972 resultados para Rhinoceros (Genus)


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The following two new species of Culicoides from the Argentinean Yungas are described, illustrated and placed to subgenus or species group and compared with related congeners: Culicoides calchaqui Spinelli & Veggiani Aybar and Culicoides willinki Spinelli & Veggiani Aybar. Culicoides daedaloides Wirth & Blanton is recorded for the first time for Argentina and Culicoides pseudoheliconiae Felippe-Bauer is firstly mentioned from the northwestern region of the country.

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The family Acrochordiceratidae Arthaber, 1911 ranges in age from latest Spathian to the middle/late Anisian boundary, and it represents a major component of ammonoid faunas during that time. The middle Anisian genus Acrochordiceras Hyatt, 1877 is the most widespread taxon of the family and occurs abundantly worldwide within the low paleolatitude belt. However, there is a profusion of species names available for Acrochordiceras. This excessive diversity at the species level essentially results from the fact that sufficiently large samples were not available, thus leading to a typological approach to its taxonomy. Based on new extensive collections obtained from the Anisian (Middle Triassic) Fossil Hill Member (Star Peak Group, north-west Nevada) for which a high resolution biostratigraphic frame is available, the taxonomy and biostratigraphy of the genus Acrochordiceras Hyatt, 1877 is herein revised with respect to its intra-specific variation. Morphological and biometric studies (c. 550 bedrock-controlled specimens were measured) show that only one species occurs in each stratigraphic level. Continuous ranges of intra-specific variation of studied specimens enable us to synonymize Haydenites Diener, 1907, Silesiacrochordiceras Diener, 1916 and Epacrochordiceras Spath, 1934 with Acrochordiceras Hyatt, 1877. Three stratigraphically successive species are herein recognized in the low paleolatitude middle Anisian faunas from Nevada: A. hatschekii (Diener, 1907), A. hyatti Meek, 1877 and A. carolinae Mojsisovics, 1882. Moreover, an assessment of intra-specific variation of the adult size range does not support recognition of a dimorphic pair (Acrochordiceras and Epacrochordiceras) as previously suggested by other workers (Epacrochordiceras is the compressed and weakly ornamented end-member variant of Acrochordiceras). The successive middle Anisian species of Acrochordiceras form an anagenetic lineage characterized by increasing involution, adult size and intra-specific variation. This taxonomic revision based on new bedrock-controlled collections is thus an important prerequisite before studying the evolution of the group.

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Germination experiments were performed with seeds of two species of genus Allium section Allium, a rare and endangered species A. pyrenaicum and a common A. sphaerocephalon. Different pre-treatments and a photoperiod of 24 h darkness were applied in order to simulate different germination conditions. Both species showed a high percentage of viable seeds a part of which were dormant. An elevate percentage of dormant seeds could be caused by a later collection time. Low altitude populations had more mortality than the others, possibly caused by the hard summer conditions during flowering and fruiting time. Comparisons between dates of species coexistence localities only show inter-population variability and it could be caused by the detected dormancy. Darkness accelerates germination, possibly for elongation radicle stimulation. Heat-shock pre-treatments decreased germination time in seeds from localities where fire is a probable event. The rarity of A. Pyrenaicum not seems to be caused by restricted germination requirements but is attributable to distinct habitat preferences, related to his altitudinal range of distribution

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Thirty strains from the 11 species of the genus Leptospira were studied by multilocus enzyme electrophoresis at 12 enzyme loci, all of which were polymorphic. The mean number of alleles per locus was 6.5. Twenty-five electrophoretic types were distinguished. Grouping of the strains by cluster analysis was in general agreement with species delineation as determined by DNA-DNA hybridization, except for the strains of Leptospira meyeri and Leptospira inadai, which were scattered throughout the genus, reflecting previously recognized taxonomic uncertainties. Analysis of the clonality within Leptospira interrogans sensu stricto indicated that this population was relatively heterogeneous and a lack of gene linkage disequilibrium could not be excluded. There was a genetic discrimination between the pathogenic species and the saprophytic ones. The phenotypically intermediate species (L. inadai and Leptospira fainei) were also genetically separated and were probably closer to the saprophytes than to the pathogens.

