da; Feldberg, Eliana


    Caluromys is considered to be one of the most ancient genera of extant marsupials and is positioned among the basal taxa of the family Didelphidae. At least two species occur in Brazil, C. philander and C. lanatus, both of which have 2n = 14 chromosomes. For the first time, we present evidence of an intrapopulation polymorphism of the sexual chromosome pair in C. philander females from the Central Amazon region. Detailed cytogenetic results of animals from three localities on the Amazon region were analyzed using classical cytogenetics (NOR, C-Band and G-Band) and molecular techniques (18S rDNA and telomere probes). Similar to other conspecific individuals, the diploid number of these animals is 2n = 14, and their fundamental number is 24, with NOR present on the 6th autosomal pair. The X chromosome presented variation detectable by G banding, suggesting a pericentric inversion.

  2. Morphometrics of genus Caluromys (Didelphimorphia : Didelphidae) in northern South America


    López Fuster, María José; Pérez Hernández, Roger; Ventura Queija, Jacinto


    We reviewed the morphometric relationships between different forms of the woolly opossum, genus Caluromys, in northern South America by means of univariate and multivariate analyses of skull characters. Results revealed that specimens from Trinidad and northern Venezuela differ substantially in size and shape from other representatives of the genus. Thus, we propose that they should be attributed to Caluromys trinitatis rather to C. philander. Consequently, the specific name given by Thomas (...

  3. Geographic variation in Caluromys derbianus and Caluromys lanatus (Didelphimorphia: Didelphidae)


    Raul Fonseca; Diego Astúa


    We analyzed the geographic variations in the shape and size of the cranium and mandible of two woolly opossums, Caluromys derbianus and Caluromys lanatus. Using geometric morphometrics we analyzed 202 specimens of C. derbianus and 123 specimens of C. lanatus, grouped in 7 and 9 populations, respectively. We found sexual dimorphism in shape variables only in the dorsal view of the cranium of Caluromys derbianus, which is not associated with geographical origin. We detected geographic variation...

  4. Geographic variation in Caluromys derbianus and Caluromys lanatus (Didelphimorphia: Didelphidae

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    Raul Fonseca


    Full Text Available We analyzed the geographic variations in the shape and size of the cranium and mandible of two woolly opossums, Caluromys derbianus and Caluromys lanatus. Using geometric morphometrics we analyzed 202 specimens of C. derbianus and 123 specimens of C. lanatus, grouped in 7 and 9 populations, respectively. We found sexual dimorphism in shape variables only in the dorsal view of the cranium of Caluromys derbianus, which is not associated with geographical origin. We detected geographic variation in the size of the mandible in two populations (Nicaragua and Northern Panama, but no geographic variation in shape. The size of the cranium of C. lanatus varies significantly, with clinal variation in peri-Amazon populations, with a break between two populations, Bolivia and Paraguay. Shape analyses also revealed some separation between the Paraná population and all other populations. Our results suggest that the available name, Caluromys derbianus, should be maintained for all individuals throughout the geographic range of the species. The same is true for Caluromys lanatus, which can be separated into two distinct morphologic units, Caluromys lanatus ochropus, from the Amazon and Cerrado, and Caluromys lanatus lanatus, from the Atlantic forest.

  5. Carpal ontogeny in Monodelphis domestica and Caluromys philander (Marsupialia). (United States)

    Prochel, J A N; Sánchez-Villagra, Marcelo R


    Carpal bones have experienced numerous changes during marsupial evolution, even though their diversity and development remain poorly studied. The aim of this work was to document adult form and the pattern of mesenchymal tissue condensation and formation of chondrification and ossification centers in the hand of two marsupials. Two fundamental questions were asked: whether the loss of embryonic precursors was associated with the loss of adult elements, or whether there were developmental signs of ancestral mammalian elements that have been fused or lost in marsupial taxa. We were also interested to find out whether there is sexual dimorphismus in the carpals, as has been reported for some didelphids. Histological sections, cleared and stained specimens and macerated skeletons representing an ontogenetic series of Monodelphis domestica were used to document carpal development. Comparisons were made with perinatal stages of Caluromys philander and with adult specimens of other marsupials. A prenatal M. domestica in the 13th day after conception has a cell condensation that because of its position is homologized with a centrale, which is at birth already lost or fused. Neonatal M. domestica and C. philander have the number and arrangement of their adult carpal anatomy. Trapezium and trapezoid start ossification later than most other carpals, while pisiform and prepollex are the last to do so. Adult males of M. domestica have relatively larger and more robust pisiforms, compared to other carpals, than females. This sexual dimorphism develops relatively late as it was not recorded in male specimens around 160 days old. An extra sesamoid bone located just distal to the radius and proximo-palmar to the scaphoid was recorded in specimens of C. philander, C. derbianus and Didelphis virginiana.

  6. Behavior and maintenance of the woolly opossum (Caluromys) in captivity. (United States)

    Bucher, J E; Fritz, H I


    Circadian activity, general behavior, dietary requirements, and reproductive activity were recorded in a small laboratory colony (four females, six males) of two species of the woolly opossum (Caluromys lanatus and C derbianus) over a period of 3 years. The two species were indiscernable in all aspects of their behavior. Both were completely nocturnal and rarely active during daylight hours. General behavior was apparently related to many variables, particularly individual temperament and cage size. Even docile individuals were more excitable when housed in small cages. Although the woolly opossum is reported to prefer a meat diet, the opossums in this study remained healthy on a meat-egg-fruit diet, and showed a special liking for fruit, especially bananas. Vaginal smears indicated that females of the colony were cyclic, but all attempts to breed them were unsuccessful. Sexual behavior included pre-mount, pelvic-thrust displays on the part of the male, with complete repulsion by all females.

  7. Philander opossum (Marsupialia, a new host record for Sparganum of Lueheella Baer, 1924 (= Spirometra Mueller, 1937

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    Delir Corrêa Gomes


    Full Text Available Two samples of Sparganum, the larval form of Lueheella Baer, 1924 (= Spirometra Mueller, 1937 were recovered from Philander opossum (L. 1758 captured in Salobra, Mato Grosso State, Brazil, by Dr. Lauro Travassos in may, 1942. This is the first report of the presence of this larval form in P. opossum. Dealing with helminths recovered from Brazilian Marsupialia, deposited in Oswaldo Cruz Institute Helminthological Collection, we examined in two samples of the preserved material collected in Salobra. Mato Grosso State, nine larval forms (Sparganum of Lueheella sp. One of the samples, with six specimens, tissue. It is the first report of philander opossum harbouring this larval stage. The studied preserved wet material was stained and whole mounts were deposited in the Oswaldo Cruz institute Helminthological collection ns. 31.470 and 31.471. Measurements are in mm.Duas amostras de Sparganum, a forma larvar de Lueheella Baer, 1924 (=Spirometra Mueller, 1937, foram coletadas em Philander opossum (L., 1758 capturado em Salobra, MT, pelo Dr. Lauro Travassos, em maio de 1942. Essa é a primeira referência da presença desse estágio larvar em P. opossum.


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    Marcus Vinícius Vieira


    Full Text Available Performance measurements can be used to infer the fundamental niche ofspecies, allowing predictions of habitat or resource use in the absence of species interactions. We propose a standard set of tests to measure locomotory performance of arboreal vertebrates, and a procedure to develop ecomorphological models based on performance tests and path analysis. The proposed tests simulate habitat features such as support diameter and incline. Models of relationships between variables can be formulated, compared with path analysis, and the model of best fit chosen. This procedure was applied to the didelphid marsupial Philander frenata, comparing the effect of body shape on stride length and frequency in arboreal walking. The model includingpaths to stride length and frequency had a significant better fit than the model with paths only to stride length. An a posteriori model - obtained from the elimination of nonsignificant paths – suggested that the relative length of claws and tail were the moredeterminant of stride frequency, whereas stride length was more affected by the relative length of the limbs. These are hypotheses about an important aspect of the fundamental niche of didelphid marsupials, allowing inferences of niche similarity based on orphology. Independent data are necessary to test these hypotheses. = Medidas de desempenho utilizadas podem fornecer uma medida do nichofundamental, permitindo prever uso do habitat ou recursos na ausência de interações entre espécies. Propomos um conjunto padrão de testes de desempenho locomotor para vertebrados arborícolas, e um método para desenvolver modelos ecomorfológicos baseados em testes de desempenho e análise de caminhos. Os testes propostos simulamcaracterísticas do habitat como diâmetro e orientação de suportes. Modelos de relações entre variáveis podem ser formulados e comparados através da análise de caminhos, permitindo escolher o modelo de melhor ajuste aos dados. Este

  9. Precocity of Gnathostoma turgidum in naturally infected four-eyed opossum Philander opossum pallidus from Temascal, Oaxaca, Mexico. (United States)

    Almeyda-Artigas, Roberto Javier; Mosqueda-Cabrera, Miguel Angel; Sánchez-Núñez, Edmundo


    Two female advanced third-stage larvae of Gnathostoma turgidum recovered from the liver of one naturally infected four-eyed opossum Philander opossum pallidus collected in Oaxaca, Mexico, were morphologically examined. Because of some characteristics, the larvae do not fit into the typical advanced third-stage. The body shows a size at least three times larger than expected and rows of spines only in the anterior part of the body surface. Consequently, in this research, we document for the first time the precocity in third-stage larvae of G. turgidum, and we also highlight some facts about the fourth larval stage occurring in spirurins.

  10. PRESENCIA DEL ZORRO DE CUATRO OJOS (Philander opossum EN EL CULTIVO DE PIÑA (Ananas comusus

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    Javier Monge-Meza


    Full Text Available El objetivo de este trabajo fue determinar la presencia del zorro de cuatro ojos (Philander opossum en áreas de producción de piña orgánica (Ananas comusus, en Sa nta Ce cilia de La Cruz, Guanacaste, Costa Ri ca. Las capturas se realizaron con trampas grandes de golpe, en muestreos quincenales desde febrero del 2008 hasta febrero del 2009. Se logró la captura de ocho individuos, desde marzo hasta agosto, lo cual indica que la especie podría tener actividad reproductiva desde finales de la época seca y en la lluviosa. Al menos uno de los individuos consumió piña, según análisis de su contenido estomacal. Si n embargo, el nivel de daño observado en el campo no permite considerar a esta especie como una plaga de la piña, sino una especie oportunista que aprovecha frutos maduros dejados en el campo, después de la cosecha. La colecta de individuos en varios meses del año, indican que esta especie utiliza las plantaciones de piña orgánica como parte de su hábitat, lo cual contradice la idea generalizada que los monocultivos no proveen condiciones mínimas para que las especie s de vida silvestre lo visiten o lo habiten.

  11. Necrophagous Muscoids that develop in carcasses of Didelphis albiventris Lund, 1841 (Didelphimorphia, Didelphidae in Rio Grande do Sul, Brazil

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    Ândrio Zafalon da Silva


    Full Text Available Information regarding the similarity of the fauna that colonizes decomposing wildlife is insipient among the different carcass models. Species with different tissues and alimentary diets are hypothesized to be a colonization source of different necrophagous species. To verify this hypothesis, we observed the decomposition of a carcass of Didelphis albiventris Lund, 1841 (Didelphimorphia, Didelphidae, that had been run over by a vehicle. 2,273 adults were reared from specimens at immature stages collected on the carcass. The most representative species belongs to Calliphoridae, Muscidae, Sarcophagidae and Fanniidae, with numeric dominance of Lucilia eximia Wiedemann, 1819 (Diptera, Calliphoridae. Another six species were found, besides non-identified Fanniidae specimens. All species were colonizers of traditionally used forensic models.

  12. Humoral Immune Response Kinetics in Philander opossum and Didelphis marsupialis Infected and Immunized by Trypanosoma cruzi Employing an Immunofluorescence Antibody Test

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    Ana Paula Legey


    Full Text Available Philander opossum and Didelphis marsupialis considered the most ancient mammals and an evolutionary success, maintain parasitism by Trypanosoma cruzi without developing any apparent disease or important tissue lesion. In order to elucidate this well-balanced interaction, we decided to compare the humoral immune response kinetics of the two didelphids naturally and experimentally infected with T. cruzi and immunized by different schedules of parasite antigens, employing an indirect fluorescence antibody test (IFAT. Both didelphids responded with high serological titers to different immunization routes, while the earliest response occurred with the intradermic route. Serological titers of naturally infected P. opossum showed a significant individual variation, while those of D. marsupialis remained stable during the entire follow-up period. The serological titers of the experimentally infected animals varied according to the inoculated strain. Our data suggest that (1 IFAT was sensitive for follow-up of P. opossum in natural and experimental T. cruzi infections; (2 both P. opossum and D. marsupialis are able to mount an efficient humoral immune response as compared to placental mammals; (3 experimentally infected P. opossum and D. marsupialis present distinct patterns of infection, depending on the subpopulation of T. cruzi, (4 the differences observed in the humoral immune responses between P. opossum and D. marsupialis, probably, reflect distinct strategies selected by these animals during their coevolution with T. cruzi.

