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  • 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.
101

Coleópteros (insecta) associados às estruturas reprodutivas de espécies florestais arbóreas nativas no Estado de São Paulo. / Coleoptera (insecta) associated to the reproductive structures of native forest tree species in the state of São Paulo, Brazil.

Alexsandro Zidko 04 April 2002 (has links)
As espécies florestais arbóreas nativas apresentam interações com coleópteros que se desenvolvem no interior das estruturas reprodutivas. Foram estudadas as seguintes espécies florestais arbóreas nativas e identificados os coleópteros a elas associados: Pterogyne nitens Tul. (amendoim-bravo) - Tricorynus sp. (Anobiidae) e Ormiscus sp. (Anthribidae); Stryphnodendron adstringens (Mart.) Cov. (barbatimão) - Acanthoscelides sp. (Bruchidae); Cassia grandis L. f. (cássia-grande) - Pygiopachymerus lineola (Bruchidae); Tabebuia alba (Cham.) Sandwith (ipê-amarelo) - Sitophilus linearis (Curculionidae); Hymenaea courbaril var. stilbocarpa (Hayne) Lee & Lang (jatobá) - Tricorynus sp. (Anobiidae); Chorisia speciosa (A. St. - Hil.) Dawson (paineira) - Lonchophorus obliquus (Curculionidae); Caesalpinia ferrea var. leiostachya Benth. (pau-ferro) - Pityophthorus sp. (Scolytidae); Aspidosperma polyneuron Müll. Arg (peroba) - Tricorynus sp. (Anobiidae) e Rhinochoenus stigma (Curculionidae); Enterolobium contortisiliquum (Vell.) Morong (timbó) - Stator pacarae(Bruchidae). / This paper deals with the identification of Coleoptera (species and family) associated to the reproductive structures of the following native forest tree species: Pterogyne nitens Tul. ("amendoim-bravo") - Tricorynus sp. (Anobiidae) and Ormiscus sp. (Anthribidae); Stryphnodendron adstringens (Mart.) Cov.("barbatimão") - Acanthoscelides sp. (Bruchidae); Cassia grandis L. f. ("cássiagrande") - Pygiopachymerus lineola (Bruchidae); Tabebuia alba (Cham.) Sandwith ("ipê-amarelo") - Sitophilus linearis (Curculionidae); Hymenaea courbaril var. stilbocarpa (Hayne) Lee & Lang ("jatobá") - Tricorynus sp. (Anobiidae); Chorisia speciosa (A. St. - Hil.) Dawson ("paineira") - Lonchophorus obliquus (Curculionidae); Caesalpinia ferrea var. leiostachya Benth. ("pau-ferro") - Pityophthorus sp. (Scolytidae); Aspidosperma polyneuron Müll. Arg ("peroba") - Tricorynus sp. (Anobiidae) and Rhinochoenus stigma(Curculionidae); Enterolobium contortisiliquum (Vell.) Morong ("timbó") - Stator pacarae (Bruchidae).
102

Caracterização evolutiva das serina peptidases digestivas em insetos holometábolos / Evolutionary characterization of digestive serine peptidases in holometabolous insects

