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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.
21

The feeding and nutrition of certain Hemiptera and Homoptera

Scheel, Carl A. January 1957 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1957. / Typescript. Abstracted in Dissertation abstracts, v. 17 (1957) no. 4, p. 883. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 70-76).
22

Contributions to knowledge of water relations in Hemiptera

Goodchild, A. J. P. January 1988 (has links)
No description available.
23

Taxonomia de Cylindrostethus Mayr, 1865 (Hemiptera : Heteroptera : Gerridae) da América do Sul

Burguez Floriano, Carla Fernanda 06 August 2013 (has links)
Resumo: Gerridae Leach, 1815 é composta por 75 gêneros e mais de 700 espécies, distribuídas em oito sub famílias: Charmatometrinae, Cylindrostethinae, Eotrechinae, Gerrinae, Halobatinae, Ptilomerinae, Rhagadotarsinae e Trepobatinae (sensu Andersen 1975). Cylindrostethinae é composta pelos gêneros Platygerris, Potamobates e Cylindrostethus (Hungerford & Matsuda 1960). As espécies de Cylindrostethus diferenciam-se facilmente dos demais gerrídeos por ser longas e cilíndricas (Drake & Harris 1952). Atualmente são registradas dezoito espécies, ocorrendo na região paleotropical e neotropical. Na América do Sul ocorrem nove espécies: C. bassleri Drake, 1952; C. bilobatus Kuitert, 1942; C. erythropus (Herrich - Schaffer, 1850); C. hungerfordi Drake & Harris, 1934; C. linearis (Erichson, 1848); C. palmaris Drake & Harris, 1934; C. podargus Drake, 1958; C. regulus (White, 1879) e C. stygius Drake, 1961. Foram estudados 285 espécimes, incluindo representantes das nove espécies registradas, com seus respectivos tipos, exceto de C. erythropus, que não foi encontrado. No presente trabalho, as espécies de Cylindrostethus Sul-americanas foram revisadas com base na morfologia externa, principalmente a genitália dos machos. A partir do exame do material, as espécies foram redescritas, descritas e ilustradas. Duas novas espécies foram descritas, C. stygius é sinonimizada com C. podargus, e C. linearis é sinonimizada com C. erythropus. São apresentadas chave de identificação, mapas, desenhos e fotos.
24

Mirmecomorfismo em alguns hemipteros e aranhas

Oliveira, Paulo Sergio Moreira Carvalho de, 1957- 28 June 1982 (has links)
Orientador: Woodruff W. Benson / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-07-16T08:50:42Z (GMT). No. of bitstreams: 1 Oliveira_PauloSergioMoreiraCarvalhode_M.pdf: 10502578 bytes, checksum: 74d526100ba3f66565c8d1de52cc8378 (MD5) Previous issue date: 1982 / Resumo: Foram estudados alguns hemípteros Alydidae (ninfas de Hyalymenus) e aranhas (Salticidae, Clubionidae e Aphantochilidae) mirmecomórficos do norte e sudeste brasileiros.As ninfas de Hyalymenus mimetizam espécies de formigas de diferentes cores e tamanhos de acordo com seus estadios. As adaptações morfológicas mais importantes,para o mimetismo de formigas, nas ninfas de H.limbativentis e H. tarsatus,são (1) região cervical e "cintura" finas; (2)corpo, patas e antenas estreitos; (3) abdome globoso e constricto anteriormente e (4) tegumento brilhante e piloso. O deslocamento rápido em ¿zigue-zague¿, a constante agitação das antenas e o comportamento de elevar e abaixar o abdome são as semelhanças mais evidentes entre as ninfas destes hemípteros e seus modelos. As ninfas miméticas foram observadas tanto de dia como à noite alimentando-se, junto com formigas, sobre frutos de algumas plantas. Hyalymenus adultos, que possuem a morfologia típica de hemípteros, são encontrados alimentando- se nas plantas principalmente à noite, e foram atacados por Camponotus spp. em cativeiro. Por outro lado, as ninfas miméticas foram atacadas por estas formigas tanto em cativeiro como no campo. Experimentos em laboratório mostra ram,que as ninfas miméticas gozam de uma certa proteção contra ataques de insetos predadores, como mantídeos e reduviídeos. ...Observação: O resumo, na íntegra, poderá ser visualizado no texto completo da tese digital / Abstract: Some myrmecomorphic Alydidae hemipterans (nymphs of Hyalymenus) and spiders (Salticidae, Ciubionidae and Aphantochilidae) from north and southeast Brazil were studied. Nymphs of Hyalymenus mimic ant species of different colors and sizes according to their instars. The main morphological adaptations for ant-mimicry in nymphs of H. limbativentris and H. tarsatus are the following: (1) cervical region and waist are narrow; (2) thin body, legs and antennae; (3) globose and anteriorly constricted abdomen; (4) shiny and pilose integurnent. The rapid ¿zig-zag¿" locomotion, the constantly agitating antennae and the behavior of rnoving up and down the abdomen are the most evident resemblances between mimetic nymphs and their models. Mimetic nymphs were observed both day and night feeding on fruits of some plants in the company of ants. Adult Hyalymenus, which have the typical hemipteran morphology, are found mainly at night feeding on plants, and were attacked by Camponotus spp. under captivity. However, mimetic nymphs were not attacked by these ants both under captivity and in the field. Laboratory experiments showed that mimetic nymphs gain some protection against attacks of predatory insects such as mantids and reduviids. On the other hand, adult Hyalymenus were attacked by these predators under the same conditions. ...Note: The complete abstract is available with the full electronic digital thesis or dissertations / Mestrado / Ecologia / Mestre em Ciências Biológicas
25

