977 resultados para Nautiloid (new genus)


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Mode of access: Internet.

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Sammanfattning/Abstract I denna studie har vi med det amerikanska samhällets erfarenhet av det inhemska fängelsesystemet som grund valt att studera de två tv-serierna Oz och Orange is the New Black. Utifrån detta har vi undersökt hur fängelserna i dessa serier porträtteras, hur två framträdande fångar porträtteras, hur interaktionen mellan fångar och fängelsemiljön ser ut i berättelsernas struktur samt studerat gestaltningen av fångarna ur ett genus och etnicitetsperspektiv. Vi använder oss av ett flertal teorier som berör det amerikanska samhället, dess fängelsesystem samt genus och etnicitet. Vi har använt oss av narratologisk och semiotisk metodik för att studera seriernas innehåll rörande porträttering av karaktärer och berättarstruktur. I vår slutdiskussion kommer vi fram till att det finns en gemensam kritik av fängelser som brottsförebyggande instans och att porträtteringen av seriernas karaktärer både bryter och cementerar vissa normer rörande genus och etnicitet. Vi finner även ett typiskt narrativt för den genre vi valt att undersöka som är fängelsegenren.                

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A new thelastomatid, Aoruroides queenslandensis, is described from two native Australian cockroaches, Panesthia tryoni tryoni Shaw and P. cribrata Saussure, from sub-tropical rainforest in south-eastern Queensland. Species of Aoruroides Travassos & Kloss, 1958 have previously been reported from cockroaches found in Brazil and the Philippines, but A. queenslandensis n. sp. is the first species of this genus found in Australia. The new species differs from the other members of Aoruroides principally in the position of the nerve-ring and egg morphology.

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In recent years there has been much progress in our understanding of the phylogeny and evolution of ticks, in particular the hard ticks (Ixodidae). Indeed, a consensus about the phylogeny of the hard ticks has emerged which is quite different to the working hypothesis of 10 years ago. So that the classification reflects our knowledge of ticks, several changes to the nomenclature of ticks are imminent or have been made. One subfamily, the Hyalomminae, should be sunk, while another, the Bothriocrotoninae, has been created (Klompen, Dobson & Barker, 2002). Bothriocrotoninae, and its sole genus Bothriocroton, have been created to house an early-diverging ('basal') lineage of endemic Australian ticks that used to be in the genus Aponomma. The remaining species of the genus Aponomma have been moved to the genus Amblyomma. Thus, the name Aponomma is no longer a valid genus name. The genus Rhipicephalus is paraphyletic with respect to the genus Boophilus. Thus, the genus Boophilus has become a subgenus of the genus Rhipicephalus (Murrell & Barker, 2003). Knowledge of the phylogenetic relationships of ticks has also provided new insights into the evolution of ornateness and of their life cycles, and has allowed the historical zoogeography of ticks to be studied. Finally, we present a list of the 899 valid genus and species names of ticks as of February 2004.

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A new acantha species-group is erected in the genus Euhesma Michener. Three new species are described: E. acantha, E. loorea, and E. collaris. Scanning electron micrographs and line drawings illustrate the species-group and a key to females enables the separation of species. Known distributions are mapped.

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We describe one new species of Telotrema Ozaki, 1933 from the intestine of an acanthurid fish of the Great Barrier Reef. Telotrema brevicaudatum n. sp. is described from 2 mature specimens from the yellowfin surgeonfish, Acanthurus xanthopterus Valenciennes, 1835 ( Acanthuridae), from waters off Lizard Island, Queensland, Australia. This species is distinguished from the type-species, Telotrema caudatum Ozaki, 1933, by the smaller excretory papilla, the massive pars prostatica, the unipartite, globular seminal vesicle, and the intertesticular position of the ovary. The proposal of a new species of Telotrema necessitates re-examination of the generic diagnosis, and the genus is here redefined in light of the morphology of T. brevicaudatum. Telotrema is distinguished from Gyliauchen Nicoll, 1915 by the possession of a ventral sucker which is larger than the pharynx, a straight or sigmoid oesophagus, an extensive and dense vitellarium, and a distinct excretory papilla. We here recognise 3 species and distinguish them in a key. The biogeographical range for species of Telotrema now includes acanthurid and pomacentrid fishes of the western Pacific Ocean.