Renata de Oliveira Dias 07 August 2014 (has links)
Tripsinas e quimotripsinas são classes de serina peptidases amplamente estudadas e fortemente responsáveis pela digestão proteica, pela clivagem de ligações peptídicas no lado carboxila de L-aminoácidos de cadeia lateral básica e hidrofóbica, respectivamente. Três processos regulam finamente a ação dessas peptidases: secreção, ativação do precursor (zimogênio) e o sítio de reconhecimento do substrato. No presente trabalho é apresentada uma análise filogenética detalhada das tripsinas e quimotripsinas de três ordens de insetos holometábolos, revelando características divergentes nas enzimas de Lepidóptera em relação a Coleóptera e Díptera. Em particular, o sub-sítio S1 das tripsinas foi observado como mais hidrofílico em Lepidóptera do que em Coleóptera e Díptera, enquanto os sub-sítios S2-S4 parecem mais hidrofóbicos, sugerindo diferente preferências pelo substrato. Além disso, Lepidóptera mostrou um grupo de tripsinas bastante específico a um grupo taxonômico, compreendendo somente proteínas de espécies da família Noctuidae. Evidências de eventos de auto-ativação facilitada foram também observadas em todas as ordens de insetos estudadas, com as características do motivo de ativação do zimogênio complementárias ao sítio ativo das tripsinas. Em contraste, as quimotripsinas de insetos não parecem ter uma história evolutiva peculiar com respeito a, por exemplo, seus homólogos em mamíferos. Em geral, os presentes resultados sugerem que a necessidade de uma rápida taxa de autoativação fez os insetos holometábolos selecionarem grupos especializados de tripsinas com altas taxas de auto-ativação e também destacam que a evolução das tripsinas culminou em um grupo especializado de enzimas em Lepidóptera. / Trypsins and chymotrypsins are well-studied classes of serine peptidases largely responsible for the digestion of proteins by cleavage of the peptide bond at the carboxyl side of basic and hydrophobic L-amino acids, respectively. Three processes mainly regulate the action of these peptidases: secretion, precursor (zymogen) activation and substrate-binding site recognition. In the present work is presented a detailed phylogenetic analysis of trypsins and chymotrypsins in three orders of holometabolous insects revealing divergent characteristics in the Lepidoptera enzymes in relation to Coleoptera and Diptera. In particular, trypsin subsite S1 was observed to be more hydrophilic in Lepidoptera than in Coleoptera and Diptera, whereas subsites S2-S4 appeared more hydrophobic, suggesting different substrate preferences. Furthermore, Lepidoptera displayed a very specific taxonomic trypsin group, only encompassing proteins from the Noctuidae family. Evidences for facilitated trypsin auto-activation events were also observed in all the insect orders at hand, with the characteristic zymogen activation motif complementary to the trypsin active site. In contrast, insect chymotrypsins did not seem to have a peculiar evolutionary history with respect to e.g. their mammal counterparts. Overall, the present findings suggest that the need for fast digestion made holometabolous insects evolve specialized groups of trypsins with high autoactivation rates and highlight that the evolution of trypsins culminated in a specialized group of enzymes in Lepidoptera.
103

Utility of DNA barcodes in identification and delimitation of beetle species, with insights into COI protein structure across the animal kingdom

Pentinsaari, M. (Mikko) 26 April 2016 (has links)
Abstract Species are the fundamental units of biological diversity, but their identification and delimitation is often difficult. The difficulties are pronounced in diverse taxa such as insects. DNA barcodes, short standardized segments of the genome, have recently become a popular tool for identifying specimens to species, and are increasingly used as one of the sources of information for species delimitation. In this thesis, I studied the utility of DNA barcodes in species identification and delimitation in beetles (Coleoptera). Beetles are one of the most diverse animal groups, with nearly 400 000 known species. The Nordic beetle fauna is among the most thoroughly studied on the planet, providing excellent conditions for these studies. I also approached barcode sequences from a new angle, exploring amino acid variation and its connections to life history in a sample of the entire animal kingdom. I also studied variation and evolution at the amino acid level in large-scale samples of beetles and moths & butterflies (Lepidoptera). DNA barcodes proved to be a feasible tool for identifying species of Nordic beetles: depending on the criteria for successful identification, 95-98% of specimens could be identified to the species level based on DNA barcodes. Regardless of the delimitation method used, approximately 90% of the currently accepted species were perfectly recovered based on barcode data, and simple rules for forming consensus between delimitations improved the fit between species and barcode clusters even further. Several species that were split into two or more sequence clusters apparently include species new to science that have been previously overlooked. This conclusion is supported by preliminary morphological analysis. The study on amino acid variation revealed both a general pattern of structural conservation throughout the animal kingdom, and some interesting amino acid substitutions with potential to affect enzymatic function. Amino acid variation was more extensive in Coleoptera than in Lepidoptera, potentially due to differences in selection pressure and patterns of molecular evolution in the barcode region between the two orders. / Tiivistelmä Laji on luonnon monimuotoisuuden perusyksikkö, mutta lajien tunnistaminen ja rajaaminen on usein vaikeaa. Vaikeudet korostuvat erityisesti hyvin monimuotoisissa eliöryhmissä kuten hyönteisissä. DNA-viivakoodit ovat lyhyitä standardoituja DNA-sekvenssejä, joiden käyttö lajien tunnistamisessa sekä yhtenä tiedon lähteenä lajien rajaamisessa on viime aikoina yleistynyt nopeasti. Tutkin väitöskirjatyössäni DNA-viivakoodien soveltuvuutta lajinmääritykseen ja lajien rajaamiseen kovakuoriaisilla. Kovakuoriaiset ovat yksi maailman lajirikkaimmista eliöryhmistä: lajeja on kuvattu lähes 400000. Pohjois-Euroopan lajisto tunnetaan koko maailman mittakaavassa poikkeuksellisen hyvin, mikä tarjoaa erinomaiset edellytykset tutkia DNA-viivakoodeihin liittyviä kysymyksiä kuoriaisilla. Tutkin DNA-viivakoodeja myös kokonaan uudesta näkökulmasta, selvittäen aminohappotason muuntelua koko eläinkunnan kattavassa otoksessa, sekä laajalla perhos- ja kuoriaisaineistolla. DNA-viivakoodit osoittautuivat erinomaiseksi työkaluksi lajinmääritykseen: riippuen onnistuneen määrityksen kriteereistä 95–98 % kuoriaislajeista voitiin tunnistaa luotettavasti viivakoodien perusteella. Käytetystä menetelmästä riippumatta noin 90 % nykykäsityksen mukaisista lajeista voitiin rajata viivakoodien perusteella oikein, ja soveltamalla yksinkertaisia konsensus-sääntöjä yhteensopivuus lajien ja viivakoodiklustereiden välillä kasvoi entisestään. Useat kuoriaislajit, jotka jakautuivat kahteen tai useampaan viivakoodiklusteriin, sisältävät alustavien morfologisten tutkimusten perusteella aiemmin huomaamatta jääneitä uusia lajeja. Aminohappo- ja proteiinitason tutkimus osoitti, että viivakoodijakson koodaaman proteiinin rakenne on yleisesti ottaen konservoitunut kautta eläinkunnan. Havaitsin kuitenkin myös useita kiinnostavia aminohappo-muutoksia, jotka saattavat vaikuttaa entsyymitoimintaan. Aminohapposekvenssi muuntelee kuoriaisilla paljon enemmän kuin perhosilla, mahdollisesti johtuen taksonien välisistä eroista molekyylievoluutiossa ja viivakoodisekvenssiin kohdistuvassa valintapaineessa.
104