  13. El registro de Lestodelphys Tate, 1934 (Didelphimorphia, Didelphidae en el Pleistoceno tardío del noreste de la Provincia de Buenos Aires, Argentina

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    Agustín G. Martinelli


    Full Text Available Nuevos registros de Lestodelphys sp. (Marsupialia: Didelphimorphia: Didelphinae: Thylamyini son registrados en la base del Miembro Eloisa, Formación Río Luján (Pleistoceno tardío, provenientes de tres sitios localizados sobre la margen derecha de la ribera del Río Reconquista, Partido de Merlo, noreste de la Provincia de Buenos Aires (Argentina. Estos materiales constituyen los registros más boreales de Lestodelphys para la Provincia de Buenos Aires. Los registros consisten en cuatro mandíbulas. Estos tienen una combinación de caracteres que sugieren que (1 la especie fósil L. juga posee una alta variabilidad morfológica, por lo tanto la diagnosis actual debe ser revisada; o, (2 la validez de L. juga debiera no ser considerada, como fue sugerido por autores previos. El registro de Lestodelphys es utilizado como indicador ambiental ya que la especie viviente se registra en ambientes áridos a semiáridos. La presencia de los nuevos materiales en el Pleistoceno de Merlo refuerza las inferencias ambientales previamente mencionadas para los depósitos portadores.

  14. Phylogenetic measures applied to the conservation of Mexican marsupials Medidas filogenéticas aplicadas para la conservación de los marsupiales mexicanos

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    Margarita Medina-Romero


    Full Text Available The didelphimorphs in Mexico are found all over the country except for the Baja California Peninsula. The aim of this study was to use 3 methods to assess the phylogenetic diversity of the species Marmosa mexicana, Tlacuatzin canescens, Caluromys derbianus, Chironectes minimus, Didelphis marsupialis, Didelphis virginiana, Metachirus nudicaudatus, and Philander opossum, and to determine the potential conservation areas for these mammals. Phylogenetic information was included to measure the taxonomic weighting, taxonomic dispersion, and taxonomic distinctness within the Mexican biogeographic provinces. In addition, a gap analysis was performed to show which protected areas contain the didelphimorphs listed under a conservation category. Considering phylogenetic diversity with the former analysis, results indicate that the biogeographic provinces most important for conservation of didelphimorphs are the Gulf of Mexico, the Pacific Coast, and Oaxaca, although Soconusco and Sierra Madre del Sur also have to be considered. We also observed that not all of the richest sites corresponded with current protected areas. This study is important because it employed different conservation approaches based on phylogenetic measures and was focused on Mexican marsupials, of which 1 species is endemic and 2 are of conservation concern.El orden Didelphimorphia se encuentra distribuido en todo México excepto en la península de Baja California. En este trabajo se evaluó la diversidad filogenética para las especies Marmosa mexicana, Tlacuatzin canescens, Caluromys derbianus, Chironectes minimus, Didelphis marsupialis, Didelphis virginiana, Metachirus nudicaudatus y Philander opossum, y se determinaron las áreas potenciales de conservación para estos organismos. Para realizar los análisis de peso taxonómico, dispersión taxonómica y diferenciación taxonómica se incluyó información filogenética. También se realizó un análisis de vacíos y omisiones

  15. Phylogenetic measures applied to the conservation of Mexican marsupials Medidas filogenéticas aplicadas para la conservación de los marsupiales mexicanos


    Margarita Medina-Romero; Irene Goyenechea; Jesús Castillo-Cerón


    The didelphimorphs in Mexico are found all over the country except for the Baja California Peninsula. The aim of this study was to use 3 methods to assess the phylogenetic diversity of the species Marmosa mexicana, Tlacuatzin canescens, Caluromys derbianus, Chironectes minimus, Didelphis marsupialis, Didelphis virginiana, Metachirus nudicaudatus, and Philander opossum, and to determine the potential conservation areas for these mammals. Phylogenetic information was included to measure the tax...

  16. A geometric morphometric analysis of cranial and mandibular shape variation of didelphid marsupials

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    D. Astúa de Moraes


    Full Text Available Abstract The New World marsupial family Didelphidae is one of the oldest among mammals and is usually regarded as a morphologically conservative group. We analyzed cranial shape variation among six species of the six largest living genera of the family using two-dimensional landmark data. We captured and digitized video images of the skull and mandible for the following species: Caluromys philander (n = 65, Chironectes minimus (n = 30, Didelphis aurita (n = 70, Lutreolina crassicaudata (n = 37, Metachirus nudicaudatus (n = 77 and Philander frenata (n = 62. Fourteen landmarks were defined for the lateral, 25 for the ventral, 23 for the dorsal views of the skull, and nine on the mandibular lateral view. Sex, species, and interaction effects were analyzed with a two-way MANOVA on the matrices of coordinates aligned by general least squares. All four views had significant interactions. Canonical Variates Analysis was performed on sexes and species, and shape was regressed on the canonical variate scores for each species. Caluromys philander was clearly the most distinct species, with paedomorphic features that can be related to its arboreal habits. A conspicuous shortening of the rostrum distinguishes the highly carnivorous Lutreolina crassicaudata. Didelphis aurita and Philander frenata overlapped somewhat, reflecting shape similarities associated with their phylogenetic affinities, while the few differences observed are probably allometric consequences of size differences. Philander frenata and Chironectes minimus showed similar cranial shapes, while Metachirus nudicaudatus was distinctive with a broad and elongated rostrum. In spite of an overall similar shape, the geometric morphometric approach revealed several marked differences among species that can be related to their phylogenetic origin and their adaptive




    Studies of the chromosomes of four American marsupials demonstrated that Caluromys derbianus and Marmosa mexicana have a diploid number of 14 chromosomes, and that Philander opossum and Didelphis marsupialis have a diploid number of 22. The karyotypes of C. derbianus and M. mexicana are similar, whereas those of P. opossum and D. marsupialis are dissimilar. If the 14-chromosome karyotype represents a reduction from a primitive number of 22, these observations suggest that the change has occurred independently in the American and Australasian forms.

  18. Functional and evolutionary aspects of axial stability in euarchontans and other mammals. (United States)

    Granatosky, Michael C; Lemelin, Pierre; Chester, Stephen G B; Pampush, James D; Schmitt, Daniel


    The presence of a stable thoracolumbar region, found in many arboreal mammals, is considered advantageous for bridging and cantilevering between discontinuous branches. However, no study has directly explored the link between osteological features cited as enhancing axial stability and the frequency of cantilevering and bridging behaviors in a terminal branch environment. To fill this gap, we collected metric data on costal and vertebral morphology of primate and nonprimate mammals known to cantilever and bridge frequently and those that do not. We also quantified the frequency and duration of cantilevering and bridging behaviors using experimental setups for species that have been reported to show differences in use of small branches and back anatomy (Caluromys philander, Loris tardigradus, Monodelphis domestica, and Cheirogaleus medius). Phylogenetically corrected principal component analysis reveals that taxa employing frequent bridging and cantilevering (C. philander and lorises) also exhibit reduced intervertebral and intercostal spaces, which can serve to increase thoracolumbar stability, when compared to closely related species (M. domestica and C. medius). We observed C. philander cantilevering and bridging significantly more often than M. domestica, which never cantilevered or crossed any arboreal gaps. Although no difference in the frequency of cantilevering was observed between L. tardigradus and C. medius, the duration of cantilevering bouts was significantly greater in L. tardigradus. These data suggest that osteological features promoting axial rigidity may be part of a morpho-behavioral complex that increases stability in mammals moving and foraging in a terminal branch environment.

  19. Endoparásitos de micromamíferos del noroeste de Perú. 1: helmintos de marsupiales

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    Manuel Tantaleán


    Full Text Available En este trabajo, informamos los resultados del análisis parasitológico realizado a 40 individuos marsupiales de las especies Caluromys lanatus, Didelphis marsupialis, Marmosops noctivagus, Metachirus nudicaudatus, Marmosa (Micoureus regina, Monodelphis adusta, Philander andersoni y Philander opossum procedentes del departamento de Loreto, Perú. Se determinaron en total 11 especies de helmintos parásitos: Nematoda: Aspidodera sp., Cruzia tentaculata, Physaloptera mirandai, Physaloptera sp., Pterygodermatites sp., Trichuris sp., Turgida turgida, y Viannaia sp.; Trematoda: Podospathalium pedatum; Acanthocephala: Giganthorhynchus ortizi; y Pentastomida: ninfa. Los parásitos Trichuris sp., Pterygodematities sp., Turgida turgida, Viannaia sp. y Podospathalium pedatum son nuevos registros para el Perú. De igual manera, se registran por primera vez las siguientes asociaciones parásitos-huéspedes: Pterygodermatites sp.-Marmosa regina, Viannaia sp.- Marmosops noctivagus, Trichuris sp.-Marmosops cf. noctivagus, Podospathalium pedatum-Monodelphis adusta, Giganthorhynchus ortizi-Marmosops cf. noctivagus, y ninfas de pentastómidos-Marmosa regina y Metachirus nudicaudatus.

  20. Revision of the family Listropsoralgidae Fain, 1965 (Acariformes: Sarcoptoidea)-skin parasites of marsupials and rodents. (United States)

    Bochkov, Andre V; Oconnor, Barry M; Grootaert, Patrick


    The family Listropsoralgidae Fain, 1965 (Acariformes: Sarcoptoidea) is represented by the permanent skin ectoparasites associated with the South American and Australian marsupials (12 species) and the South American rodents of the family Echimyidae (1 species). The phylogenetic relationships of these mites (12 ingroup and 2 outgroup species) are reconstructed on the basis of the maximum parsimony (MP) and Bayesian analyses (BA) of 76 morphological characters. MP analysis confirmed monophyly of the listropsoralgid genera, the strict consensus of 18 trees generated by MP has the following pattern: Petauralges (Listropsoralgoides, Didelphialges, Listropsoralges) with poor resolution among species of the genus Listropsoralges. The same tree was generated by BA. Both successive and implied weighting strategies resulted in 7 MP trees: Petauralges (Listropsoralgoides (Didelphialges (Listropsoralges))). The relationships between species of the genus Listropsoralges received the poorest resolution: L. caenolestes (L. monodelphis, L. vossi, L. faini, L. brevisetosa (L. thylamys (L. marmosa-L. caluromys))). The host-parasite relationships of listropsoralgids are briefly discussed. The family Listropsoralgidae is taxonomically revised and to date includes 13 species in 4 genera. Six species and one genus are described as new: Listropsoralges brevisetosus sp. n. from Marmosa murina (Didelphimorphia: Didelphidae) from Peru, Listropsoralges similis sp. n. from Caluromys derbianus (Didelphidae) from Panama, Listropsoralges thylamys sp. n. from Thylamys venustus (Didelphidae) from Bolivia, Listropsoralges vossi sp. n. from Monodelphis domestica (Didelphidae) from Brazil, Listropsoralges caenolestes sp. n. from Caenolestes fuliginosus (Paucituberculata: Caenolestidae) from Ecuador, and Didelphialges metachirus gen. n., sp. n. from Metachirus nudicaudatus (Didelphidae) from Peru. The female of Listropsoralges faini Bochkov and Wauthy, 2009 is described for the first time.

  1. Genetic consequences of population subdivision: the marsupial Micoureus paraguayanus (Mammalia: Didelphimorphia as a case study

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    Daniel Brito


    Full Text Available Habitat fragmentation may cause population subdivision, affecting genetic variation, leading to heterozygosity loss and increased inbreeding, and contributing to population extinction. However, some genetic models have shown that under some conditions, population subdivision can favor heterozygosity and allelic diversity, and small populations may adapt to inbreeding. Here I investigate the relationship between population subdivision and genetic diversity for the marsupial Micoureus paraguayanus (Tate, 1931 using the program Vortex. Hypothetical populations of 100 and 2000 individuals were partitioned into 1, 2, 5 or 10 populations that were linked by varying rates of dispersal and also by sex-biased dispersal. Results suggested that heterozygosity and allelic diversity declined rapidly when a population was subdivided. Genetic and demographic stochasticity diminished the effectiveness of selection against recessive lethal alleles. Dispersal partly reversed the impacts of population subdivision. However, even high rates of dispersal did not eliminate demographic fluctuations or prevent extinction. Although gene flow largely prevented genetic divergence between populations, dispersal did not prevent heterozygosity from being lost more rapidly in subdivided populations than in single populations of equivalent total size. The dynamics of small, fragmented populations were critically dependent on interactions between demographic and genetic processes. Populations of M. paraguayanus may have to be relatively large and continuous to avoid significant losses of genetic diversity.