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A nematocidal agent present in a southern Australian marine sponge of the genus Echinodictyum has been isolated and identified by detailed spectroscopic analysis and total synthesis as the novel betaine (-)-echinobetaine A (6). Preliminary SAR investigations have been undertaken.

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The principle nematocidal agent present in a southern Australian marine sponge of the genus Echinodictyum has been isolated and identfied as the novel betaine (+)-echinobetaine B (6), and the structure assigned by spectroscopic analysis has been confirmed by total synthesis. Preliminary SAR conclusions are drawn from analysis of synthetic intermediates and the known marine metabolites zooanemonin (12) and norzooanemonin (13), and the new sponge metabolite norzooanemonin methyl ester (14). The latter compound is reported for the first time from a selection of Australian sponges, including an Axinyssa sp., a Niphates sp., an Axinella sp. and a Ptilocaulis sp.

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Phylogenetic analysis of the ketosynthase (KS) gene sequences of marine sponge-derived Salinispora strains of actinobacteria indicated that the polyketide synthase (PKS) gene sequence most closely related to that of Salinispora was the rifamycin B synthase of Amycolatopsis mediterranei. This result was not expected from taxonomic species tree phylogenetics using 16S rRNA sequences. From the PKS sequence data generated from our sponge-derived Salinispora strains, we predicted that such strains might synthesize rifamycin-like compounds. Liquid chromatography-tandem mass spectrometry (LC/MS/MS) analysis was applied to one sponge-derived Salinispora strain to test the hypothesis of rifamycin synthesis. The analysis reported here demonstrates that this Salinispora isolate does produce compounds of the rifamycin class, including rifamycin B and rifamycin SV. A rifamycin-specific KS primer set was designed, and that primer set increased the number of rifamycin-positive strains detected by PCR screening relative to the number detectable using a conserved KS-specific set. Thus, the Salinispora group of actinobacteria represents a potential new source of rifamycins outside the genus Amycolatopsis and the first recorded source of rifamycins from marine bacteria.

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Four new species and two new genera of thelastomatoid are described from several species of Australian burrowing cockroaches (Blattodea: Panesthiinae; Geoscapheinae). Corpicracens munozae n. g., n. sp., Pseudodesmicola botti n. g., n. sp. and Cephalobellus nolani n. sp. are described from Geoscapheus dilatatus (Blattodea: Geoscapheinae) from Mendooran, New South Wales; one new thelastomatid, Blattophila praelongicauda n. sp., is described from Panesthia cribrata from Lamington National Park, Queensland. Corpicracens munozae n. g., n. sp. is long and slender, with a monodelphic female reproductive system, a clavate corpus with a slight posterior pseudobulb, oval eggs flattened at the poles, and a relatively robust, subulate tail. Pseudodesmicola botti n. g., n. sp. is slightly more robust in body, also has a monodelphic reproductive system, a cylindrical corpus with a posterior pseudobulb, ovoid eggs and a very long, subulate tail. Cephalobellus nolani n. sp. is distinguished from other members of the genus by its relatively short and broad body and egg shape. Lastly, Blattophila praelongicauda n. sp. is distinguished from other members of the genus by having eggs with a single, polar operculum, tail length, and position of the vulva, nerve ring and excretory pore. An additional species, known by a single specimen from Panesthia tryoni tryoni from the same locality is characterised but not named. The species found are all relatively rare parasites of Australian burrowing cockroaches, each having a prevalence of less than 10%.

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Envekadea metzeltinii sp. nov. is described from periphyton assemblages in the subtropical karstic wetlands of the Florida Everglades, U.S.A. The morphology of the new diatom species is documented by light and scanning electron micrographs and discussed in detail, including comparisons with related species in the genera Envekadea, Caloneis, andNavicula. The new species is characterized by a linear valve outline, a sigmoid raphe course, broad variability in areola shapes and sizes, and two clearly raised axial costae. Apart from the type locality in Florida, the species was observed from similar wetlands in the Yucatan, Mexico. Notes on its ecology and distribution are added. Based on the morphology of the most similar species, Navicula palestinae, the latter is transferred to the genus Envekadea.