Larvální morfologie tribu Goliathini (Coleoptera: Cetoniinae) a její využití při studiu fylogeneze zlatohlávků. / Larval morphology of Goliathini (Coleoptera: Cetoniinae) and its contribution towards the understanding of the group's evolution.

Kouklík, Ondřej January 2017 (has links)
1 Abstract Currently there are almost 4000 described species of rose chafers (Scarabaeidae: Cetoniinae) but larvae of less than 200 species are described. In this work we studied larval morphology of 86 species belonging to 58 genera with focus on the tribe Goliathini. The larvae of 21 genera were studied for the first time. 77 morphological characters on head, mouth parts, legs and thoracal and abdominal segments were studied. This resulted into large matrix of morphological characters, which were further tested in separate phylogenetical analyses. A checklist of studied characters and their states and also large databasis of photographs of the characters are also amongst the results of the thesis. Five independent datasets were tested, three were based singly on morphology, one on molecular sequences and one on a combined dataset. The phylogenetic analysis was made by three methods, maximum parsimony, maximum likelihood and bayesian interference. Eleven different phylogenetic trees were obtained as a result, based on which we tried to reconstruct the relationships between the inner groups of Cetoniinae with focus on relationship of subtribes of tribe Goliathini. Monophyly of the tribe Goliathini as well as some other groups could not be confirmed, as well as the alleged basal position of the genus...
105

Phylogeography of Scarabaeus (Pachysoma) Macleay (Scarabaeidae: Scarabaeinae)