  2. Morfologia das glândulas salivares de Glironia venusta Thomas, 1912 (Didelphimorphia

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    Bruna S. Vieira


    Full Text Available O objetivo deste trabalho foi descrever a morfologia das glândulas salivares de Glironia venusta. Foi utilizado um exemplar coletado no resgate de fauna da Usina Hidroeletrica Teles Pires. Este foi fixado com solução de formaldeído a 10%. Para a análise macroscópica, as glândulas foram dissecadas e fotografadas in situ e para a microscopia foram retirados fragmentos das glândulas. Estes foram desidratados em concentrações crescentes de álcool, diafanizados em xilol, inclusos em parafina e corados com HE. G. venusta apresentou as glândulas mandibulares, parótidas, sublinguais, labiais e zigomáticas. As mandibulares se mostraram como estruturas alongadas, constituídas por lobos não septados e localizadas na porção anterior da região cervical. De formato triangular, a parótida estava localizada na depressão do masseter, ventral à cartilagem auricular. As sublinguais encontravam-se ventrais ao ramo da mandíbula, caudais ao digástrico. Foi observado na porção dorsoposterior à comissura labial, dorsal ao músculo orbicular da boca, as glândulas labiais, que apresentaram formato de "U". Já as glândulas zigomáticas acompanhavam a forma da porção anterior do arco zigomático, na margem infraorbital. As glândulas mandibulares e sublinguais apresentaram ácinos do tipo mucosos, com alguns ácinos serosos. A parótida era constituída por ácinos puramente serosos. Na glândula labial foi observado ácinos do tipo mistos ou seromucosos. Para a glândula zigomática não foi possível a realização da análise microscópica devido problemas de procedimento histológico. As características das glândulas salivares observadas em G. venusta se assemelham a de outros mamíferos onívoros, entretanto, apresentaram pequenas diferenças no que se refere à sua localização e forma.

  3. Distribution extension and sympatric occurrence of Gracilinanus agilis and G. microtarsus (Didelphimorphia, Didelphidae), with cytogenetic notes


    Geise,Lena; Astúa, Diego


    Gracilinanus microtarsus, from the Atlantic Forest and G. agilis, widespread in central Brazil in the Cerrado and in the northeastern Caatinga are two small Neotropical arboreal opossum species not frequently recorded in simpatry. Here we report eight G. agilis specimens from three localities and 17 G. microtarsus, from 10 localities, all in Minas Gerais, Rio de Janeiro and Bahia states. Species proper identification followed diagnostic characters as appearance of dorsum pelage, ocular-mark, ...

  4. The chromosomes of the Didelphidae (Marsupialia) and their evolutionary significance (United States)

    Reig, O.; Gardner, A.L.; Bianchi, N.O.; Patton, J.L.


    One hundred and seventy-seven specimens of American didelphids, representing 9 genera and 22 species have been studied for their chromosomal constitution. Didelphids are very conservative in chromosomal complements. All of the studied species can be sorted into one of three kinds of karyotypes: 2n= 14 (three species of Didelphis, one of Lutreolina, two of Philander, and one of Chironectes), 2n = 14 (eight species of Marmosa, one of Metachirus, three of Caluromys, and one of Dromiciops), and 2n= 18 (three species of Monodelphis). These karyotypes are stable, showing only minor variations within each basic pattern. It is concluded that chromosomals evolution in the Didelphidae proceededs from low numbers to higher numbers by a process of centromeric fissioning complemented by some pericentric inversions and/or translocations. The pattern of karyotypic stability is consistent with bradytely at the organismic level of evolution. This is explained by a low rate of regulatory genetic evolution promoted by epistatic selection favouring the retention of chromosomal arrangements highly advantageous for overall adaptation.

  5. Metazoarios parásitos de Tlacuatzin canescens y Marmosa mexicana (Mammalia: Didelphimorphia de México Metazoan parasites of Tlacuatzin canescens and Marmosa mexicana (Mammalia: Didelphimorphia from Mexico

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    Carmen Guzmán-Cornejo


    Full Text Available Como parte de un estudio sobre los metazoarios parásitos de mamíferos de México se recolectaron 4 ejemplares de ratones tlacuache: 2 de Tlacuatzin canescens (Allen, 1893 procedentes de Oaxaca y 2 de Marmosa mexicana Merriam, 1897 de Veracruz. Se presentan 5 registros nuevos de hospedero y localidad para ácaros de las especies Ixodes luciae Sénevet, 1940, Ixodes sinaloa Kohls y Clifford, 1966, las pulgas Plusaetis mathesoni (Traub 1950 y Polygenis martinezbaezi Vargas 1951, así como para el cestodo Hymenolepis sp. y por primera vez en México se registra el nematodo Hoineffia simplicispicula Navone, Suriano y Pujol, 1991.As a part of an ongoing project to inventory the metazoan parasites of Mexican mammals, 4 specimens of 2 species of mouse opossums (2 Tlacuatzin canescens [Allen, 1893] and 2 Marmosa mexicana Merriam, 1897, were collected from Oaxaca and Veracuz states, Mexico, respectively. Five new locality and host records are presented for the acari Ixodes luciae Sénevet, 1940, Ixodes sinaloa Kohls and Clifford, 1966, of fleas Plusaetis mathesoni (Traub 1950, and Polygenis martinezbaezi Vargas 1951, as well as the cestode Hymenolepis sp., while the nematode Hoineffia simplicispicula Navone, Suriano and Pujol, 1991, is recorded for the first time in Mexico.

  6. Endogenous Life Cycle of Eimeria marmosopos (Apicomplexa: Eimeriidae) from the Opossum, Didelphis marsupialis (Didelphimorphia: Didelphidae) in Costa Rica. (United States)

    Chinchilla, Misael; Valerio, Idalia; Duszynski, Donald


    The endogenous life cycle of Eimeria marmosopos was studied in experimentally infected young opossums, Didelphis marsupialis . All the endogenous stages were located in the epithelial cells of villi in the small intestine. Giemsa-stained mucosal scrapings and histological sections were studied for the diagnosis of all the life cycle stages. Eimeria marmosopos has 3 generations of meronts (M) that differ by size, shape, and number of merozoites (m), which also differ in their size, shape, and location of their nuclei within the cytoplasm of the meronts. The 3 meront types, M(1)-M(3), respectively, had 8-15 (m(1)), 4-9 (m(2)), and 22-30 (m(3)) merozoites. Macrogametocytes and microgametocytes, as well as macrogametes and microgametes, completed the sexual cycle, finishing with the formation of unsporulated oocysts. This parasite's endogenous development produced severe intestinal lesions in experimentally infected opossums. There are 56 Eimeria species known from all marsupials worldwide, but this is the first complete life cycle in which both the asexual and sexual stages have been documented.

  7. Anomalous colour in Neotropical mammals: a review with new records for Didelphis sp. (Didelphidae, Didelphimorphia and Arctocephalus australis (Otariidae, Carnivora

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    MSL. Abreu

    Full Text Available Anomalous colourations occur in many tropical vertebrates. However, they are considered rare in wild populations, with very few records for the majority of animal taxa. We report two new cases of anomalous colouration in mammals. Additionally, we compiled all published cases about anomalous pigmentation registered in Neotropical mammals, throughout a comprehensive review of peer reviewed articles between 1950 and 2010. Every record was classified as albinism, leucism, piebaldism or eventually as undetermined pigmentation. As results, we report the new record of a leucistic specimen of opossum (Didelphis sp. in southern Brazil, as well as a specimen of South American fur seal (Arctocephalus australis with piebaldism in Uruguay. We also found 31 scientific articles resulting in 23 records of albinism, 12 of leucism, 71 of piebaldism and 92 records classified as undetermined pigmentation. Anomalous colouration is apparently rare in small terrestrial mammals, but it is much more common in cetaceans and michrochiropterans. Out of these 198 records, 149 occurred in cetaceans and 30 in bats. The results related to cetaceans suggest that males and females with anomolous pigmentation are reproductively successful and as a consequence their frequencies are becoming higher in natural populations. In bats, this result can be related to the fact these animals orient themselves primarily through echolocation, and their refuges provide protection against light and predation. It is possible that anomalous colouration occurs more frequently in other Neotropical mammal orders, which were not formally reported. Therefore, we encourage researchers to publish these events in order to better understand this phenomenon that has a significant influence on animal survival.

  8. The multiple and complex and changeable scenarios of the Trypanosoma cruzi transmission cycle in the sylvatic environment. (United States)

    Jansen, Ana Maria; Xavier, Samanta C C; Roque, André Luiz R


    In this study, we report and discuss the results generated from over 20 years of studies of the Trypanosoma cruzi sylvatic transmission cycle. Our results have uncovered new aspects and reviewed old concepts on issues including reservoirs, true generalist species, association of mammalian species with distinct discrete typing units - DTUs, distribution of T. cruzi genotypes in the wild, mixed infections, and T. cruzi transmission ecology. Using parasitological and serological tests, we examined T. cruzi infection in 7,285 mammalian specimens from nine mammalian orders dispersed all over the Brazilian biomes. The obtained T. cruzi isolates were characterized by mini-exon gene sequence polymorphism and PCR RFLP to identify DTUs. Infection by T. cruzi was detected by serological methods in 20% of the examined animals and isolated from 41% of those infected, corresponding to 8% of all the examined mammals. Each mammal taxon responded uniquely to T. cruzi infection. Didelphis spp. are able to maintain high and long-lasting parasitemias (positive hemocultures) caused by TcI but maintain and rapidly control parasitemias caused by TcII to almost undetectable levels. In contrast, the tamarin species Leontopithecus rosalia and L. chrysomelas maintain long-lasting and high parasitemias caused by TcII similarly to Philander sp. The coati Nasua nasua maintains high parasitemias by both parental T. cruzi DTUs TcI or TcII and by TcII/TcIV (formerly Z3) at detectable levels. Wild and domestic canidae seem to display only a short period of reservoir competence. T. cruzi infection was demonstrated in the wild canid species Cerdocyon thous and Chrysocyon brachyurus, and positive hemoculture was obtained in one hyper carnivore species (Leopardus pardalis), demonstrating that T. cruzi transmission is deeply immersed in the trophic net. T. cruzi DTU distribution in nature did not exhibit any association with a particular biome or habitat. TcI predominates throughout (58% of the T. cruzi

  9. Karyotype characterization and nucleolar organizer regions of marsupial species (Didelphidae from areas of Cerrado and Atlantic Forest in Brazil

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    Núbia P. Pereira


    Full Text Available The karyotypes of 23 specimens belonging to 16 species from nine genera of Brazilian marsupials (family Didelphidae were studied. The animals were collected in eight localities of Cerrado or Atlantic Forest biomes in the states of Goiás, Tocantins and São Paulo. The karyotypes were analyzed after conventional Giemsa staining and silver staining of the nucleolus organizer regions (Ag-NORs. New karyotypic data were obtained for Gracilinanus microtarsus (2n = 14, FN = 24, Marmosops paulensis (2n = 14, FN = 24 , Micoreus paraguayanus (2n = 14, FN = 20 and Monodelphis rubida (2n = 18, FN = 32 and are discussed in detail. The karyotypes of G. microtarsus , M. paulensis and M. paraguayanus include three large pairs of submetacentrics (pairs 1, 2 and 3 and a medium-sized metacentric or submetacentric pair 4. Pairs 5 and 6 are small submetacentrics in G. microtarsus and M. paulensis and acrocentrics in M. paraguayanus . M. paulensis presented a single Ag-NOR in pair 6 (6p6p, while M. paraguayanus exhibited multiple Ag-NORs in pairs 5 and 6 (5pq5pq6p6p. There was variation in size and morphology of the sex chromosomes among these species. Monodelphis rubida presented a karyotype with 2n = 18 and FN = 32 composed of a large submetacentric pair 1, a medium-sized metacentric pair 2 and six pairs of submetacentrics (pairs 3 through 8. The X was a small acrocentric and the Y was dot-like. A single Ag-NOR bearing pair (5p5p characterized M. rubida. Relevant karyotypic information was obtained for 19 specimens belonging to 12 species collected in areas sampled for the first time [ Caluromys lanatus and C. philander (2n = 14, FN = 20, Gracilinanus emiliae (2n = 14, FN = 24, Marmosa murina , Metachirus nudicaudatus and Micoureus demerarae (2n = 14, FN = 20, Monodelphis americana (2n = 18, FN = 32 and M. domestica (2n = 18, FN = 20, and Didelphis marsupialis, Philander frenata, P. opossum and P. sp (2n = 22, FN = 20]. Although the karyotypes were relatively

  10. Distribuição geográfica de pequenos mamíferos não voadores nas bacias dos rios Araguaia e Paraná, região centro-sul do Brasil Geographic distribution of small non-volant mammals in the Araguaia and Paraná basins, south-central region of Brazil

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    Nilton C. Cáceres


    Full Text Available Realizaram-se amostragens de pequenos mamíferos em duas bacias hidrográficas do Brasil central pertencentes aos rios Araguaia e Paraná com intuito de descrever a composição de espécies de pequenos mamíferos de hábito florestal e comparar suas distribuições geográficas. Quatorze pontos de coleta foram amostrados, subdivididos em oito na bacia do Rio Paraná e seis na bacia do Rio Araguaia. Foram registradas 20 espécies de pequenos mamíferos na região (oito de marsupiais e 12 de roedores, sendo 16 delas por meio de armadilhas metálicas (5.253 armadilhas-noite e oito delas por meio de armadilhas de queda (224 baldes-noite, totalizando 161 capturas de 139 indivíduos. A bacia do Rio Paraná apresentou 16 espécies (armadilhas-noite: 3.115; baldes-noite: 104 e a bacia do Araguaia apresentou 11 espécies (armadilhas-noite: 2.138; baldes-noite: 120, sendo que as riquezas foram similares quando aplicado o método da rarefação. Das 20 espécies registradas, sete (35% ocorreram em ambas as bacias. Apesar da elevada riqueza de espécies amostrada, destacou-se a elevada abundância do marsupial Didelphis albiventris Lund, 1840. As espécies de marsupiais amostradas foram D. albiventris, Caluromys philander (Linnaeus, 1758, Cryptonanus cf. agricolai Voss, Lunde & Jansa, 2005, Gracilinanus agilis (Burmeister, 1854, G. microtarsus (Wagner, 1842, Lutreolina crassicaudata (Desmarest, 1804, Marmosa murina (Linnaeus, 1758, e Philander opossum (Linnaeus, 1758. As espécies de roedores amostradas foram Akodon gr. cursor, Calomys tener (Winge, 1887, Nectomys rattus (Pelzen, 1883, N. squamipes (Brants, 1827, Oecomys bicolor (Tomes, 1860, Oryzomys maracajuensis Langguth & Bonvicino, 2002, Oryzomys cf. marinhus, O. megacephalus (Fischer, 1814, Oligoryzomys fornesi (Massoia, 1973, Oligoryzomys sp., Proechimys longicaudatus (Rengger, 1830 e P. roberti (Thomas, 1901. A ampliação da distribuição de algumas espécies é discutida, assim como aspectos

  11. Small mammals (Chiroptera, Didelphimorphia, and Rodentia) from Jaíba, middle Rio São Francisco, northern Minas Gerais State, Brazil


    Nogueira,Marcelo Rodrigues; Pol,André; Pessôa,Leila Maria; Oliveira,João Alves de; Peracchi,Adriano Lúcio


    We report the results of small mammals inventories conducted in the region of Jaíba, northern Minas Gerais state, southeastern Brazil, from 1990 to 1995. This region is located in the southern limit of the Caatinga biome, and harbors a unique set of natural ecosystems and extensive agricultural areas. With a total effort of 2964 trap-nights and 44 net sessions, we captured 893 small mammals from 46 species, including four marsupials, 13 rodents, and 29 bats. We report on species that are...

