• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 4
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • Tagged with
  • 7
  • 3
  • 3
  • 3
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 1
  • 1
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

The effects of harvesting and decaying logs on oribatid (Acari:Oribatida) mite assemblages in eastern Canadian mixedwood boreal forest

Déchêne, Andrea D. January 1900 (has links)
Thesis (M.Sc.). / Written for the Dept. of Natural Resource Sciences. Title from title page of PDF (viewed 2008/05/14). Includes bibliographical references.
2

Feeding biology and diversity of oribatid mites (Oribatida, Acari)

Schneider, Katja, January 2005 (has links)
Thesis (doctoral)--Technische Universität Darmstadt, 2005. / Title from PDF title page (viewed on Apr. 25, 2007). Includes bibliographical references (p. 95-115).
3

Acaros associados a algumas aves domesticas, sinantropicas e silvestres da Região de Campinas, SP (Acari: Astigmata: Prostigmata e Mesostigmata) / Feather mites, nests mites and quill mites associated to some domestic, synantrhopic and wild birds of the Campinas region, SP, Brazil (Arachnida : Acari; Aves)

Vilas Boas Filho, David 30 May 2008 (has links)
Orientador: Angelo Pires do Prado / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-11T07:10:40Z (GMT). No. of bitstreams: 1 VilasBoasFilho_David_M.pdf: 2394363 bytes, checksum: f690bd586210a5c24d08312faa15e2b5 (MD5) Previous issue date: 2008 / Resumo: Os objetivos desse estudo foram identificar os ácaros associados a algumas aves domésticas, sinantrópicas e silvestres da região de Campinas, SP e iniciar uma coleção desses artrópodos, como base para futuros estudos na área. Para isso, foram coletados ácaros das penas da asa, cauda e do corpo das aves, que após exame ao microscópio estereoscópico, eram retirados manualmente, fixados em líquido de Vitzthum ou lactofenol e montados em meio de Hoyer, para exame ao microscópio óptico; o exame era feito na superfície ventral de asa e o cálamo era aberto, longitudinalmente e seu interior examinado. Ninhos naturais também foram examinados e os ácaros associados coletados manualmente. A amostragem se deu de modo aleatório e eventual, pois só utilizamos animais mortos acidentalmente, que eram enviados para o Laboratório de Entomologia do Departamento de Parasitologia, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP). As amostras foram obtidas de criações em cativeiro (galinha doméstica, calopsita e periquito-australiano) e de aves sinantrópicas (pombo doméstico, avoante, rolinha e outros) e silvestres (troquilídeo e outros). O material testemunho foi depositado na coleção de ácaros do Departamento de Parasitologia, IB, UNICAMP. Algumas das conclusões são as seguintes: Os estágios de vida livre [deutoninfa (hipopo), tritoninfa, fêmea grávida, e macho heteromórfico] de Hipodectes propus são descritos como ocorrendo, pela primeira vez no Brasil, encontrados em ninho de Zenaida auriculata (Des MURS), que também é novo hospedeiro. É relatada a ocorrência de três espécies do gênero Pellonyssus (YUNKER & RADOVSKY), que são nidícolas, hematófagas: P.gorgasi, P. marui e P. reedi. Também pela primeira vez, foi encontrado nas penas da asa e da cauda da calopsita Nymphicus hollandicus (KERR), o ácaro pteroliquídeo Nymphicilichus perezae MIRONOV & GALLOWAY, 2002. Nos periquitos australianos Melopsittacus undulatus (SHAW) assinalamos a presença, também pela primeira vez no Brasil, dos ácaros plumícolas, Sideroferus lunula (ROBIN) e Dubininia melopsittaci (GAUD & ATYEO, 1987). Foi observada a associação hiperparasitaforética entre fêmeas grávidas e ovos larvados de Myialges anchora TROUESSART, 1906 e a mosca do pombo, Pseudolynchia