Sole, Catherine L. 30 January 2006 (has links)
Scarabaeus (Pachysoma) consists of 13 flightless dung beetle species endemic to the arid west coast of southern Africa. Scarabaeus (Pachysoma) are unique in their feeding and foraging habits, in that they randomly search for dry dung/detritus which, when found, is dragged forwards, and buried in a pre-constructed holding chamber, as opposed to the convention of rolling it backwards. This action is repeated to provision the chamber after which the nest is expanded to below the moisture line to allow the stored food to re-hydrate. Poor vagility, taxonomic contention - seen in Scarabaeus taxonomy - and conservation concern, made Scarabaeus (Pachysoma) an ideal group of beetles to study both the phylogenetics and potential influences that anthropogenic and environmental changes have had on structuring the species and populations thereof. Both molecular and morphological data were used as individual datasets and combined in a total evidence approach. Biogeographic inferences were made based on recent detailed Namib biogeography and the ages of the species were estimated using the molecular clock method. A phylogeographic study was done on three of the species of Scarabaeus (Pachysoma) – S. (P.) hippocrates, S. (P.) gariepinus and S. (P.) denticollis - that had previously shown south-north morphological clinal variation. Lastly, an attempt was made to isolate microsatellite loci for Scarabaeus, in the hope of characterising genetic diversity within and between populations of the same species. Scarabaeus (Pachysoma) was found to be monophyletic within Scarabaeus and was therefore classified as a derived subgenus thereof. Morphologically Scarabaeus (Pachysoma) was shown to have 13 species while at a molecular level strong resolution for 11 of the 13 was obtained. S. (P.) hippocrates and S. (P.) glentoni formed a species complex the hippocrates/glentoni complex. The combined phylogenetic tree showed good overall support for all 13 species. Both the morphological and molecular data partition phylogenies show congruence with the combined phylogeny, lending support for combining datasets. Scarabaeus (Pachysoma) appears to have arisen 2.9 million years ago. The formation of advective fog is a consistent water source for Desert dwelling organisms and appears to be associated with Scarabaeus (Pachysoma) radiation into inhospitable areas. Analysis of gene flow revealed large amounts of south-north movement, lending support for movement of psammophilous taxa with their substratum, the barchan dune. Population demographics of the three species, S. (P.) hippocrates, S. (P.) gariepinus and S. (P.) denticollis, chosen for this study differed greatly except in areas of geographic similarity. Major rivers appear to have acted as gene barriers, allowing for distinct genetic entities to be identified within the three species. Phylogeographic partitioning was supported by an AMOVA analysis. All three species were shown to have undergone historical population expansion dating back to the Pleistocene era. Nested Clade Analysis indicated that allopatric speciation; isolation by distance and continuous range expansion could be the factors having affected overall population structure. Recent events show that human induced factors, environmental barriers and reduced vagility have influenced the species population structure. Four potentially polymorphic loci were isolated for Scarabaeus using the FIASCO protocol. Identification of at least one additional locus is needed in order to obtain statistical significance for future studies directed at uncovering recent population dynamics. / Thesis (PhD (Entomology))--University of Pretoria, 2007. / Zoology and Entomology / unrestricted
106

Stratigraphic and palaeoenvironmental observations in the deposits of a postglacial kettle hole, in the county of Västernorrland

Kourela, Genofeva Eva January 2020 (has links)
The increased human impact on the environment and climate after the retreat of the Last Glacial has strengthened its importance in the region of Västernorrland where Mesolithic sites are evident. This study focuses on a multiproxy analysis, where archaeological and natural science methods are combined to test several techniques in a peat sample. The origin of the peat sample is coming from the formation of a postglacial kettle hole situated near to Mesolithic sites. The aim of this thesis is twofold. Firstly, to estimate the value and the weakness of each method as also the combination of multiple results. Secondly, to reconstruct the palaeoenvironment including the detection of possible indications from past cultures. To begin with, the peat sample was collected from a kettle hole near Lillsjön lake, see (fig. 1) in 2010. The total depth of the peat sample was 80 cm and after its sampling, it was placed in a cold storage room until the spring of 2019, when analysis was conducted. Initially, a theoretical background will be presented as well as information for the area of study in the section of Scientific background. Moreover, a short theory is going to be given for the formation of the landscapes in cold environments as also the validity of beetle fossils with examples from previous case studies. After the theory part, all the methods are specified with results and appropriate diagrams and tables. After the analysis, the discussion will follow by combining all the methods and give potential theories for the reconstruction of the palaeoenvironment. The discussion part is divided into smaller chapters and after the conclusion an appendix is given with fossil photographs that were taken during the identification, see (fig.15,16,17).
107

Evoluce, biogeografie a systematika mechových dřepčíků (Coleoptera: Chrysomelidae: Galerucinae) / Evolution, biogeography and systematics of moss-inhabiting flea beetles (Coleoptera: Chrysomelidae: Galerucinae)