  12. Ocorrência de Ixodes loricatus Neumann, 1899 (Acari: Ixodidae) parasitando Didelphis albiventris (Lund, 1841), (didelphimorphia: didelphidae), em Campo Grande, MS



    Este é primeiro relato da ocorrência de Ixodes no Estado do Mato Grosso do Sul e primeiro caso identificado de Ixodes loricatus Neumann, 1899, parasitando Didelphis albiventris no município de Campo Grande, MS, Brasil. This is first report of occurence of Ixodes in the State of Mato Grosso do Sul and first description of Ixodes loricatus Neumann, 1899, parasitizing Didelphis albiventris in Campo Grande, MS, Brazil.

  13. Sleeping sites of woolly mouse opossum Micoureus demerarae (Thomas (Didelphimorphia, Didelphidae in the Atlantic Forest of south-eastern Brazil Sítios de dormida da cuíca Micoureus demerarae (Thomas (Didelphimorphia, Didelphidaa na Floresta Atlântica do sudeste do Brasil

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    Edsel A. Moraes Junior


    Full Text Available Micoureus demerarae (Thomas, 1905 is a medium-sized marsupial, around 130 g, with a nocturnal habit and insectivorous-omnivorous diet. From August 2001 to July 2002, seven individuals, three males and four females, were monitored with radio-telemetry in Reserva Biológica União, state of Rio de Janeiro, Brazil, aiming to investigate and describe the sleeping sites used by this marsupial. Fifty eight sleeping sites were located, most of which (70,7% in palm trees Astrocaryum aculeatissimum (Schott Burret, and the remaining in other tree species (29,3%, a significant difference (chi2 test; p Micoureus demerarae (Thomas, 1905 é um marsupial de tamanho médio, cerca de 130 g, de hábito noturno e arborícola e dieta insetívora-onívora. No período de agosto de 2001 a julho de 2002, sete indivíduos, três machos e quatro fêmeas, foram acompanhados, através de rádio-telemetria, na Reserva Biológica União, Rio de Janeiro, com o objetivo de investigar e descrever os abrigos utilizados por essa espécie de marsupial. Foram localizados 58 abrigos, a maioria dos quais (70,7% em palmeiras Iri Astrocaryum aculeatissimum (Schott Burret e o restante em outras espécies de árvores (29,3%, uma diferença significativa (teste chi2; p < 0,005. Esta preferência por palmeiras não foi significativamente diferente entre os sexos (teste chi2; p = 0,920. Em 31 abrigos (53,4% do total o local exato onde o animal se encontrava pode ser localizado: nas palmeiras os animais sempre estavam alojados no local de inserção dos pecíolos junto ao tronco e a uma altura média de 4,66 ± 1,36 m, enquanto nas demais espécies de árvores, sete animais estavam em emaranhados de cipós e dois em ocos, a uma altura média de 10,67 ± 2,75 m. Esta diferença de altura entre abrigos em iris e não iris foi significativa (teste Mann Whitney; p < 0,001. Os resultados indicam que as palmeiras iris são um importante recurso para M. demerarae. A preferência por A. aculeatissimum se deve provavelmente à maior proteção contra predadores exercida pelos numerosos espinhos presentes nesta espécie.

  14. Identidade, riqueza e abundãncia de pequenos mamíferos (Rodentia e Didelphimorphia de área de Floresta com Araucária no estado do Paraná, Brasil

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    Guilherme Grazzini


    Full Text Available Roedores e Marsupiais são componentes importantes da fauna na região Neotropical. Estudos sobre a riqueza e abundância destes animais são raros na Floresta Ombrófila Mista (FOM e aqui apresentamos um inventário conduzido na Floresta Nacional de Piraí do Sul. Esta área possui uma área aproximada de 150 ha, cercada por pastos e plantações de Pinus. A amostragem foi feita através de armadilhas de queda, Sherman e Tomahawk, dispostas nos principais tipos de vegetação encontrados. Pelo menos um casal de cada espécie foi coletado. Como resultado, durante 5.892 armadilhas.noite nós obtivemos um total de 1.049 capturas, representando 17 espécies: Akodon montensis, Bibimys labiosus, Brucepattersonius iheringi, Cryptonanus sp., Didelphis albiventris, D. aurita, Gracilinanus microtarsus, Monodelphis americana, M. scalops, Myocastor coypus, Nectomys squamipes, Oligoryzomys nigripes, Oxymycterus judex, O. nasutus, Sooretamys angouya e Thaptomys nigrita. Capturas por armadilhas de queda representaram 67% do total, e oito espécies foram registradas exclusivamente por este método. Akodon montensis, O. nigripes e T. nigrita foram as espécies mais abundantes.

  15. Cytogenetic analysis of some Brazilian marsupials (Didelphidae

    DEFF Research Database (Denmark)

    Casartelli, C; Rogatto, S R; Ferrari, I


    Three species of marsupials from the Amazon region (Marmosa cinerea, Caluromys lanatus, and Didelphis marsupialis) and two from the region of São Paulo (Didelphis marsupialis and Didelphis albiventris) were studied. The G-banding pattern of the species with 2n = 14 (M. cinerea and C. lanatus) was...

  16. New host records of Ixodes luciae (Acari: Ixodidae in the State of Para, Brazil Registros de novos hospedeiros para Ixodes luciae (Acari: Ixodidae no estado do Pará, Brasil

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    Hermes Ribeiro Luz


    Full Text Available The aim of this paper is to record new hosts for Ixodes luciae Sénevet in the State of Para, Brazil, and present a case of malformation (teratogeny in a nymph of this species. The new host records are Marmosa murina (parasitized by females and Philander opossum (parasitized by nymphs. One of these nymphs showed malformation in the posterior margin of the opisthosoma resulting in a heart shaped posterior end.O objetivo deste trabalho foi registrar novos hospedeiros para Ixodes luciae Sénevet no estado do Pará, Brasil, e um caso de malformação em uma ninfa dessa espécie de carrapato. Os novos hospedeiros são Marmosa murina (parasitado por fêmeas e Philander opossum (parasitado por ninfas. Uma dessas ninfas apresentou uma malformação na parte posterior do opistossoma em forma de coração.

  17. Karyotype composition of some rodents and marsupials from Chapada Diamantina (Bahia, Brasil

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    LG. Pereira

    Full Text Available The Chapada Diamantina (CD is located in Bahia State, between 11-14° S and 41-43° W, being part of the Serra do Espinhaço. The occurrence of different habitats and transition areas permits an interesting mammal fauna composition, with species from different biomes living in sympatry. Species of Didelphimorphia and Rodentia are important members of mammal communities in almost all different habitats, and morphological and cytogenetic characters are important for a correct identification of most of these species. In this work 258 specimens of small mammals from the orders Didelphimorphia (six genera and six species and Rodentia (two families, five Sigmodontinae tribes, nine genera and 11 species were collected during the whole field work (44 nights with traps. Chromosome preparations were obtained from 145 specimens from the species: Marmosops incanus, Gracilinanus microtarsus, Monodelphis domestica, Akodon aff. cursor, Necromys lasiurus, Cerradomys sp., Oligoryzomys fornesi, O. nigripes, O. rupestris, Calomys expulsus, Rhipidomys macrurus, Wiedomys pyrrhorhinus and Thrichomys inermis. Didelphis albiventris, Micoureus demerarae, Thylamys karymii and Nectomys sp. were identified by morphological characters. Most analyzed specimens do not show karyotype variation. However, numerical chromosomic variation was found in two individuals of Akodon aff. cursor (2n = 15 and in one individual of Cerradomys sp. (2n = 51. Structural variation in karyotype was observed in seven individuals of Cerradomys sp., showing one additional pair of metacentric chromosomes.

  18. New species and records of mites of the superfamily Sarcoptoidea (Acariformes: Psoroptidia) from mammals in Brazil. (United States)

    Bochkov, Andre V; Valim, Michel P


    Sixteen species of the superfamily Sarcoptoidea (Acariformes: Psoroptidia) belonging to 10 genera of the families Atopomelidae, Listrophoridae, Chirodiscidae, and Listropsoralgidae are recorded in Brazil. Among them, three species, Prolistrophorus hylaeamys sp. nov. from Hylaeamys laticeps (Lund, 1840) (Cricetidae: Sigmodontinae) from Minas Gerais, Lynxacarus serrafreirei sp. nov. from Galictis cuja (Molina, 1782) (Carnivora: Mustelidae) from Rio de Janeiro (Listrophoridae), and Didelphoecius micoureus sp. nov. (Atopomelidae) from Micoureus paraguayanus (Tate, 1931) (Didelphimorphia: Didelphidae) from Minas Gerais are described as new for science. Three species of the family Listrophoridae, Prolistrophorus bidentatus Fain et Lukoschus, 1984 from Akodon cursor (Winge, 1887) (Rodentia: Cricetidae) (new host), Prolistrophorus ctenomys Fain, 1970 from Ctenomys torquatus Lichtenstein, 1830 (Rodentia: Ctenomyidae) (new host), and Leporacarus sylvilagi Fain, Whitaker et Lukoschus, 1981 from Sylvilagus brasiliensis (Linnaeus, 1758) (Lagomorpha: Leporidae) (new host) -from Minas Gerais and Rio Grande do Sul, and one species of the family Chirodiscidae, Parakosa tadarida McDaniel and Lawrence, 1962 from Molossus molossus (Pallas, 1766) (Chiroptera: Molossidae) are recorded for the first time in Brazil. The previously unknown female of Didelphoecius validus Fain, Zanatta-Coutinho et Fonseca, 1996 (Atopomelidae) from Metachirus nudicaudatus (Geoffroy, 1803) (Didelphimorphia: Didelphidae) from Minas Gerais is described. All data on host-parasite associations of sarcoptoids in Brazil are summarized. Totally, 61 sarcoptoid species of 8 families are recorded in Brazil.

  19. Descriptions of diplostomid metacercariae (Digenea: Diplostomidae from freshwater fishes in the Tshwane area

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    Esmey B.E. Moema


    Full Text Available The metacercarial (larval stages of diplostomid digeneans are known to inhabit freshwater fish, causing tissue damage in the process. Due to their widespread diversity, little is known about their life cycle. The classification of these parasitic stages to the species level using only the morphology is very challenging due to the lack of genitalia; they are regarded to be the most important structures in the identification of these organisms. In this study, additional morphological information through light and scanning electron microscopy is given for two different diplostomids found in the cranial cavity of Clarias gariepinus and the vitreous chambers of Tilapia sparrmanii and Pseudocrenilabrus philander. The diplostomid metacercaria inhabiting the cranial cavity of Clarias gariepinus was morphologically identified as Diplostomulum (Tylodelphys mashonenseand an unknown metacercaria of the genus Diplostomumwas found in the vitreous chambers of Pseudocrenilabrus philander and Tilapia sparrmanii. Both parasitic species’ 28S recombinant deoxyribonucleic acid genomic regions were successfully amplified using Dig 125/1500R primer pairs. The assay yielded a product of approximately 1300 base pairs as seen on the gel images. There were 14 nucleotide differences over the entire analysed sequences resulting in a 1.1% (14/1273 nucleotide difference. In line with the morphological characteristics of these parasites, there seemed to be a slight difference in their genetic makeup. The application of molecular techniques on digenetic trematodes seems very promising and may yield great potential in future descriptions of morphologically similar parasitic species.