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As a result of a floristic survey carried out in riparian habitats of northern Spain, new chorological data are provided for 9 alien and 6 native plant species. Some species are reported for the first time at regional scale, such as Carex strigosa, Helianthus x laetiflorus and Persicaria pensylvanica in Cantabria. Also noteworthy is the finding of naturalised populations of the North American grass Muhlenbergia schreberi at the Urumea river basin, which represents the second reference for the Iberian Peninsula.

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The coccolithophore genus Gephyrocapsa contains a cosmopolitan assemblage of pelagic species, including the bloom-forming Gephyrocapsa oceanica, and is closely related to the emblematic coccolithophore Emiliania huxleyi within the Noëlaerhabdaceae. These two species have been extensively studied and are well represented in culture collections, whereas cultures of other species of this family are lacking. We report on three new strains of Gephyrocapsa isolated into culture from samples from the Chilean coastal upwelling zone using a novel flow cytometric single-cell sorting technique. The strains were characterized by morphological analysis using scanning electron microscopy and phylogenetic analysis of 6 genes (nuclear 18S and 28S rDNA, plastidial 16S and tufA, and mitochondrial cox1 and cox3 genes). Morphometric features of the coccoliths indicate that these isolates are distinct from G. oceanica and best correspond to G. muellerae. Surprisingly, both plastidial and mitochondrial gene phylogenies placed these strains within the E. huxleyi clade and well separated from G. oceanica isolates, making Emiliania appear polyphyletic. The only nuclear sequence difference, 1 bp in the 28S rDNA region, also grouped E. huxleyi with the new Gephyrocapsa isolates and apart from G. oceanica. Specifically, the G. muellerae morphotype strains clustered with the mitochondrial β clade of E. huxleyi, which, like G. muellerae, has been associated with cold (temperate and sub-polar) waters. Among putative evolutionary scenarios that could explain these results we discuss the possibility that E. huxleyi is not a valid taxonomic unit, or, alternatively the possibility of past hybridization and introgression between each E. huxleyi clade and older Gephyrocapsa clades. In either case, the results support the transfer of Emiliania to Gephyrocapsa. These results have important implications for relating morphological species concepts to ecological and evolutionary units of diversity.

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The coccolithophore genus Gephyrocapsa contains a cosmopolitan assemblage of pelagic species, including the bloom-forming Gephyrocapsa oceanica, and is closely related to the emblematic coccolithophore Emiliania huxleyi within the Noëlaerhabdaceae. These two species have been extensively studied and are well represented in culture collections, whereas cultures of other species of this family are lacking. We report on three new strains of Gephyrocapsa isolated into culture from samples from the Chilean coastal upwelling zone using a novel flow cytometric single-cell sorting technique. The strains were characterized by morphological analysis using scanning electron microscopy and phylogenetic analysis of 6 genes (nuclear 18S and 28S rDNA, plastidial 16S and tufA, and mitochondrial cox1 and cox3 genes). Morphometric features of the coccoliths indicate that these isolates are distinct from G. oceanica and best correspond to G. muellerae. Surprisingly, both plastidial and mitochondrial gene phylogenies placed these strains within the E. huxleyi clade and well separated from G. oceanica isolates, making Emiliania appear polyphyletic. The only nuclear sequence difference, 1 bp in the 28S rDNA region, also grouped E. huxleyi with the new Gephyrocapsa isolates and apart from G. oceanica. Specifically, the G. muellerae morphotype strains clustered with the mitochondrial β clade of E. huxleyi, which, like G. muellerae, has been associated with cold (temperate and sub-polar) waters. Among putative evolutionary scenarios that could explain these results we discuss the possibility that E. huxleyi is not a valid taxonomic unit, or, alternatively the possibility of past hybridization and introgression between each E. huxleyi clade and older Gephyrocapsa clades. In either case, the results support the transfer of Emiliania to Gephyrocapsa. These results have important implications for relating morphological species concepts to ecological and evolutionary units of diversity.