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RÉSUMÉ Une espèce est rarement composée d'une population unique. Parce que les individus ont des capacités de dispersion limitées et que les paysages sont des mosaïques d'habitats, la plupart des espèces sont plutôt composées de sous-populations connectées par la migration. Cette variation spatiale influence directement la distribution de la variabilité génétique dans et entre les populations. Durant ce travail, nous avons abordé certains des processus populationnels qui ont joué un rôle supposé dans l'apparition de nouvelles espèces au sein du genre Trochulus. Plus précisément, nous avons tenté d'évaluer les impacts respectifs de l'isolement passé (facteurs historiques) et présent (facteurs locaux). Nous avons d'abord pu montrer que les faibles capacités de dispersion des escargots terrestres ont directement influencé leur histoire évolutive à toutes les échelles spatiales et temporelles. En réduisant l'effet homogénéisant de la migration, une faible dispersion maintient dans les populations les traces génétiques d'évènements passés. A l'échelle de la distribution globale de Trochulus villosus, ces traces ont permis de reconstruire une histoire faite d'isolements et d'expansions de populations. En combinant des données génétiques avec une modélisation de la niche climatique passée, il a été possible de proposer un scénario significativement meilleur que toutes les hypothèses alternatives que nous avons testées. A l'échelle locale par contre, l'héritage historique est difficile à distinguer de la dynamique actuelle. Ce fut le cas des lignées mitochondriales du complexe sericeus-hispidus : les deux principales lignées étaient phylogénétiquement éloignées, avaient eu des démographies passées différentes et corrélaient avec des différences morphologiques. D'un autre côté, le flux de gène nucléaire était fort, contredisant l'idée de deux espèces cryptiques isolées reproductivement. Pour pouvoir conclure à la présence ou non de deux espèces, il nous a manqué des informations locales sur la dynamique des populations et les conditions écologiques que l'on trouve dans la région d'étude. Enfin, nous avons pu souligner que la connectivité entre populations d'escargots est soumise à la qualité des habitats et à leur organisation spatiale. Les escargots sont dépendants d'un habitat et s'y adaptent, comme l'indiquent la présence de «poils » uniquement sur la coquille d'espèces vivant dans des habitats humides ou la corrélation entre morphologie et habitat au sein du complexe sericeus-hispidus. Logiquement donc, les escargots migrent préférentiellement au travers d'habitats favorables comme l'a montré la réduction de flux de gènes au travers des prairies chez T. villosus (une espèce forestière). De ces données, nous pouvons supposer que les populations d'escargots en particulier, et des espèces à faible dispersion en général, ont de fortes chances d'être affectées par les changements climatiques, avec de probables implications pour leurs histoires évolutives. SUMMARY : Species rarely consists in a single population. Because individuals have limited dispersal abilities, because landscapes are habitat patchworks, most species are made of several subpopulations connected by migration. This spatial variation has consequences on the distribution of genetic diversity within and between populations, creating a structure among the populations. During the present work, we investigated some of the population processes assumed to have played an important role on the speciation within the genus Trochulus. More specifically, we questioned the respective impacts of past (historical factors) or present (local factors) population isolations. We first could show that the poor dispersal abilities of land snails have had profound impacts on their evolutionary histories at all spatial and temporal scales. Low dispersal maintains a strong signature of past events in the populations by minimising the homogenising effects of geneflow. At the scale of Trochulus villosus global distribution, they allowed to retrieve the detailed history of this species population isolations and expansions. Combining a large genetic dataset with paleo-climatic niche modelling ended up with a historical scenario significantly better than all traditional alternatives we tested. At local scale on the contrary, past events become difficult to tease apart from ongoing processes. This was the case for the divergent mitochondria) lineages within the sericeus-hispidus complex: the two principal lineages appeared to be phylogenetically distant, to have experienced different demographic histories and to correlate with morphological differences. On the other hand, nuclear (present day) geneflow was high, contradicting the idea of two reproductively isolated cryptic species. Information on the local population dynamics and environmental conditions are lacking to be able to decide whether past isolation has indeed resulted here in new species. Finally, we emphasised the importance of the habitat types present in a landscape as well as their spatial organisation for the population connectivity of land snails. These species are tightly dependent on a habitat and adapt to it as shown by thé occurrence of hair-like structures only in species living in humid environments or by the correlation between shell morphology and habitat in the sericeus-hispidus complex. As a result, land snails preferentially migrate through favourable habitats: Trochulus villosus, a forest species, had its geneflow significantly reduced across meadows. From these data, we can hypothesise that the populations of land snails in particular and of low dispersing species in general are likely to be strongly affected by the ongoing climate changes, with potential major consequences on their evolutionary histories.