“Especies de Aphididae (Orden: Hemiptera) encontrados en cultivos en el distrito de Asia”

Ascenzo Battistini, Alessandra Milagros January 2016 (has links)
Los áfidos (Hemiptera: Aphididae) son insectos fitófagos, de tamaño pequeño, se pueden presentar en su forma alada o áptera, son considerados una plaga que afectan diversos cultivos agrícolas y ornamentales. Algunas especies pueden ser transmisores de virus que causan enfermedad en las plantas. Por lo general se encuentran en zonas tropicales. Este estudio nos ayudará a identificar las diversas especies de áfidos encontrados en cultivos del distrito de Asia, Cañete para poder ampliar el estudio de afidofauna peruana. Los áfidos de este trabajo se colectaron en plantas de interés económico y ornamental, tales como manzana, níspero, plátano, naranja, cucarda, hemerocallis, papiro, molle, tomate y granada. Se reportan nueve especies de àfidos en el distrito de Asia, Provincia de Cañete, Perú. Las especies fueron: Aphis craccivora,Aphis gossypii, Aphis nasturtii, Aphis spiraecola, Aphis punicae, Myzus hemerocallis, Pentalonia nigronervosa, Toxoptera aurantii y Schizaphis rotundiventris. Cuatro de ellas se registraron por primera vez para el distrito de Asia, Cañete, Aphis nasturtii, Aphis punicae, Pentalonia nigronervosa y Schizaphis rotundiventris.Aphids (Hemiptera: Aphididae) are phytophagous insects with small size, we can found them alate or apterous forms. The aphids are a pest that affect many crops. Some species could be virus transmitters that cause plants disease. This study could help us to identificate the diversity of aphid species founding in crops from Asia, Cañete so we can amplify the study of peruvian aphid fauna. Plants aphids of this study were collected in plants with economical and ornamental interest like apple, loquat, banana, orange, hibiscus, lily, papyro, molle, tomato and pomengranate. Nine species of aphids from Asia, Cañete in Peru are reported. The following species were: Aphis craccivora, Aphis gossypii, Aphis nasturtii, Aphis spiraecola, Aphis punicae, Myzus hemerocallis, Pentalonia nigronervosa, Toxoptera aurantii y Schizaphis rotundiventris. Four of them were registered for the first time in Asia, Cañete, Aphis nasturtii, Aphis punicae, Pentalonia nigronervosa y Schizaphis rotundiventris.
26

Specific and seasonal variation in survival and sodium balance at low pH in five species of waterboatmen (Hemiptera: Corixidae) ?