  20. Structural colouration of mammalian skin: convergent evolution of coherently scattering dermal collagen arrays. (United States)

    Prum, Richard O; Torres, Rodolfo H


    For more than a century, the blue structural colours of mammalian skin have been hypothesized to be produced by incoherent, Rayleigh or Tyndall scattering. We investigated the colour, anatomy, nanostructure and biophysics of structurally coloured skin from two species of primates - mandrill (Mandrillus sphinx) and vervet monkey (Cercopithecus aethiops) - and two species of marsupials - mouse opossum (Marmosa mexicana) and wooly opossum (Caluromys derbianus). We used two-dimensional (2-D) Fourier analysis of transmission electron micrographs (TEMs) of the collagen arrays in the primate tissues to test whether these structural colours are produced by incoherent or coherent scattering (i.e. constructive interference). The structural colours in Mandrillus rump and facial skin and Cercopithecus scrotum are produced by coherent scattering by quasi-ordered arrays of parallel dermal collagen fibres. The 2-D Fourier power spectra of the collagen arrays from Mandrillus and Cercopithecus reveal ring-shaped distributions of Fourier power at intermediate spatial frequencies, demonstrating a substantial nanostructure of the appropriate spatial frequency to produce the observed blue hues by coherent scattering alone. The Fourier power spectra and the observed reflectance spectra falsify assumptions and predictions of the incoherent, Rayleigh scattering hypothesis. Samples of blue Marmosa and Caluromys scrotum conform generally to the anatomy seen in Mandrillus and Cercopithecus but were not sufficiently well preserved to conduct numerical analyses. Colour-producing collagen arrays in mammals have evolved multiple times independently within the two clades of mammals known to have trichromatic colour vision. Mammalian colour-producing collagen arrays are anatomically and mechanistically identical to structures that have evolved convergently in the dermis of many lineages of birds, the tapetum of some mammals and the cornea of some fishes. These collagen arrays constitute quasi

  1. Panamanian forest mammals as carriers of Salmonella. (United States)

    Kourany, M; Bowdre, L; Herrer, A


    Enteric bacteria pathogenic to man were sought in a total of 974 forest mammals collected from a variety of sites in rural and jungle areas of Panamá. The highest incidence of infection among the mammals was observed during the Panamanian dry season, which normally extends from January through April. A minimum of 10 Salmonella serotypes including, three of the Arizona group and Ewardsiella tarda, was isolated. Opossums of the genera Philander, 11 of 54 (20.1%), and Didelphis, 12 of 102 (11.8%) demonstrated high infection rates. One sloth of the genus Choloepus and specimens of two genera of rodents also were infected to varying degrees: 1(11.1%) of 9 Choloepus, 8 (1.1%) of 704 Proechimys and 1 (16.7%) of 6 Diplomys.

  2. Euarchontan Opsin Variation Brings New Focus to Primate Origins. (United States)

    Melin, Amanda D; Wells, Konstans; Moritz, Gillian L; Kistler, Logan; Orkin, Joseph D; Timm, Robert M; Bernard, Henry; Lakim, Maklarin B; Perry, George H; Kawamura, Shoji; Dominy, Nathaniel J


    Debate on the adaptive origins of primates has long focused on the functional ecology of the primate visual system. For example, it is hypothesized that variable expression of short- (SWS1) and middle-to-long-wavelength sensitive (M/LWS) opsins, which confer color vision, can be used to infer ancestral activity patterns and therefore selective ecological pressures. A problem with this approach is that opsin gene variation is incompletely known in the grandorder Euarchonta, that is, the orders Scandentia (treeshrews), Dermoptera (colugos), and Primates. The ancestral state of primate color vision is therefore uncertain. Here, we report on the genes (OPN1SW and OPN1LW) that encode SWS1 and M/LWS opsins in seven species of treeshrew, including the sole nocturnal scandentian Ptilocercus lowii. In addition, we examined the opsin genes of the Central American woolly opossum (Caluromys derbianus), an enduring ecological analogue in the debate on primate origins. Our results indicate: 1) retention of ultraviolet (UV) visual sensitivity in C. derbianus and a shift from UV to blue spectral sensitivities at the base of Euarchonta; 2) ancient pseudogenization of OPN1SW in the ancestors of P. lowii, but a signature of purifying selection in those of C. derbianus; and, 3) the absence of OPN1LW polymorphism among diurnal treeshrews. These findings suggest functional variation in the color vision of nocturnal mammals and a distinctive visual ecology of early primates, perhaps one that demanded greater spatial resolution under light levels that could support cone-mediated color discrimination.

  3. [Diversity, natural history and conservation of mammals from San Vito de Coto Brus, Costa Rica]. (United States)

    Pacheco, Jesús; Ceballos, Gerardo; Daily, Gretchen C; Ehrlich, Paul R; Suzán, Gerardo; Rodríguez-Herrera, Bernal; Marcé, Erika


    Although Costa Rica has been biologically well studied, few areas have complete mammal inventories, which are essential for ecological studies and conservation. The San Vito region is considered among the most important for scientific research in the country because of the presence of the Wilson Botanical Garden and Las Cruces. However, the knowledge of its mammalian fauna is incomplete. We extensively studied the mammals of San Vito, compiled a checklist, and evaluated its composition, relative abundance, habitat distribution, and conservation status. We recorded 105 species, representing 85 genera, 29 families, and 10 orders. Non-volant mammals represented 62 species, 59 genera, 23 families, and 9 orders. Bats belonged to 6 families, 26 genera and 43 species. The extensive deforestation and hunting have caused the extinction of seven species, but the region still supports, surprisingly, a relatively high number of species, most of which are rare. Few species are common and abundant. Species richness was higher in forest, and forest fragments; fewer species were found in coffee plantations, induced grasslands, and secondary vegetation. Around 21% (13 species) are included in the IUCN red book. Three species are considered endangered (Saimiri oerstedii, Tapirus bairdii, and Sylvilagus dicei), and two threatened (Myrmecophaga trydactila and Caluromys derbianus), of which two (T. bairdii and M. trydactila) are locally extinct. The other species in IUCN are either of low risk (i.e. Chironectes minimus) or data deficient (Lontra longicaudis). Additionally, 24 species (39%) are included in CITES.

  4. The ecology of the Trypanosoma cruzi transmission cycle: Dispersion of zymodeme 3 (Z3) in wild hosts from Brazilian biomes. (United States)

    Lisboa, Cristiane Varella; Xavier, Samanta Cristina das Chagas; Herrera, Heitor Miraglia; Jansen, Ana Maria


    Two main genotypes in Trypanosoma cruzi subpopulations can be distinguished by PCR amplification of sequences from the mini-exon gene non-transcribed spacer, respectively, T. cruzi I (TCI) and T. cruzi II (TCII). This technique is also capable of distinguishing a third assemblage of subpopulations that do not fit in these genotypes and that remain known as zymodeme Z3 (Z3). The distribution pattern as well as the mammalian host range of this latter T. cruzi sublineage still remains unclear. Thus, the intention of our study was to increase the information regarding these aspects. The mini-exon analysis of T. cruzi isolates obtained from sylvatic animals in the Amazon Forest, Atlantic Rainforest, Caatinga and Pantanal showed that prevalence of the Z3 subpopulation in nature was low (15 out of 225 isolates, corresponding to 7%). A higher prevalence of Z3 was observed in the Caatinga (15%) and the Pantanal (12%). Infection by Z3 was observed in mammalian hosts included in Carnivora, Chiroptera, Didelphimorphia, Rodentia and Xernathra. The T. cruzi Z3 subpopulation was observed also in mixed infections (33%) with TCI (n=2) and TCII (n=3). These results demonstrate that T. cruzi Z3 displays a wider distribution and host range than formerly understood as it has been demonstrated to be able infect species included in five orders of mammalian host species dispersed through all forest strata of the four Brazilian biomes evaluated.

  5. Catalog of type specimens of recent mammals: orders Didelphimorpha through Chiroptera (Excluding Rodentia) in the National Museum of Natural History, Smithsonian Institution (United States)

    Fisher, Robert D.; Ludwig, Craig A.


    The type collection of Recent Mammals in the Division of Mammals, National Museum of Natural History, Smithsonian Institution, contains 820 specimens bearing names of 809 species-group taxa of Didelphimorphia through Chiroptera, excluding Rodentia, as of June 2014. This catalog presents an annotated list of these holdings comprised of 788 holotypes, 26 lectotypes, 11 syntypes (22 specimens), and 4 neotypes. Included are several specimens that should be in the collection but cannot be found or are now known to be in other collections. One hundred and twenty-seven of the names are new since the last type catalog covering these orders, Poole and Schantz (1942). Five specimens reported in Poole and Schantz (1942) were subsequently sent to the Vertebrate Paleontology collection and are not included here. Orders and families are ordered as in Wilson and Reeder (2005); within families, currently recognized genera are arranged alphabetically; within each currently recognized genus, accounts are arranged alphabetically by original published name. Information in each account includes original name and abbreviated citation thereto, current name if other than original, citation for first use of current name combination for the taxon (or new name combination if used herein for the first time), type designation, U.S. National Museum catalog number(s), preparation, age and sex, date of collection and collector, original collector number, type locality, and remarks as appropriate. Digital photographs of each specimen will serve as a condition report and will be attached to each electronic specimen record.

  6. Trypanosoma cruzi and Leishmania infantum chagasi Infection in Wild Mammals from Maranhão State, Brazil. (United States)

    da Costa, Andréa Pereira; Costa, Francisco Borges; Soares, Herbert Sousa; Ramirez, Diego Garcia; Mesquita, Eric Takashi Kamakura de Carvalho; Gennari, Solange Maria; Marcili, Arlei


    Trypanosoma and Leishmania are obligate parasites that cause important diseases in human and domestic animals. Wild mammals are the natural reservoirs of these parasites, which are transmitted by hematophagous arthropods. The present study aimed to detect the natural occurrence of trypanosomatids through serological diagnosis, PCR of whole blood and blood culture (hemoculture), and phylogenetic relationships using small subunit ribosomal DNA (SSU rDNA), cytochrome b, and glycosomal glyceraldehyde 3-phosphate dehydrogenase (gGAPDH) genes. Samples from 131 wild animals, including rodents, marsupials, and bats, were sampled in six areas in the state of Maranhão, in a transition zone of semiarid climates northeast of the equatorial humid Amazon. Serological analysis for Leishmania (Leishmania) infantum chagasi was performed in opossums by indirect fluorescent antibody test (IFAT), and all animals were serologically negative. Nine positive hemocultures (6.77%) were isolated and cryopreserved and from mammals of the Didelphimorphia and Chiroptera orders and positioned in phylogenies on the basis of sequences from different genes with reference strains of Trypanosoma cruzi marinkellei and T. cruzi. From primary samples (blood and tissues) only one bat, Pteronotus parnellii, was positive to SSU rDNA and gGAPDH genes and grouped with the L. infantum chagasi branch. The studies conducted in Maranhão State provide knowledge of parasite diversity. It is important to determine the presence of trypanosomatids in wild mammals with synanthropic habits.

  7. Checklist of helminths found in Patagonian wild mammals. (United States)

    Fugassa, Martin H


    Using available reports, a checklist of the recorded helminth parasites of wild mammals from Patagonia was generated. Records of parasites found in Patagonia were included, together with records from mammals in áreas outside of Patagonia but whose range extends into Patagonia. Information about the host, localities, and references were also included. A total of 1323 records (224 Cestoda, 167 Trematoda, 894 Nematoda, 34 Acanthocephala, and 4 Pentastomida) belonging to 452 helminth species (77 Cestoda, 76 Trematoda, 277 Nematoda, 21 Acanthocephala, and 1 Pentastomida) found in 57 native mammals (22 Rodentia, 4 Didelphimorphia 1 Microbiotheria, 7 Chiroptera, 5 Cingulata, and 13 Carnivora) were listed. However, only 10.6 % of the reports were conducted on samples from Patagonia and corresponded to 25% of mammals in the region. In addition, many studies were made on a few species and, for example, 52% corresponded to studies made on Lama guanicoe. This suggests the need to increase efforts to know the parasitic fauna in a peculiar region as is the Patagonia. This is the first compilation of the helminth parasites of mammals in Argentine Patagonia and is important for parasitological and paleoparasitological studies.

  8. Epidemiology of leptospirosis at Sorocaba Zoo, São Paulo state, Southeastern Brazil

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    Leila S. Ullmann


    Full Text Available Leptospirosis is considered a worldwide distributed zoonosis, caused by the bacteria Leptospira spp. Since several species of wildlife animals are reportedly reservoirs, the aim of the present study was to know the epidemiology of leptospirosis at the Sorocaba Zoo, Southern Brazil. Serum samples of wild mammals from Artiodactyla, Carnivora, Didelphimorphia, Diprotodontia, Perissodactyla, Pilosa, Primates, Proboscidea and Rodentia orders, kept in captivity as well as from zoological staff were assayed by microscopic agglutination test (MAT. Whole blood, urine and tissue samples from wild mammals and synanthropic animals were assayed by polymerase chain reaction (PCR. An epidemiological survey was applied to evaluate the risk factors for animal infection and staff level of knowledge on leptospirosis. A total of 13/229 (5.68%; CI95% 3.37-9.47% serum samples from wild mammals were reagent on MAT. Serology from synanthropic animals, zoo staff and molecular analysis of animal samples were all negative. Leptospirosis knowledge of zoo park staff was considered medium. In conclusion, leptospiral infection occurs at the studied zoo but due to the low occurrence found, the lowest reported in literature, wild captive mammals do not act as source of infection of leptospirosis to other animals and human beings.