Damaška, Albert January 2019 (has links)
Flea beetles (Alticini) are a highly diversified group of leaf beetles (Chrysomelidae) with about 8 000 known species from about 560 genera distributed worldwide except Antarctica. The major life strategy of flea beetles is external feeding on vascular plants, similarly to other leaf beetles. However, studies published during last years revealed existence of numerous different flea beetle genera feeding on mosses. Moss-inhabiting flea beetles are usually highly specialized and share similar morphological characteristics, including flightlessness, compact body shape and modified antennae. However, their phylogenetic position remained unknown. In this study, I performed a phylogenetic analysis of 14 known moss- and leaf litter inhabiting flea beetle genera, included into a large dataset of various genera of flea beetles. I sequenced 2 mitochondrial and 2 nuclear genes previously used for phylogenetic analyses of Alticini. I also added numerous Neotropical external feeding alticine genera, because taxon samples from previous studies (Ge et al. 2012; Nie et al. 2017) consisted mainly of Oriental genera. Although deep divergences and phylogenetic positions of several genera were not resolved, the analysis revealed a multiple origin of moss- and leaf litter inhabitance among flea beetles. The morphologically...
108

Biology and Energetics of Tropisternus Lateralis Nimbatus (SAY) (Coleoptera: Hydrophilidae) in a Playa on the Southern High Plains of Texas and Aquatic Coleoptera Diversity from Seven Playas on the Southern High Plains of Texas

Cook, Robert E. (Robert Edward), 1969- 12 1900 (has links)
A study of the biology of Tropisternus lateralis, a hydrophilid beetle, was conducted during the flood period of a single playa on the Southern High Plains of Texas from early June 1995 through early September 1995. Mechanism of colonization, tolerance/avoidance to drought, larval density, and secondary production were analyzed. T. lateralis colonized playas from surrounding aquatic habitats and avoided drought through aerial dispersion. Once in the playa, larval density increased over time. Secondary production was 1.31 g/m2/.25 yr. In addition, aquatic Coleoptera diversity was studied in seven playas on the Southern High Plains of Texas. A total of twenty three species were identified from the study region. Nine species not reported in playa literature were identified.
109

Růst a pohlavní dimorfismus u vybraných zástupců listorohých brouků (Coleoptera: Scarabaeoidea). / Growth and sexual selection in selected representatives of scarabaeoid beetles (Coleoptera: Scarabaeoidea).

Vendl, Tomáš January 2019 (has links)
Flower chafers are well-known beetles with apparent sexual dimorphism. Yet, in contrast to other groups of scarab beetles, only little attention has been paid to various aspects of this phenomenon. It concerns also sexual dimorphism in size, which is very common in animals. Although ultimate causes of sexual size dimorphism have been extensively studied, the developmental mechanisms are still only poorly understood. We investigated proximate causes of sexual size dimorphism in several differentially dimorphic flower chafer species. We found that in highly dimorphic species the dimorphism started to develop already in the first instar and tended to accumulate through successive larval development. In contrast, the sexes in species with a relatively low dimorphism diverged in size during only one instar. Moreover, we found variability not only in when the dimorphism arises during development, but also how: sex-related differences in both the instar duration and average growth rate were the proximate causes of sexual size dimorphism. In addition, we showed that the sexes may differ also in growth trajectory - males had relatively longer period of rapid growth than females, even in cases where the absolute development times were similar in both sexes. Further, we focused on systematic survey of sexual...
110

Redes de Interacción Formadas por Coleópteros y Dípteros (Syrphidae) Saproxílicos en Oquedades Arbóreas del Bosque Mediterráneo Ibérico

Sánchez Galván, Ingrid R. 27 September 2017 (has links)
En la presente tesis doctoral se presenta un estudio profundo de los ensambles formados por insectos saproxílicos (Coleópteros y Dípteros Syrphidae) ligados a las cavidades arbóreas de quercínas ibéricas (Quercus spp). Las especies saproxílicas (coleópteros y dípteros sírfidos) conforman complejas redes ecológicas conectadas a través de diferentes interacciones de especies insecto-insecto. Nuestros hallazgos recalcan la importancia para la conservación de la comunidad entomológica saproxílica, centrar la atención en el estudio de especies clave que cumplen un papel fundamental en la organización de los ensambles al condicionar la presencia o la ausencia de otras especies o gremios de especies que se desarrollan dentro de cada oquedad (ej. especies “ingenieros del ecosistema”). Ponemos de manifiesto también la importancia que tiene la microbiota dentro la oquedad como recurso trófico de las fases larvarias acuáticas de especies de sírfidos que como adultos, son visitantes florales asiduos de las flores de nuestros bosques mediterráneos.

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