canariensis (MACQUART,1840). Descreve-se a associação entre ácaros calamícolas e a galinha doméstica caipira, Gallus gallus domesticus L.: são descritos, Syringophilus bipectinatus HELLER, 1880, e Dermoglyphus elongatus (ROBIN & MÉGNIN, 1877), espécies relativamente comuns, além de duas outras espécies assinaladas pela primeira vez para o Brasil: Paralges pachycnemis TROUESSART & MÉGNIN, 1884 e Gaudoglyphus minor (NÖRNER, 1882). Esse grupo de ácaros é muito pouco conhecido das aves que ocorrem no Brasil, necessitando de um esforço muito grande para aumentar o conhecimento da diversidade de espécies e de suas interações biológicas, extremamente interessantes / Abstract: The main goals of this study were to identify mites associated to some domestic, synanthropic and wild birds from Campinas, SP, and surrounding areas, as well as to establish a collection of those arthropods as a supporting material for future studies in this area. To do so, mites were first collected from wings, tail and body feathers of birds. After microscopic examination the specimens were manually assembled, fixed with Vitzthum¿s fluid or lactophenol and then mounted in Hoyer¿s medium for analysis under optical microscope. The ventral surface of the wing and the interior of the quill (after opening it longitudinally) were analyzed. Natural nests were also examined and mites found associated with them were manually assembled. Sampling was random and eventual, for only accidentally dead animals were used, which were sent over to Laboratório de Entomologia do Departamento de Parasitologia, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP). Specimens were obtained from domestic livestocks (domestic chicken, cockatiel and budgerigar) and from synanthropic (domestic dove, eared dove, common-ground dove and other.) and wild (hummingbirds and other.) birds. Material voucher was deposited in the collection of Departamento de Parasitologia, IB, UNICAMP. Some of the conclusions obtained follow: Free-living stages [deutonymph (hipopus), tritonymph, ovigerous female, and heteromorphic male] of Hipodectes propus are described for the first time in Brazil, found in the nests of Zenaida auriculata (DES MURS), which is also recorded as a new host. Three species of genus Pellonyssus YUNKER & RADOVSKY, which are bloodsucking nest mites, are reported: P.gorgasi, P. marui e P. reedi. Also found for the first time in wings and tail feathers of cockatiel Nymphicus hollandicus (KEER), is the pterolichid mite Nymphicilichus perezae MIRONOV & GALLOWAY. In budgerigars Melopsittacus undulatus (SHAW) we also report for the first time in Brazil occurrence of the feather mites, Sideroferus lunula (ROBIN) and Dubininia melopsittaci (GAUD & ATYEO, 1987). Hyperparasitical-phoretical association was observed between pregnant females and embrionated eggs of Myialges anchora TROUESSART, 1906 and hippoboscid fly, Pseudolynchia canariensis (MACQUART, 1840). The association between quill mites and the domestic hen of rusting breeding, Gallus gallus domesticus L. is described relatively common species, Syringophilus bipectinatus HELLER, 1880, and Dermoglyphus elongatus (ROBIN & MÉGNIN, 1877), together with other two species, Paralges pachycnemis TROUESSART & MÉGNIN, 1884 and Gaudoglyphus minor (Nörner, 1882) are described for the first time in Brazil. This mite group is poorly known for birds occurring in Brazil, which indicates that an enormous effort will be needed to increase the understanding of the diversity of such extremely interesting species and its interactions / Mestrado / Mestre em Parasitologia
4

Oribatid mite (Acari:Oribatida) assemblage response to changes in litter depth and habitat type in a beech-maple forest in southwestern Quebec