  9. Tripanosomiasis americana: determinación de riesgo epidemiológico de transmisión en el municipio de Amalfi, Antioquia American trypanosamiasis: determination of epidemiologic transmission risk in Amalfi, Antioquia, Colombia

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    John Jairo Arboleda


    Full Text Available Se presenta por primera vez en antioquia un estudio sobre la enfermedad de Chagas, en el cual se evaluaron simultáneamente los tres componentes fundamentales de esta parasitosis: vector, parásito y reservorio. Se evaluaron 640 domicilios en 9 veredas del municipio de Amalfi, se capturaron 196 triatominos, pertenecientes a las especies Panstrongylus geniculatus (49%, P. rufotuberculatus (47%, Triatoma dispar (3% y Rhodnius pallescens (0.5%. En total se capturaron 33 animales silvestres, pertenecientes a las especies Didelphis marsupialis (8, Marmosa robinsoni (1, Hoplomys gimnurus (3, Dasypus novemcinctus (2, Proechymis sp (13, Oryzomis sp (3, Philander opossum (3, así como 63 perros (Canis lupus. Los indicadores de riesgo de transmisión de Tripanosoma cruzi por triatominos, fueron: dispersión (100%, infestación domiciliaria (14,5%, densidad (30,5%, hacinamiento (204,2% e infección relativa (12,5%. Se obtuvo una alta prevalencia de anticuerpos en los perros de las veredas Montebello (61.1% y La Gardenia (70.0% y serología positiva en un humano adulto. In this paper we report the first Chagas disease study in Antioquia-Colombia, in which the main components of this disease were simultaneously evaluated: vector, parasite and host. Field studies were carried out evaluating 640 houses in nine localities from the municipality of Amalfi; 196 triatomine bugs were captured: Panstrongylus geniculatus (49%, Panstrongylus rufotuberculatus (47%, Triatoma dispar (3% and Rhodnius pallescens (0.5%. Thirty three wild animals were captured: Didelphis marsupialis (8, Marmosa robinsoni (1, Hoplomys gimnurus (3, Dasypus novemcinctus (2, Proechymis sp (13, Oryzomis sp (3, Philander opossum (3 as well as 63 dogs (Canis lupus. Transmission risk indicators for Trypanosoma cruzi were: Dispersion (100%, Domiciliary infestation (14,5%, Insect density (30,5%, crowding (204,2% and Relative infection (12,5%. Of the nine localities studied, Montebello (61.1% and La

  10. A field comparison of two capture-mark-recapture estimators of small mammal populations

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    Rosana Gentile


    Full Text Available The results obtained by two estimators of population sizes, MNKA and Mh, were compared for four species of small mammmals - Didelphis aurita Wied, 1826, Philander frenata (Olfers, 1818, Nectomys squamipes (Brants, 1827 and Akodon cursor (Winge, 1887 - during a long-term population study. The MNKA estimator consistently underestimated the population sizes in relation to Mh. On the other, the probabilistic estimator Mh, which reduces bias through the jackknife technique, could not be used in all cases as its assumptions were not always met. Correction factors between the estimates obtained by the two methods were calculated for the last three species, for which catchability did not vary significantly in time and that presented positive correlation between the estimates by the two models. In order to combine the adavantages of both methods for small mammal population studies, is suggested the use of probabilistic closed population models and to calculate a correction factor based in another model which allow estimates in all cases, and which provides correlated estimates. This correction factors should be used in those cases where the probabilistic model cannot be used.

  11. Small mammal populations of an agroecosystem in the Atlantic Forest domain, southeastern Brazil

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    PS. D’Andrea

    Full Text Available This study reports 2 years of the population dynamics and reproduction of a small mammal community using the removal method. The study was conducted in a rural area of the Atlantic Forest, in Sumidouro, Rio de Janeiro State, Brazil. The population sizes, age structure and reproduction were studied for the four most common species in the study area. The overall diversity was 1.67 and ranged between 0.8 to 1.67. The species richness was 13 considering the whole study. The most abundant species were the rodents Nectomys squamipes (n = 133, Akodon cursor (n = 74, Oligoryzomys nigripes (n = 25 and the marsupials Didelphis aurita (n = 58 and Philander frenatus (n = 50. Seven other rodents were captured once: Necromys lasiurus, Akodon montensis, Sooretamys angouya, Oecomys catherine, Oxymycterus judex, Euryzygomatomys spinosus and Trinomys iheringi. There were higher peaks for diversity and species richness during the winter (dry months, probably due to higher food availability. The marsupials had a seasonal reproduction with highest population sizes at the end of the rainy seasons. Nectomys squamipes reproduced mostly during rainy periods. Akodon cursor reproduced predominantly in the winter with the highest population peaks occurring during this season. The analysis of the population dynamics of the rodent species indicated that no species behaved as an agricultural pest, probably due to the heterogeneous landscape of high rotativity of vegetable cultivation. Rodent populations were more susceptible to the removal procedure than marsupial ones.

  12. Small mammal populations of an agroecosystem in the Atlantic Forest domain, southeastern Brazil. (United States)

    D'Andrea, P S; Gentile, R; Maroja, L S; Fernandes, F A; Coura, R; Cerqueira, R


    This study reports 2 years of the population dynamics and reproduction of a small mammal community using the removal method. The study was conducted in a rural area of the Atlantic Forest, in Sumidouro, Rio de Janeiro State, Brazil. The population sizes, age structure and reproduction were studied for the four most common species in the study area. The overall diversity was 1.67 and ranged between 0.8 to 1.67. The species richness was 13 considering the whole study. The most abundant species were the rodents Nectomys squamipes (n = 133), Akodon cursor (n = 74), Oligoryzomys nigripes (n = 25) and the marsupials Didelphis aurita (n = 58) and Philander frenatus (n = 50). Seven other rodents were captured once: Necromys lasiurus, Akodon montensis, Sooretamys angouya, Oecomys catherine, Oxymycterus judex, Euryzygomatomys spinosus and Trinomys iheringi. There were higher peaks for diversity and species richness during the winter (dry) months, probably due to higher food availability. The marsupials had a seasonal reproduction with highest population sizes at the end of the rainy seasons. Nectomys squamipes reproduced mostly during rainy periods. Akodon cursor reproduced predominantly in the winter with the highest population peaks occurring during this season. The analysis of the population dynamics of the rodent species indicated that no species behaved as an agricultural pest, probably due to the heterogeneous landscape of high rotativity of vegetable cultivation. Rodent populations were more susceptible to the removal procedure than marsupial ones.

  13. Nematode parasites of marsupials and small rodents from the Brazilian Atlantic Forest in the State of Rio de Janeiro, Brazil

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    Delir Corrêa Gomes


    Full Text Available Nematodes from opossums and rodents captured in the Brazilian Atlantic Forest in the State of Rio de Janeiro, Brazil were studied. From the opossums Didelphis aurita Weid-Neuweid, 1826 and Philander opossum (Linnaeus, 1758 the following nematode species were recovered: Viannaia hamata Travassos, 1914, Aspidodera raillieti Travassos, 1913, Cruzia tentaculata (Rudolphi, 1819, Travassos, 1917, Turgida turgida (Rudolphi, 1819 Travassos, 1919, Gongylonemoides marsupialis (Vaz & Pereira, 1934 Freitas & Lent, 1937, Viannaia viannai Travassos, 1914, Spirura guianensis (Ortlepp, 1924 Chitwood, 1938 and from the rodents Akodon cursor (Winger, 1887, Nectomys squamipes (Brants, 1827, Oligoryzomys eliurus (Wagner, 1845 and Oryzomys intermedius (Leche, 1886: Hassalstrongylus epsilon (Travassos, 1937 Durette-Desset, 1971, Syphacia obvelata (Rudolphi, 1802 Seurat, 1916, S. venteli Travassos, 1937, Physaloptera bispiculata Vaz & Pereira, 1935, Litomosoides carinii (Travassos, 1919 Vaz, 1934, Viannaia viannai, Hassalstrongylus epsilon, H. zeta (Travassos, 1937 Durette-Desset, 1971, Stilestrongylus aculeata (Travassos, 1918 Durette-Desset, 1971 S. eta (Travassos, 1937 Durette-Desset, 1971. Highest worm burdens and prevalences were those related to Cruzia tentaculata in marsupials. Stilestrongylus aculeata was referred for the first time in Akodon cursor.

  14. Cine Club

    CERN Multimedia

    Ciné Club


    Wednesday 29 June 2011 at 20:30 CERN Council Chamber Arizona Dream  By/de : Emir Kusturica (USA/France, 1993) 142 min With/avec: Johnny Depp, Jerry Lewis, Fay Dunaway, Lily Taylor, Vincent Gallo A romantic comedy about the adventures of an innocent dreamer in the weird and colourful landscape of the American West. Caught between childhood and adulthood he finds himself back in his hometown where he becomes involved with a wealthy widow and her stepdaughter. Original version english; english subtitles Entrance : 2 CHF Projection from DVD     Thursday 7 July 2011 at 20:30 CERN Council Chamber Burn After Reading  By/de : Ethan Coen and Joel Coen (USA/UK/France, 2008) 102 min With/avec: George Clooney, Frances McDormand, Brad Pitt, John Malkovich, Tilda Swinton Osbourne Cox, a Balkan expert, is fired at the CIA, so he begins a memoir. His wife wants a divorce and expects her lover, Harry, a philandering State Dep...

  15. The Role of Solar Eclipses in El Nino/La Nina Events (United States)

    Chiu, B. C.


    The first hint of the fact that solar eclipses mark the enhanced storms called El Nino or La Nina, came from the article by Robert Allan on analysis of frequencies of these events (2001, perhaps Fourier analysis). One mystery was the cause of a cycle with period 15 to 20 years. But the Saros Series of solar eclipses has a period of 18+ years. Then we had the data from Galapagos Islands for the whole 20th century (Philander 2004). The graph of high and low temperatures indicates El Ninos and La Ninas. A search through charts of solar eclipses for those with good locations for bringing high tides at the Tropics, gave a good picture: those at the eastern coast of the pacific Ocean gave El Ninos, and those at the west gave La Ninas. More than half of the peaks and troughs on the temperature graph can be identified with solar eclipses. We looked more closely at a few events that caused great storms. They are described in J. M. Nash's book, ``El Nino" (2002). The most striking case is that of the 1998 Feb. 22 solar eclipse, which corresponds to the so-called El Nino of 1997-98. In conclusion, I would say that the annual El nino effect is due to the sun's travel between the Tropic of Cancer and Tropic of Capricorn. But the enhanced El Niino/La Nina is due to the coming together of sun and moon in the solar eclipses, which seem to come irregularly.

  16. Micromamiferos andinos holocenicos del sitio arqueologico Inca Cueva 5, Ju Juy, Argentina: tafonomia, zoogeografia y reconstruccion paleoambiental

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    Ortiz, P. E.


    Full Text Available A micromammal archaeological sequence (2120 f 120 to 780 f 100 years BP from Inca Cueva 5 site (23" 05' S - 65" 27' W; 3700 m.a.s.l., Jujuy Province, Argentina was studied. The following mammalian taxa were recorded: Order Didelphimorphia, Family Didelphidae, Thylamys cf. T. pallidior; Order Rodentia, Family Muridae, Akodon cf. A. albiventer, Andinomys edax, Auliscomys sublimis, Calomys lepidus, Neotomys ebriosus, Phyllotis sp.; Family Caviidae, Cavia cf. C. tschudii, Galea musteloides; Family Abrocomidae, Abrocoma cinerea; Family Chinchillidae, Lagidium viscacia; Family Octodontidae, Octodontomys gliroides. The taphonomy indicates that the sequence is an owl pellet accumulation inside the cave. The general landscape corresponds to the oriental border of the Puna steppe, with scattered shrub and low brush vegetation. Near the site there are small tree groups of Polylepis australis as well as small streams covered with grass and ciperaceous vegetation known as «vegas». Al1 the recorded taxa at Inca Cueva 5 exist today in Puna and Prepuna environments from Jujuy and Salta Provinces and southem Bolivia, excepting Cavia cf. C. tschudii. The modem records of this species in northem Argentina and southern Bolivia come from localities with high montane bunchgrass prairies and forests of the humid Yungas phytogeographical region. The presence of this species in the sequence suggests wetter climatic conditions on this region when the archaeological site was originated. Later drier conditions, caused probably by anthropic influence in the last 500 years, produced the retraction of Cavia tschudii to the moist eastern side of the Andes and its disappeareance of the Puna areas.El sitio arqueológico Inca Cueva 5 se encuentra en la provincia de Jujuy, Argentina, en el borde oriental de la región de la Puna (23" 05' S - 65" 27' W; 3700 m s n m y está fechado entre 2120 f 120 y 780 f 100 años radiocarbónicos AP. El estudio de una pequeña muestra de

  17. Dental anomalies in Didelphis albiventris (Mammalia, Marsupialia, Didelphidae from Argentina, Brazil and Uruguay

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    M. Amelia Chemisquy

    Full Text Available ABSTRACT Dental anomalies have been investigated and reported for most orders of mammals, including marsupials. Previous works in Didelphis albiventris Lund, 1840 only described one kind of malformation or just a few observations from some collections, thus the type and presence of anomalies for this species was underestimated. The aim of this contribution is to describe and analyze several dental anomalies found in specimens of Didelphis albiventris from Argentina, Uruguay and Brazil. Dental anomalies were classified in three categories: supernumerary or missing teeth, morphological anomalies in size and shape, and teeth in unusual positions. We found 32 individuals of D. albiventris with anomalies out of 393 analyzed specimens (8.14%, some specimens with more than one anomaly. A similar proportion of specimens from Argentina and Uruguay presented anomalies, while in specimens from Brazil anomalies were less common. Anomalies were more commonly found in the upper toothrow and in molars, being supernumerary teeth and molars with unusual crown-shape the most common ones. The percentage of specimens with anomalies found for D. albiventris is higher than previously reported for the species, and other Didelphimorphia. Inbreeding and limited gene flow do not appear as possible explanations for the elevated percentage of anomalies, especially due to the ecological characteristics of Didelphis albiventris. Developmental instability and fluctuating asymmetry could be some of the causes for the anomalies found in this species, mostly since the habitat used by D. albiventris tends to be unstable and disturbed. Dental anomalies were mostly found in areas of the toothrow where occlusion is relaxed or does not prevent teeth from interlocking during mastication, and consequently have no functional value.