Needham, Karen Merrie January 1990 (has links)
Sodium balance and mortality rates were examined in five species of adult waterboatmen (Hemiptera: Corixidae) exposed to neutral and low pH waters. The five species were chosen to reflect a wide range of pH conditions in waters where they naturally occur. Cenocorixa bifida and C. expleta normally inhabit high pH waters, whereas C. blaisdelli and Hesperocorixa atopodonta can be found most often at neutral pH. Sigara omani occur in acidic waters. Haemolymph [Na], whole-body [Na], and sodium influx rates were recorded during exposures of 6-9 days at pH 7.0, 4.5, and 3.0. C. blaisdelli and H. atopodonta were studied throughout the year (spring, summer, and fall) . C. bifida and C. expleta were examined in the fall, while S. omani were tested in the spring. Overall, these corixids appeared to be tolerant of short-term exposure to low pH. Mortality for all species remained below 50% in both neutral and acidic pH levels throughout the year. Additionally, differences in haemolymph [Na], whole-body [Na], and sodium influx rates from pH 7.0 to either pH 4.5 or 3.0 were rarely significant. However, both inter- and intraspecific variation in sodium balance over the range of pH levels tested were apparent. Most notably, C. blaisdelli and H. atopodonta exhibited their highest concentrations of haemolymph and whole-body Na in the summer, under both natural conditions and in the laboratory at all pH levels. For C. blaisdelli, summer was also the time of highest mortality, with mortality increasing as pH was lowered. The observed correlation between high haemolymph/whole-body [Na] and high mortality in the summer appears to result from a relatively large decrease in haemolymph and whole-body [Na] when bugs were exposed to pH 3.0, at a time when these values were initially high. Fall was the season of lowest haemolymph/whole-body [Na], and also of lowest mortality, for both C. blaisdelli and H. atopodonta. Interspecific variation in the ability to tolerate low pH did not appear to reflect variation in the pH of water these bugs normally inhabit. Of the five species tested, H. atopodonta appeared best able to maintain internal homeostasis under acidic conditions, despite being common to neutral waters. Haemolymph [Na], whole-body [Na], and sodium influx rates did not change significantly from pH 7.0 to pH 3.0 in any season. Furthermore, C. blaisdelli, which was collected from the same pond as H. atopodonta, seemed to be least able to regulate internal milieu in low pH waters. In C. blaisdelli, exposure to pH 3.0 usually resulted in decreased haemolymph and whole-body [Na], relative to values recorded in those individuals exposed to pH 7.0. The difference in the size of these two species (H. atopodonta is approximately twice that of C. blaisdelli) may account for the observed variations in their respective sodium balance at low pH. / Science, Faculty of / Zoology, Department of / Graduate
27

Taxonomy and evolution of the Orthotyline genus Lopidea (Heteroptera: miridae)

Asquith, Adam 29 June 1990 (has links)
The genus Lopidea Uhler is revised for America north of Mexico. The relationship of Lopidea to other orthotyline genera is discussed and it is proposed that the genus Ilnacora Reuter is the sister group of Lopidea. Forty-eight species of Lopidea are recognized in North America, one of which is described as new. The following synonymies are created (junior names first): Lopidea navajo Knight = L. arizonae Knight; L. chelifer Knight = L. balli Knight; L. paddocki Knight and L. deserta Knight = L. bullata Knight; L. trispicata Knight = L. chandleri Moore; L. burkei Knight= L. confraterna (Gibson); L. arkansae Knight and L. biselli Knight = L. davisi Knight; L. denmani Knight and Schaffner= L. falcicula Knight; L. mohave Knight = L. garryae Knight; L. amorphae Knight and L. wisteriae Chandler= L. hesperus (Kirkaldy); L· marginalis (Reuter) = L. instabilis (Reuter); L. texana Knight, L. polingorum Knight and L. matamorensis Knight = L. major Knight; L. drakei Knight = L. marginata Uhler; L. phlogis Knight, L. petalostemi Knight and L. johnstoni Knight = L. minor Knight; Lopidea raineri Knight, Lopidea sculleni Knight, Lopidea rolfsi Knight and Lopidea wilcoxi Knight = Lopidea nigridia nigridia Uhler; Lopidea nigridea hirta Van Duzee, Lopidea usingeri Van Duzee, Lopidea discreta Van Duzee, Lopidea fallax Knight, Lopidea nicholi Knight, Lopidea yakima Knight, Lopidea audeni Knight, Lopidea eriogoni Knight, Lopidea calcaria Knight, Lopidea chamberlini Knight, Lop idea angustata Knight, Lop idea rubrofusca Knight and Lopidea flavicostata Knight and Schaffner = Lopidea nigridia aculeata Van Duzee; Lopidea medleri Akingbohungbe = Lopidea nigridia serica Knight Uhler; L. oregona Hsiao, L. calli Knight, L. knowltoni Knight, L. dawsoni Knight, L. utahensis Knight and L. yampae Knight = L. picta Knight; L. staphyleae sanguinea Knight = L.s. staphyleae Knight; L. taurula Knight, L. malvastri Knight, L. nevadensis Knight and L. fuscina Knight = L. taurina Van Duzee; L. stitti Knight and L. becki Knight = L. ute Knight. A sample of 16 speciation events derived from cladistic analyses suggests that vicariance can account for at least 50% of species generation in Lopidea. The frequency of sympatric host plant speciation may be as high as 30% and speciation by peripheral isolation has been rare if it has occurred at all. / Graduation date: 1991
28