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A redescription of the genus Bruchopria and its two species, B. hexatoma Kieffer (female and male) and B. pentatoma Kieffer (male only) is presented. New record for B. hexatoma from Argentina is provided. Some aspects of diapriid biology with emphasis on their myrmecophilic evidence and association with ants are discussed. Scanning photographs of morphological structures are included.

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The genus Chalcolepidius is revised. Type specimens of 65 nominal species, except C. costatus Pjatakowa, 1941, C. fleutiauxi Pjatakowa, 1941 and C. viriditarsus Schwarz, 1906, are examined. Eighty five species are studied, of which 34 are synonymyzed and 12 new species described; three species, C. alicii Pjatakowa, 1941, C. haroldi Candèze, 1878 and C. unicus Fleutiaux, 1910, formely included in this genus, are not congeneric and are removed; C. validus Candèze, 1857 is revalidated. The genus is now formed by 63 species. Redescriptions, illustrations and a key for the examined species, and a cladistic analysis for groups of species are also included. New synonyms established: C. apacheanus Casey, 1891 = C. simulans Casey, 1907 syn. nov. = C. acuminatus Casey, 1907 syn. nov. = C. nobilis Casey, 1907 syn. nov.; C. approximatus Erichson, 1841 = C. aztecus Casey, 1907 syn. nov. = C. niger Pjatakowa, 1941 syn. nov.; C. attenuatus Erichson, 1841 = C. cuneatus Champion, 1894 syn. nov. = C. tenuis Champion, 1894 syn. nov.; C. aurulentus Candèze, 1874 = C. candezei Dohrn, 1881 syn. nov. = C. grossheimi Pjatakowa, 1941 syn. nov.; C. bomplandii Guérin, 1844 = C. humboldti Candèze, 1881 syn. nov.; C. chalcantheus Candèze, 1857 = C. violaceous Pjatakowa, 1941 syn. nov.; C. cyaneus Candèze, 1881 = C. scitus Candèze, 1889 syn. nov. = C. abbreviatovittatus Pjatakowa, 1941 syn. nov.; C. desmarestii Chevrolat, 1835 = C. brevicollis Casey, 1907 syn. nov.; C. gossipiatus Guérin, 1844 = C. erichsonii Guérin-Méneville, 1844 syn. nov. = C. lemoinii Candèze, 1857 syn. nov.; C. inops Candèze, 1886 = C. murinus Champion, 1894 syn. nov.; C. jansoni Candèze, 1874 = C. mucronatus Candèze, 1889 syn. nov.; C. lacordairii Candèze, 1857 = C. exquisitus Candèze, 1886 syn. nov. = C. monachus Candèze, 1893 syn. nov.; C. lenzi Candèze, 1886 = C. behrensi Candèze, 1886 syn. nov.; C. oxydatus Candèze, 1857 = C. jekeli Candèze, 1874 syn. nov.; C. porcatus (Linnaeus, 1767) = C. peruanus Candèze, 1886 syn. nov. = C. flavostriatus Pjatakowa, 1941 syn. nov. = C. herbstii multistriatus Golbach, 1977 syn. nov.; C. rugatus Candèze, 1857 = C. amictus Casey, 1907 syn. nov.; C. smaragdinus LeConte, 1854 = C. ostentus Casey, 1907 syn. nov. = C. rectus Casey, 1907 syn. nov.; C. sulcatus (Fabricius, 1777) = C. herbstii Erichson, 1841 syn. nov; C. virens (Fabricius, 1787) = C. perrisi Candèze, 1857 syn. nov.; C. virginalis Candèze, 1857 = C. championi Casey, 1907 syn. nov.; C. viridipilis (Say, 1825) = C. debilis Casey, 1907 syn. nov.; C. webbi LeConte, 1854 = C. sonoricus Casey, 1907 syn. nov.; C. zonatus Eschscholtz, 1829 = C. longicollis Candèze, 1857 syn. nov. New species described: C. albisetosus sp. nov. (Ecuador), C. albiventris sp. nov. (Mexico: Veracruz), C. copulatuvittatus sp. nov. (Venezuela), C. extenuatuvittatus sp. nov. (Venezuela), C. fasciatus sp. nov. (Mexico: Durango), C. ferratuvittatus sp. nov. (Ecuador), C. proximus sp. nov. (Mexico: Sinaloa), C. serricornis sp. nov. (Mexico: Veracruz), C. spinipennis sp. nov. (Mexico: Veracruz), C. supremus sp. nov. (Venezuela), C. truncuvittatus sp. nov. (Mexico: Tamaulipas) and C. virgatipennis sp. nov. (Mexico: Durango). Redescribed species: C. angustatus Candèze, 1857, C. apacheanus Casey, 1891, C. approximatus Erichson, 1841, C. attenuatus Erichson, 1841, C. aurulentus Candèze, 1874, C. bomplandii Guérin-Méneville, 1844, C. boucardi Candèze, 1874, C. chalcantheus Candèze, 1857, C. corpulentus Candèze, 1874, C. cyaneus Candèze, 1881, C. desmarestii Chevrolat, 1835, C. dugesi Candèze, 1886, C. erythroloma Candèze, 1857, C. eschscholtzi Chevrolat, 1833, C. exulatus Candèze, 1874, C. fabricii Erichson, 1841, C. forreri Candèze, 1886, C. fryi Candèze, 1874, C. gossipiatus Guérin-Méneville, 1844, C. inops Candèze, 1886, C. jansoni Candèze, 1874, C. lacordairii Candèze, 1857, C. lafargi Chevrolat, 1835, C. lenzi Candèze, 1886, C. limbatus (Fabricius, 1777), C. mexicanus Castelnau, 1836, C. mniszechi Candèze, 1881, C. mocquerysii Candèze, 1857, C. morio Candèze, 1857, C. obscurus Castelnau, 1836, C. oxydatus Candèze, 1857, C. porcatus (Linnaeus, 1767), C. pruinosus Erichson, 1841, C. rodriguezi Candèze, 1886, C. rostainei Candèze, 1889, C. rubripennis LeConte, 1861, C. rugatus Candèze, 1857, C. silbermanni Chevrolat, 1835, C. smaragdinus LeConte, 1854, C. sulcatus (Fabricius, 1777), C. tartarus Fall, 1898, C. validus Candèze, 1857, reval., C. villei Candèze, 1878, C. virens (Fabricius, 1787), C. virginalis Candèze, 1857, C. viridipilis (Say, 1825), C. webbi LeConte, 1854, C. zonatus Eschscholtz, 1829.