Sylvain, Zachary A. January 2007 (has links)
I investigated oribatid mite assemblages in a beech-maple forest in southwestern Quebec. I first examined the effects of four forest stand types (American Beech (Fagus grandifolia) dominated, Sugar Maple (Acer saccharum) dominated, mixed deciduous and coniferous plantations) and three open site types (agricultural field, fallow pasture and unmanaged hay field) in structuring oribatid mite assemblages. My second study focused on the effects of changes in litter depth (a factor that varies by stand type) on the structure of oribatid assemblages. / Stand type was shown to be an important factor in determining oribatid mite abundances, species richness and assemblage composition. Results from the second study confirm this, but revealed no effect of changes in litter depth on oribatid mite assemblages. These findings serve to demonstrate that while examining specific environmental factors as determinants of oribatid mite diversity and distribution is important, more general factors such as habitat type cannot be ignored.
5

Oribatid mite (Acari:Oribatida) assemblage response to changes in litter depth and habitat type in a beech-maple forest in southwestern Quebec

Sylvain, Zachary A. January 2007 (has links)
No description available.
6

Phylogeny, taxonomy and species delimitation of water mites and velvet mites

Stålstedt, Jeanette January 2017 (has links)
This study is part of the Swedish Taxonomy Initiative (STI) - one of the most ambitious all taxa biodiversity inventories in the world. One of the pillars in STI is to support taxonomic research on the most neglected taxonomic groups with the aim to lift the level of knowledge of biodiversity in the country. There is still a lot to be discovered, especially in the microscopic world, and this includes mites. Many aspects of mite biology and diversity are poorly known, such as species richness, abundance, distribution, lifestyle and behavior of species. Mites inhabits all sorts of aquatic, terrestrial, arboreal and parasitic habitats, nevertheless even in well-studied systems mites are often overlooked. Despite being among the smallest of arthropods, they are of medical and economical importance and may be very abundant in the ecosystems they inhabit. This thesis focuses on Parasitengona (Acariformes: Prostigmata), one of the most diverse taxa among the arachnids. It includes the aquatic Hydrachnidia (water mites) and the terrestrial Trombidia (e.g. velvet mites, chiggers). A unifying characteristic of Parasitengona is their complex life cycle of active and inactive stages, parasitic larvae and predatory deutonymphs and adults. They typically parasitize and prey on arthropods, except the chiggers which have vertebrates as hosts. The aim of this thesis is to shed light on the phylogeny and taxonomy of Parasitengona with emphasis on the Swedish fauna. To achieve this, mites were collected from different localities throughout the country between the years 2007-2016. Water mites were sampled with a hand net. Larvae of terrestrial Parasitengona were collected with sweeping nets and sorted out from malaise trap samples from the Swedish Malaise Trap Project. To collect the adults Berlese-Tullgren extractor and pitfall traps were used as well as hand collecting and sifting with litter reducer. The material collected abroad was kindly provided through collaboration.  Methods used in the papers included morphometrics, multivariate analyses, experimental rearing, DNA extraction and sequencing, Bayesian phylogenetic analyses and molecular species delimitation. In paper I and II, we combine molecular species delimitation models and morphological data to resolve taxonomical issues. This integrative taxonomic approach of combining data resulted in Piona dispersa Sokolow, 1926 as a valid species and redescriptions, new synonyms and neotypes provided for Erythraeus phalangoides (De Geer, 1778),  E. cinereus (Dugès, 1834) and E. regalis (C.L. Koch, 1837). Based on the new inventories we produce an updated and annotated checklist of 105 terrestrial Parasitengona species for Fennoscandia in paper III, and use metadata to increase the knowledge on distribution, habitat preferences, life stages and abundance. Out of these, 20 species are new findings for the region and five are potential new species for science. In paper IV, we provide a molecular phylogeny of Parasitengona based on the genes 18S, 28S and COI for 80 taxa with a sampling focus on the terrestrial lineages. Based on the results we offer a revised higher-level classification of the group. In particular the analyses supported Tanaupodoidea Thor, 1935 as a separate superfamily, but Trombiculoidea Ewing, 1929 was not monophyletic and was synonymized, along with Chyzerioidea Womersley, 1954, with Trombidioidea Leach, 1815. / <p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Manuscript. Paper 4: Manuscript.</p><p> </p>
7