Morfologia do sistema reprodutor masculino e dos espermatozoides em Nepomorpha e Cimicomorpha (Heteroptera) / Morphology of the male reproductive system and the spermatozoa in Nepomorpha and Cimicomorpha (Heteroptera)

Novais, Ademária Moreira 07 July 2017 (has links)
Submitted by Reginaldo Soares de Freitas (reginaldo.freitas@ufv.br) on 2017-08-23T16:12:27Z No. of bitstreams: 1 texto completo.pdf: 3646112 bytes, checksum: f1a6c721888bd52e1c4afd8a86ddb623 (MD5) / Made available in DSpace on 2017-08-23T16:12:27Z (GMT). No. of bitstreams: 1 texto completo.pdf: 3646112 bytes, checksum: f1a6c721888bd52e1c4afd8a86ddb623 (MD5) Previous issue date: 2017-07-07 / A caracterização morfológica do sistema reprodutor e dos espermatozoides tem sido reconhecida como uma fonte de caracteres para análises taxonômicas e filogenéticas. Tal caracterização tem se mostrado uma importante ferramenta na elucidação de questões da biologia reprodutiva e sistemática de diversos grupos de insetos. Nesse contexto, descrevemos, usando as microscopias de luz e eletrônica de transmissão, a morfologia do sistema reprodutor e dos espermatozoides de Martarega bentoi (Notonectidae) e Ornithocoris pallidus (Cimicidae), contribuindo com dados relevantes para a sistemática e biologia reprodutiva destas famílias, bem como para Heteroptera em geral. Os testículos de M. bentoi, possuem dois folículos espiralados e forma de caracol. A disposição lado a lado de cistos com células germinativas nas diferentes fases da espermatogênese pode ser uma característica do gênero Martarega. Cada feixe contém 64 espermatozoides, medindo aproximadamente 2.800 μm. Os espermatozoides exibem características observadas, até o momento, apenas nesta espécie: (1) acrossomo extremamente longo, com duas regiões; (2) base do núcleo terminando abruptamente com duas cavidades onde estão inseridas os derivados mitocondriais. Os espermatozoides de M. bentoi possui derivados mitocondriais bastante assimétricos e exibem duas inclusões paracristalinas e pontes ligando-os ao axonema. Entre as espécies de Notonectidae observadas até o momento, algumas características parecem ser exclusivas de M. bentoi, por exemplo, o número de espermatozoides por cisto, o tamanho do espermatozoide, a assimetria em tamanho e forma dos derivados mitocondriais e a inserção destes na base do núcleo. No segundo capítulo descrevemos o sistema reprodutor e espermatozoides de O. pallidus. Cada um dos dois testículos tem sete folículos, os quais se esvaziam de espermatozoides após a maturação sexual, quando as vesículas seminais se tornam totalmente cheias de espermatozoides. Os espermatozoides de O. pallidus exibem ultraestrutura bastante semelhante àquela de outras espécies proximamente relacionadas à Cimicidae, nos levando a supor que, aparentemente, a inseminação traumática não exerceu qualquer pressão seletiva sobre a morfologia dessas células. Contudo a sua produção em grande quantidade e restrita à fase de maturação sexual dos machos nos parece ter relação à condição hematofágica do cimicídeos. Ainda, a uniformidade morfométrica observada nos espermatozoides dessa espécie pode ser decorrente do alto risco de competição espermática somada às condições inóspitas da cavidade hemocélica da fêmea. Com base em todos os dados apresentados, podemos concluir que o sistema reprodutivo masculino e os espermatozoides dessas duas espécies estudadas, mostraram características comuns aos demais Heteroptera, outras comuns às espécies mais próximas e, ainda, algumas que, até então, são exclusivas à cada uma dessas espécies. Essas informações podem contribuir para esclarecer questões da biologia reprodutiva e sistemática desses grupos de insetos. / The morphological characterization