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A new genus and new species of Phlebotominae, Edentomyia piauiensis (Diptera, Psychodidae) from a cave in Piauí State, Brazil, are described. This new genus belongs to Phlebotomini, but its inclusion in any subdivision of this tribe depends on further study.

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The genus Agelaia Lepeletier 1836 belongs to the swarming genera of the Polistinae, with species distributed from Mexico to northern Argentina. Fifteen of the 31 described species are found in Brazil. Four species occur in the State of Rio Grande do Sul, two of them recorded herein for the first time. Redescriptions and a key to these species are provided.

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Diopsosoma Malloch, 1932 and its only included species, D. primum Malloch, 1932 are redescribed. While the genus is remarkable and easily recognized by its laterally elongate head that is produced into eyestalks, it is otherwise virtually unknown. To bring attention to this extraordinary fly we redescribe it within the context of brief descriptions of the family Periscelididae and subfamily Periscelidinae. We also provide an annotated key to the described genera of Periscelididae and a photographic montage of the holotype, which is perhaps the only preserved specimen of this genus and species.

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The following new taxa of South American Cercopidae are described: Ferorhinella gen. nov., with type species Sphenorhina brevis Walker, 1851; Deois (Deois) knighti sp. nov. (Brazil), Deois (Deois) sexpunctata sp. nov. (Brazil), Deois (Pandysia) constricta sp. nov. (Brazil), Mahanarva (Ipiranga) bahiaensis sp. nov. (Brazil), Maxantonia bifurcata sp. nov. (Brazil), Neosphenorhina curvipenis sp. nov. (Brazil), Sphenorhina brevispina sp. nov. (Ecuador), Sphenorhina nigricephala sp. nov. (Ecuador), Sphenorhina minuta sp. nov. (Brazil), Tropidorhinella onorei sp. nov. (Colombia), Zuata luteofascia sp. nov. (Colombia). Ferorhinella brevis (Walker, 1851) comb. nov. In addition, descriptions are given for a new colour form of Mahanarva (M.) phantastica (Breddin, 1904) and a newly found variation in the male genitalia of Deoisella fasciata Costa & Sakakibara, 2002.