Phylogeny of Ameronothroidea in the south polar region and the phylogeography of selcted species on sub-antarctic Marion Island

Mortimer, Elizabeth 03 1900 (has links)
Thesis (DPhil)--University of Stellenbosch, 2008. / ENGLISH ABSTRACT: Sub-Antarctic islands represent the only mid to high latitude terrestrial biomes in the Southern Hemisphere. These islands have various geological origins and histories, well-preserved terrestrial ecosystems and high levels of species endemism. In an attempt to understand the evolution and biogeography of terrestrial taxa in the South Polar Region, the first broad-scale molecular phylogeny was constructed for the unique terrestrial group, the ameronothroid mites (genus Halozetes (Oribatida)), collected from sub-Antarctic and Maritime Antarctic localities. Phylogenetic analyses based on a combined mitochondrial (cytochrome oxidase subunit I (COI)) and nuclear (histone-3 (H3)) sequence dataset indicated that the evolution of these mites were habitat specific (i.e. intertidal, supralittoral and terrestrial). Notwithstanding criticisms levelled against a molecular clock, the mites were evolutionary young (<10myo), contrary to their status as an ancient group predating Gondwana fragmentation. Biogeographic analyses indicated a complex pattern mainly sculpted by multiple independent dispersal events across the Antarctic Polar Frontal Zone similar to previous findings for other marine and terrestrial taxa. Also, the molecular phylogeny displayed considerable discourse with contemporary taxonomy suggesting the need for taxonomic revisions and reassessment of morphological characters. Sub-Antarctic Marion Island, the larger of the two islands comprising the Prince Edward Island archipelago (PEI), has experienced extensive glaciation and volcanism. To assess the impact of historical events (volcanism (including recent eruptions) and glaciation) and contemporary mechanisms (gene flow) on the genetic spatial distribution of species from Marion Island, two mite species namely Eupodes minutus (Prostigmata) and Halozetes fulvus (Oribatida) as well as a single plant species, Azorella selago (Apiaceae), were selected as model organisms. For independent phylogeographic analyses, mitochondrial sequence data (COI) were obtained for both mite species, while chloroplast sequence (trnH-psbA) and amplified fragment length polymorphism (AFLP) data were generated for the cushion plant, A. selago. Since A. selago is typified by two growth forms namely discrete cushions and continuous mats, it was essential to examine the growth dynamics prior to phylogeographic analyses. The sequence and fragment data indicated that both mite and plant species were significantly substructured across Marion Island. Manual comparisons indicated unique populations on the western (Kaalkoppie for H. fulvus, La Grange Kop for E. minutus and Mixed Pickle for A. selago), eastern (Bullard Beach for H. fulvus and Kildalkey Bay for E. minutus), northern (Middelman and Long Ridge for H. fulvus) and southern side (Grey Headed for H. fulvus and Watertunnel for A. selago) of the island. Importantly, the western side had unique localities for all species. Interestingly, based on the H. fulvus data, the western populations were relatively young, characterized by high migration rates, small effective (female) population sizes with no isolation-by-distance. The opposite scenario was found for the eastern populations. This spatial genetic structure described for species on Marion Island can be ascribed to both historical events and environmental conditions. These areas with their unique genetic composition are of special conservational concern; consequently this research will contribute to an active management plan for PEI, South Africa’s only Special Nature Reserve. / AFRIKAANSE OPSOMMING: Sub-Antarktiese eilande