  18. Diet of margay, Leopardus wiedii, and jaguarundi, Puma yagouaroundi, (Carnivora: Felidae in Atlantic Rainforest, Brazil

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    Rita de Cassia Bianchi


    Full Text Available This study identifies the food habits of the margay, Leopardus wiedii (Schinz, 1821, and the jaguarundi, Puma yagouaroundi (É. Geoffroy Saint-Hilare, 1803, in the Vale do Rio Doce Natural Reserve and in the Sooretama Biological Reserve, Espírito Santo, Brazil. We determined the diet of both species by the analysis of scats. Fecal samples were collected from April 1995 to September 2000 and identified based on the presence of hairs that were ingested during self-grooming. Scats were oven-dried and washed on a sieve, and the screened material was identified using a reference collection. Of the 59 fecal samples examined, 30 were confirmed to be from the margay and nine of them from the jaguarundi. Mammals were the most consumed items in the diet of the margay, occurring in 77% of the fecal samples, followed by birds (53% and reptiles (20%. Among the mammals consumed, marsupials (Didelphimorphia were the most common item (66%. In the diet of the jaguarundi, birds were the most consumed items and occurred in 55% of the fecal samples; mammals and reptiles occurred in 41% and in 17% of the fecal samples, respectively. From this work we conclude that the margay and jaguarundi fed mainly upon small vertebrates in the Vale do Rio Doce Natural Reserve and in the Sooretama Biological Reserve. Although sample sizes are therefore insufficient for quantitative comparisons, margays prey more frequently upon arboricolous mammals than jaguarundis, which in turn prey more frequently upon birds and reptiles than margays. This seems to reflect a larger pattern throughout their geographic range

  19. Threat diversity will erode mammalian phylogenetic diversity in the near future.

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    Clémentine M A Jono

    Full Text Available To reduce the accelerating rate of phylogenetic diversity loss, many studies have searched for mechanisms that could explain why certain species are at risk, whereas others are not. In particular, it has been demonstrated that species might be affected by both extrinsic threat factors as well as intrinsic biological traits that could render a species more sensitive to extinction; here, we focus on extrinsic factors. Recently, the International Union for Conservation of Nature developed a new classification of threat types, including climate change, urbanization, pollution, agriculture and aquaculture, and harvesting/hunting. We have used this new classification to analyze two main factors that could explain the expected future loss of mammalian phylogenetic diversity: 1. differences in the type of threats that affect mammals and 2. differences in the number of major threats that accumulate for a single species. Our results showed that Cetartiodactyla, Diprotodontia, Monotremata, Perissodactyla, Primates, and Proboscidea could lose a high proportion of their current phylogenetic diversity in the coming decades. In contrast, Chiroptera, Didelphimorphia, and Rodentia could lose less phylogenetic diversity than expected if extinctions were random. Some mammalian clades, including Marsupiala, Chiroptera, and a subclade of Primates, are affected by particular threat types, most likely due solely to their geographic locations and associations with particular habitats. However, regardless of the geography, habitat, and taxon considered, it is not the threat type, but the threat diversity that determines the extinction risk for species and clades. Thus, some mammals might be randomly located in areas subjected to a large diversity of threats; they might also accumulate detrimental traits that render them sensitive to different threats, which is a characteristic that could be associated with large body size. Any action reducing threat diversity is

  20. A radio tracking study of home range and movements of the marsupial Micoureus demerarae (Thomas (Mammalia, Didelphidae in the Atlantic forest of south-eastern Brazil

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    Edsel Amorim Moraes Junior


    Full Text Available From August 2001 to July 2002 the home range and movements of seven Micoureus demerarae (Thomas, 1905 (three males and four females were investigated using radio tracking in the União Biological Reserve, state of Rio de Janeiro, south-eastern Brazil. A total of 436 locations was obtained and home range estimated with fixed Kernel (95% of data points, and minimum convex polygon (MCP methods, with 100 and 95% of data points. Male home ranges estimated by MCP (100% ranged from 5.4-24.2 ha and females from 0.3-10.7 ha. Corresponding figures calculated with Kernel (95% were 4-10.9 ha for males and 1.3-5.9 ha for females. Animals travelled on average 423 m/night, with males travelling significantly further (582.8 m/night than females (335.1 m/night (t test, t = 3.609, p = 0.001. We concluded that radio tracking produced much larger home ranges than those estimated with traditional live-trapping techniques, suggesting that the latter might underestimate ranging when the area covered with traps is relatively small (ca. 1 ha or less. Radio tracking also indicated that M. demerarae, although predominantly arboreal and weighting only ca. 130 g., has movements similar in magnitude to larger-sized terrestrial didelphimorph marsupials, such as Didelphis Linnaeus, 1758, Philander Linnaeus, 1758 and Metachirus (Desmarest, 1817.No período de agosto de 2001 a julho de 2002 a área de uso e o movimento de sete Micoureus demerarae (Thomas, 1905 (três machos e quatro fêmeas foram acompanhados, através de rádio-telemetria, na Reserva Biológica União, Rio de Janeiro, sudeste do Brasil. Foi obtido um total de 436 localizações e estimou-se a área de uso através dos métodos Kernel fixo (95% das localizações e polígono mínimo convexo (PMC, com 100 e 95% das localizações. A área de uso dos machos estimada pelo PMC (100% variou de 5,4-24,2 ha e fêmeas de 0,3-10,7 ha. Áreas calculadas com Kernel (95% foram 4-10,9 ha para machos e 1,3-5,9 ha para f

  1. Ocean Color and the Equatorial Annual Cycle in the Pacific (United States)

    Hammann, A. C.; Gnanadesikan, A.


    upwelling acting on a mean temperature field contribute the largest term to SST variability (Köberle & Philander 1994; Li & Philander 1996). We examine whether it is changes in the surface currents (driven by the annual cycle of winds) or changes in the mean temperature fields (driven by enhanced penetration of solar radiation) that drive the differences between the coupled models. We do this using a simple linear equatorial-wave model, which, when forced with an annual harmonic of wind stresses, reproduces the essential characteristics of annual ocean current anomalies. The model solves the linearized Boussinesq equations by expansion into discrete modes in all spatial dimensions (McCreary 1981; Lighthill 1969). Both the wind forcing and the (laterally homogeneous) background density profile are constructed as approximations to the coupled model fields. The annual perturbation currents from the wave model are then used to advect the mean temperature fields from the coupled model experiments. While the difference in the mean stratification explains the difference between the 'green' and 'blue' cases. For the other two cases, it appears that changes in the annual wind fields need also be taken into account. An initial hypothesis is that the hemispheric asymmetry in the annual amplitude of wind stress curl that is most important in setting the amplitude of the annual cycle on the equator.

  2. [Trypanosoma cruzi in French Guinea: review of accumulated data since 1940]. (United States)

    Raccurt, C P


    Between 1939 and 1994, nine cases of Chagas disease have been reported in French Guiana: seven in the acute phase including two that were fatal and two in the chronic phase with cardiac sequellae. A tenth case of transient parasitemia was described but the patient's clinical status was not mentioned. Screening by xenodiagnosis revealed one subclinical infection. Heart disease is a highly specific manifestation of Trypanosoma cruzi infection, this being consistent with the known presence of zymodeme 1 in the sylvatic reservoir and reduviid vectors. The low incidence of positive serology (0.7% in a group of 740 subjects in whom serum samples were tested by indirect immunofluorescence) indicates that the disease is not currently becoming endemic. The main animal reservoirs for infection are small land marsupials (Didelphis marsupialis being the most frequently infected) and edentata especially armadillos (Dasypus novemcinctus). A peridomestic cycle, implicating D. marsupialis and Philander oppossum, plant-eating marsupials, with Rhodnius pictipes as the vector is highly active. Further study is necessary to ascertain another mechanism involving R. prolixus as a vector in dwellings in urban areas. Outbreaks require careful epidemiologic surveillance. French Guiana should no longer be considered as an enzootic area but as an area of risk for sporadic Chagas disease with epidemiologic features similar to those of the disease in dense Amazon forest areas. Appropriate measures must be taken to screen and promptly manage Chagas disease in the population. Special care is needed for concurrent HIV-T. cruzi infection due to the severity of this combination. Preventive measures are also needed to preclude transfusional infection.

  3. Mesoscale eddies over the Laptev Sea continental slope in the Arctic Ocean (United States)

    Pnyushkov, A.; Polyakov, I.; Nguyen, A. T.


    Mesoscale eddies are an important component in Arctic Ocean dynamics and can play a role in vertical redistribution of ocean heat from the intermediate layer of warm Atlantic Water (AW). We analyze mooring data collected along the continental slope of the Laptev Sea in 2007-11 to improve the characterization of Arctic mesoscale eddies in this region of the Eurasian Basin (EB).Wavelet analyses suggest that ~20% of the mooring record is occupied by mesoscale eddies, whose vertical scales can be large, often >600 m. Based on similarity between temperature/salinity profiles measured inside eddies and modern climatology for the 2000s, we found two distinct sources of eddy formation in the EB; one in the vicinity of Fram Strait and the other at the continental slope of the Severnaya Zemlya Archipelago. Both sources of eddies are on the route of AW propagation along the EB margins, so that the Arctic Circumpolar Boundary Current (ACBC) can carry these eddies along the continental slope.The lateral advection of waters isolated inside the eddy cores by ACBC affect the heat and salt balance of the eastern EB. The average temperature anomaly inside Fram Strait eddies in the layer above the AW temperature core (i.e., above 350 m depth level) was ~0.1º C with the strongest temperature anomaly in this layer exceeding 0.5ºC. In contrast to Fram Strait eddies, Severnaya Zemlya eddies carry anomalously cold and fresh water, and likely contribute to ventilation of the AW core. In addition, we found increased vertical shears of the horizontal velocities inside eddies that result in enhanced mixing. Our estimates made using the Pacanowski and Philander (1981) relationship suggest that, on average, vertical diffusivity coefficients inside eddies are four times larger than those in the surrounding waters. We will use the high resolution ECCO model to investigate the relative contributions of along and across slope transports induced by eddies along the ACBC path.