verteenwoordig die enigste terrestriële bioom in die middel tot hoër breedtegrades van die Suidelike Halfrond. Hierdie eilande besit ‘n verskeidenheid van geologiese oorspronge en geskiedenisse, goed-bewaarde terrestriële ekosisteme en hoë vlakke van endemisme. In ‘n poging om die evolusie en biogeografie van terrestriële taksa in die Suid Pool Area te verstaan, is die eerste grootskaalse molekulêre filogenie saamgestel vir ‘n unieke terrestriële groep, die ameronothoïed miete (genus Halozetes (Oribatida: Ameronothroidea)), vanaf menigte sub-Antarktiese en Maritime Antarktiese lokaliteite. Filogenetiese analises gebaseer op die saamgestelde mitochondriale (sitokroom oksidase subeenheid I (COI)) en nukluêre (histoon-3 (H3)) basispaarvolgordes het aangedui dat die evolusie van hierdie miete habitat spesifiek is (m.a.w inter-gety, supralitoraal en terrestrieël). Ongeag die kritiek teenoor ‘n molekulêre klok, is hierdie miete evolusionêr jonk (<10mjo), wat teenstrydig is met hulle status as ‘n antieke groep wat terugdateer voor Gondwana fragmentasie. Biogeografiese analises het ‘n komplekse patroon aangedui wat grotendeels gekarakteriseer word deur menigte onafhanklike verspreidingsgebeurtenisse bo-oor die Antarktiese Polêre Frontale Zone, wat ooreenstemmend is met vorige bevindinge vir ander mariene en terrestriële taksa. Die molekulêre filogenie het ook aansienlik verskil van die tradisionele taksonomie, dus is taksonomiese aanpassings en herklassifisering van morfologiese karakters noodsaaklik. Sub-Antarktiese Marion Eiland, die groter eiland van die Prins Edward eilandgroep (PEI), het uitermate glasiasie en vulkanisme ondervind. Om die impak van historiese gebeurtenisse (vulkanisme (insluitend onlangse uitbarstings) en glasiasie) en kontemporêre meganismes (geenvloei) op die genetiesgespasieërde verspreiding van spesies vanaf Marion Eiland te bepaal, was twee mietspesies naamlik Eupodes minutus (Prostigmata) en Halozetes fulvus (Oribatida) asook ‘n enkele plantspesie, Azorella selago (Apiaceae), gekies as model organismes. Vir onafhanklike filogeografiese analises, was die mitochondriale basispaarvolgorde (COI) vir beide mietspesies bepaal, terwyl chloroplast basispaarvolgorde (trnH-psbA) asook geamplifiseerde fragmentlengte polimorfisme (AFLP) data gegenereer was vir die kussingplant, A. selago. Aangesien A. selago gekenmerk word deur twee groeivorme, naamlik diskrete kussings en aaneenlopende matte, was dit noodsaaklik om eers die groeidinamika van die plant te ondersoek alvorens ‘n filogeografiese studie kon geskied. Die basispaarvolgordebepalings en fragmentdata het aangedui dat beide mietspesies sowel as die plantspesie betekenisvolle substruktuur vertoon regoor Marion Eiland. Informele vergelykings het unieke populasies aangedui op die westelike (Kaalkoppie vir H. fulvus, La Grange Kop vir E. minutus en Mixed Pickle vir A. selago), oostelike (Bullardstrand vir H. fulvus en Kildalkeybaai vir E. minutus), noordelike (Middelman en Long Ridge vir H. fulvus) en suidelike kant (Grey Headed vir H. fulvus en Watertunnel vir A. selago) van die eiland. Die westelike kant besit dus unieke lokaliteite vir al die spesies. Interressantheidhalwe het die H. fulvus data getoon dat die westelike populasies relatief jonk is en gekarakteriseer word deur hoë migrasiesyfers en klein effektiewe (vroulike) populasiegroottes met geen isolasie-oor-afstand nie. Die resultate vir die populasies aan die oostelike kant van die Marion Eiland was presies teenoorgesteld. Dié beskryfde substruktuur vir die spesies op Marion Eiland is afkomstig van beide historiese gebeurtenisse asook omgewingstoestande. Hierdie areas met hul unieke genetiese samestelling, is belangrik vir natuurbewaring. Hierdie navorsing sal bydra tot die bestuursriglyne van PEI, Suid Afrika se enigste Spesiale Natuurreservaat.

Page generated in 0.0466 seconds