  4. Serologic evidence of canine parvovirus in domestic dogs, wild carnivores, and marsupials in the Argentinean Chaco. (United States)

    Orozco, María Marcela; Miccio, Luciano; Enriquez, Gustavo Fabián; Iribarren, Fabián Eduardo; Gürtler, Ricardo Esteban


    The transmission of pathogens between domestic dogs and generalist wildlife species may be modified by environmental degradation, biodiversity losses, host densities, and increased contact rates in remnant forest patches. A serologic survey of canine parvovirus (CPV) in rural domestic dogs and wild mammals was conducted in two neighboring rural areas (disturbed and protected) from Pampa del Indio, northeastern Argentina, between 2008 and 2011. A total of 174 domestic dogs and 26 wild mammals-4 crab-eating foxes (Cerdocyon thous), 3 crab-eating raccoons (Procyon cancrivorus), 17 white-eared opossums (Didelphis albiventris), and 2 gray four-eyed opossums (Philander opossum)-were examined for antibodies to CPV using a hemagglutination inhibition assay. Domestic dogs were numerous and their movements unrestricted. The main function of dogs differed significantly between areas, with more dogs used for herding or hunting around the protected area. The seroprevalence of antibodies to CPV in dogs from both areas was very high (93.9-94.6%) and increased steeply with age. Nearly all carnivores and marsupials showed high exposure to CPV. Although a higher exposure to CPV was expected in wild mammals from disturbed areas as a result of enhanced contact between dogs and wildlife, no significant differences were found between areas. To the authors' knowledge, this study is the first to document exposure to CPV of free-ranging Pr. cancrivorus, D. albiventris, and Ph. opossum, and include a detailed demographic study of the domestic dog populations living in the area. This study highlights that dogs and wildlife have potential opportunities for contact and shows that the edges of the protected area may be as suitable as other fragmented areas for the transmission of CPV. Rural domestic dogs may pose serious threats to the health and conservation of wild carnivores in both disturbed and protected areas, especially in the Gran Chaco, where habitat fragmentation is severely

  5. Myosin isoform expression in the prehensile tails of didelphid marsupials: functional differences between arboreal and terrestrial opossums. (United States)

    Rupert, J E; Schmidt, E Cordero; Moreira-Soto, A; Herrera, B Rodríguez; Vandeberg, J L; Butcher, M T


    Prehensile tails are defined as having the ability to grasp objects and are commonly used as a fifth appendage during arboreal locomotion. Despite the independent evolution of tail prehensility in numerous mammalian genera, data relating muscle structure, physiology, and function of prehensile tails are largely incomplete. Didelphid marsupials make an excellent model to relate myosin heavy chain (MHC) isoform fiber type with structure/function of caudal muscles, as all opossums have a prehensile tail and tail use varies between arboreal and terrestrial forms. Expanding on our previous work in the Virginia opossum, this study tests the hypothesis that arboreal and terrestrial opossums differentially express faster versus slower MHC isoforms, respectively. MHC isoform expression and percent fiber type distribution were determined in the flexor caudae longus (FCL) muscle of Caluromys derbianus (arboreal) and Monodelphis domestica (terrestrial), using a combination of gel electrophoresis and immunohistochemistry analyses. C. derbianus expresses three MHC isoforms (1, 2A, 2X) that are distributed (mean percentage) as 8.2% MHC-1, 2.6% 1/2A, and 89.2% 2A/X hybrid fibers. M. domestica also expresses MHC-1, 2A, and 2X, in addition to the 2B isoform, distributed as 17.0% MHC-1, 1.3% 1/2A, 9.0% 2A, 75.2% 2A/X, and 0.3% 2X/B hybrid fibers. The distribution of similar isoform fiber types differed significantly between species (P derbianus was observed to have larger cross-sectional area (CSA) for each corresponding fiber type along with a greater amount of extra-cellular matrix. An overall faster fiber type composition (and larger fibers) in the tail of an arboreal specialist supports our hypothesis, and correlates with higher muscle force required for tail hanging and arboreal maneuvering on terminal substrates. Conversely, a broader distribution of highly oxidative fibers in the caudal musculature is well suited for tail nest building/remodeling behaviors of terrestrial

  6. Diversity and Impacts of Mining on the Non-Volant Small Mammal Communities of Two Vegetation Types in the Brazilian Amazon (United States)

    Ardente, Natália Carneiro; Ferreguetti, Átilla Colombo; Gettinger, Donald; Leal, Pricila; Mendes-Oliveira, Ana Cristina; Martins-Hatano, Fernanda; Bergallo, Helena Godoy


    The Carajás National Forest contains some of the largest iron ore deposits in the world. The majority of the minerals are found below a plant community known as Savana Metalófila, or “Canga”, which represents only 3% of the landscape within the Carajás National Forest (CNF). The aim of our study was to understand the diversity of community of non-volant small mammals in the two predominant vegetation types: Ombrophilous Forest and Canga, and to examine how mining impacts these communities. Sampling was conducted from January 2010 to August 2011 in 11 sampling sites divided by the total area of Canga and 12 sampling sites in the forest, totalizing 23 sites. Of these, 12 sites (Canga and Forest) were considered impacted areas located close to the mine (<< 900 meters) and 11 sites (Canga and Forest), serving as controls, which were at least 7,000 meters from the mine. We recorded 28 species, 11 from the Order Didelphimorphia and 17 from the Order Rodentia. The two forest types shared 68.42% of the species found in the CNF. A gradient analysis (Non-metric multidimensional scaling) revealed that the first axis clearly separated the non-flying small mammal communities by vegetation type. Occupancy models showed that the detectability of species was affected by the distance from the mining activities. Of all the small mammals analyzed, 10 species were positively affected by the distance from mining in areas impacted (e.g. more likely to be detected farther from mining areas) and detectability was lower in impacted areas. However, three species were negatively affected by the distance from mining, with higher detectability in the impacted areas, and seven species showed no effect of their proximity to mining operations. To date, there are no studies in Brazil about the impact of mining on mammals or other vertebrates. This study reveals that the effect of mining may go beyond the forest destruction caused by the opening of the mining pits, but also may negatively

  7. Offspring mortality was a determinant factor in the evolution of paternal investment in humans: An evolutionary game approach. (United States)

    López Alonso, Diego; Ortiz-Rodríguez, Isabel M


    Some researchers support the belief that man evolved philandering behavior because of the greater reproductive success of promiscuous males. According to this idea, deserting behavior from the man should be expected along with null paternal involvement in offspring care. Paradoxically however, the average offspring investment in the human male is far higher than that of any other male mammal, including other primates. In our work, we have addressed this conundrum by employing evolutionary game theory, using objective payoffs instead of, as are commonly used, arbitrary payoffs. Payoffs were computed as reproductive successes by a model based on trivial probabilities, implemented within the Barreto's Population Dynamics Toolbox (2014). The evolution of the parent conflict was simulated by a game with two players (the woman and the man). First, a simple game was assayed with two strategies, 'desert-unfaithful' and 'care-faithful'. Then, the game was played with a third mixed strategy, 'care-unfaithful'. The two-strategy game results were mainly determined by the offspring survival rate (s) and the non-paternity rate (z), with remaining factors playing a secondary role. Starting from two empirical estimates for both rates (s = 0.617 and z = 0.033) and decreasing the offspring mortality from near 0.4 to 0.1, the results were consistent with a win for the 'care-faithful' strategy. The 'desert-unfaithful' strategy only won at unrealistically high non-paternity rates (z>0.2). When three-strategy games were played, the mixed strategy of 'care-unfaithful' man could win the game in some less frequent cases. Regardless of the number of game strategies, 'care' fathers always won. These results strongly suggest that offspring mortality was the key factor in the evolution of paternal investment within the Homo branch. The 'care-faithful' strategy would have been the main strategy in human evolution but 'care-unfaithful' men did evolve at a lesser frequency. It can therefore be

  8. Mixing parametrizations for ocean climate modelling (United States)

    Gusev, Anatoly; Moshonkin, Sergey; Diansky, Nikolay; Zalesny, Vladimir


    The algorithm is presented of splitting the total evolutionary equations for the turbulence kinetic energy (TKE) and turbulence dissipation frequency (TDF), which is used to parameterize the viscosity and diffusion coefficients in ocean circulation models. The turbulence model equations are split into the stages of transport-diffusion and generation-dissipation. For the generation-dissipation stage, the following schemes are implemented: the explicit-implicit numerical scheme, analytical solution and the asymptotic behavior of the analytical solutions. The experiments were performed with different mixing parameterizations for the modelling of Arctic and the Atlantic climate decadal variability with the eddy-permitting circulation model INMOM (Institute of Numerical Mathematics Ocean Model) using vertical grid refinement in the zone of fully developed turbulence. The proposed model with the split equations for turbulence characteristics is similar to the contemporary differential turbulence models, concerning the physical formulations. At the same time, its algorithm has high enough computational efficiency. Parameterizations with using the split turbulence model make it possible to obtain more adequate structure of temperature and salinity at decadal timescales, compared to the simpler Pacanowski-Philander (PP) turbulence parameterization. Parameterizations with using analytical solution or numerical scheme at the generation-dissipation step of the turbulence model leads to better representation of ocean climate than the faster parameterization using the asymptotic behavior of the analytical solution. At the same time, the computational efficiency left almost unchanged relative to the simple PP parameterization. Usage of PP parametrization in the circulation model leads to realistic simulation of density and circulation with violation of T,S-relationships. This error is majorly avoided with using the proposed parameterizations containing the split turbulence model

  9. High-resolution records of thermocline in the Okinawa Trough since about 10000 aBP

    Institute of Scientific and Technical Information of China (English)

    WANG; Jiliang; (


    [1]Ye, D. Z., Zeng, Q. C., Guo, Y. F. (eds.), Modern Climate (in Chinese), Beijing: Climate Press, 1991.[2]Chen, M. T., Prell, W. L., Faunal distribution patterns of planktonic foraminifera in surface sediments of the low-latitude Pacific, Paleo., Paleo., Paleo., 1995, 137: 55.[3]Ravelo, A. C., Fairbanks, R. G., Philander, G., Reconstructing tropical Atlantic hydrography using planktonic foraminifera and ocean model, Paleoceanography, 1990, 5(3): 409.[4]Ravelo, A. C., Fairbanks, R. G., Oxygen isotopic composition of multiple species of planktonic foraminifera: recorders of the modern photic zone temperature gradient, Paleoceanography, 1992, 7(6): 815.[5]Andreason, D. J., Ravelo, A. C., Tropical Pacific Ocean thermocline depth reconstructions for the last glacial maximum, Paleoceanography, 1997, 12(3): 395.[6]Schmit, H., Berger, W. H., Bickert, H. et al., Quaternary carbon isotope records of pelagic foraminifers: Site 806, Ontong Java Plateau, Proc. ODP, Sci. Result, 1993, 130: 397.[7]Chen, X. R., Wang, P. X., Approach to vertical structure variation of upper layer in the Okinawa Trough using nannofossils, Science in China, Series D, 1998, 41(3): 290.[8]Li, B., Zhao, Q., Wang, Y. et al., Paleoceanographic events of the southern Okinawa Trough during last 20000 years, Acta Oceanologica Sinica, 1998, 17(4): 519.[9]Wang, J. L., The changes of thermocline depth in the northern Okinawa Trough during the Holocene, Quaternary Sciences (in Chinese), 1999, 3: 281.[10]Jin, X. L. (ed.), Geology of the East China Sea (in Chinese with English abstract), Beijing: Ocean Press, 1992.[11]First & Second Institutes of Oceanography, SOA Essays on the investigation of Kuroshio Current (in Chinese with English abstract), Beijing: Ocean Press, 1987, 1?/FONT>345.[12]Department of Science and Technology, SOA, Essays on the investigation of Kuroshio Current, Series IV (in Chinese with English abstract), Beijing: Ocean Press, 1992, 1?/FONT>332.

  10. The seasonal upwellings in the Gulf of Guinea (United States)

    Verstraete, Jean-Marc

    equatorial thermostad thickness. In aay 1984, a deep eastward jet was observed at 4°W carrying about 3 ×10 6m 3s -1 deformation and below the base of the thermostad, clearly separated from the EUC. Then, maximum thermostad development was found in July 1984, related to the shoalin of the deep jet and of the EUC. The top of the deep jet had shoaledto about 200m and its transport increased to about 4.6 × 10 6m 3s -1 within 1°30'N - 1°30'S. The spreading of the isotherms from about 300m is indicative of a geostrophic balance. Simultaneously, the equatorial thermocline was uplifted near the surface, although the base of the thermostad (13°C isotherm) remained nearly stationary. Analysis of the perturbation temperature field shows that variations of the 19°C isotherm depth as well as the thickness of the equatorial thermostad were strongly equatorially trapped, with scales associated with the second baroclinic mode. In the absence of local forcing in the Gulf of Guinea from January to July 1984, the only causal effect to explain these large perturbations in the upper 400m lies in the changes in the zonal wind stress to the west of the Gulf. The distinct semi-annual cycle observed in the thermal and salinity structures in the Gulf could be attributable to the semiannual signal in the zonal wind stress to the east of 30°W. Numerical experiments by PHILANDER and PACANOWSKI (1986a) confirm that remote forcing by changes in zonal wind stress in the western-central equatorial Atlantic is the main process in seasonal changes in the thermocline depth in the eastern equatorial Atlantic, and a secondary process along the coasts. The thinning of the thermostad in July 1984 at 3° - 4°N associated with a strong Guinea current, concommitant with its thickening at the equator associated with a deep eastward jet, suggests that the upwelling along the coast is essentially a consequence of the equatorial adjustment in response to the zonal wind stress in the equatorial zone 10°W - 35

  11. Estudio eco-epidemiológico de la tripanosomiasis americana en el municipio de Amalfi (Antioquia

    Directory of Open Access Journals (Sweden)

    J. Arboleda


    . geniculatus y P. rufotuberculatus, los cuales fueron corroborados por morfología en ninfas y adultos y por microscopía electrónica de barrido en huevos, teniendo como base de comparación huevos de colonias preestablecidas de ambas especies.

    Se capturaron 33 animales silvestres pertenecientes a géneros como: Didelphis, Marteja, Marmosa, Hoplomys, Dasypus, Proechymis, Poechinus, Oryzomis, Philander y Rodentia. Un 20.0% de ellos resultaron positivos para T. cruzi, mediante ELISA. En cuanto a los reservorios domésticos, el 47.6 % de las muestras de caninos fueron positivas por ELISA, el 10 % por ELISA e IFI.

    Al determinar la seroprevalencia humana se encontró en la vereda La Gardenia una mujer de 22 años, que presentó positividad por T. cruzi para las pruebas de ELISA e IFI con títulos de 1:160, éste sería el primer caso de seropositividad confirmada para T. cruzi en Antioquia.

    Debido a la presencia T. cruzi en vectores, reservorios y en un humano y a las evidencias de reproducción intradomiciliaria, éste es el primer caso para Colombia donde se demuestra el alto riesgo y la importante tendencia a la domiciliación, de dos especies del género Panstrongylus, no consideradas vectoras de la enfermedad de Chagas.