of the reproductive system and the spermatozoa has been recognized as a source to taxonomic and phylogenetic analysis. This characterization corresponds an important tool in the elucidation of questions of the reproductive biology and systematic of several groups of insects. In this context, using light and transmission electron microscopy we described the morphology of the male reproductive system and the spermatozoa of Martarega bentoi (Notonectidae) and Ornithocoris pallidus (Cimicidae), contribution in the systematic of these two families and in general to Heteroptera. The testes of M. bentoi have two spiral format follicles and are snail shape. The side-by-side arrangement of the germinative cells in different phases of the spermatogenesis may be a characteristic of the Martarega genus. Each bundle contains 64 sperm, measuring approximately 2,800 μm. The spermatozoa exhibit characteristics observed so far only in this species: 1) extremely long acrosome with two regions; 2) base of the nucleus ending abruptly with two cavities where the mitochondrial derivatives are inserted. The spermatozoa of M. bentoi have rather asymmetric mitochondrial derivatives and exhibit two paracrystalline inclusions and bridges linking them to the axoneme. Among the species Notonectidae observed to date, some characteristics appear to be unique to M. bentoi, for example, the number of spermatozoa per cyst size of the sperm, the asymmetry in size and shape of mitochondrial derivatives and their insertion in the base of the nucleus. In the second chapter we describe the reproductive system and spermatozoa of O. pallidus. Each testicle has seven follicles which become empty of reproductive cells after sexual maturation of the male, and then the vesicles have full of sperm cells. The spermatozoa of O. pallidus show ultrastructure similar with other related species with Cimicidae, which leading us to suppose that apparently the traumatic insemination does not selective pressure in the morphology of these cells. However, the production in big quantity of spermatozoa and its restriction at the sexual maturation phase seem be related with the hematophagic condition of the cimicids. Moreover, the morphometric uniformity of the spermatozoa observed in this species may bedue to the high risk of the sperm competition, and in addition to the inhospitable condition into the female hemocellic cavity. In base at the data presented, we can conclude that the male reproductive system and the spermatozoa of the four species studied exhibited common characters with the other Heteroptera, some ones common to the nearest species, and others ones that until then are unique to each species. This information can contribute to clarify issues of reproductive biology ans systematics of these groups of insects.
29

Relacionamento filogenético de espécies pertencentes às famílias Coreidae e Pentatomidae (Heteroptera) a partir dos genes mitocondriais COI, 16S e nuclear 18S /

Souza, Hederson Vinícius de. January 2013 (has links)
Orientador: Mary Massumi Itoyama / Banca: Maria Izabel Camargo Mathias / Banca: Luis Gustavo da Conceição Galego / Banca: Eliana Morielle Versute / Banca: Hermione Elly Melara de Campos Bicudo / Resumo: Os Heteroptera apresentam particularidades, como a variação entre as espécies no número de lobos testiculares e colorações diferentes da bainha peritoneal. Além destas características, algumas espécies da família Pentatomidae possuem um dos lobos testiculares com características morfológicas e celulares diferentes dos demais lobos, levando à formação de espermatozoides com funções diversificadas. Embora apresentem inúmeras características peculiares, como as tratadas anteriormente, o modo como evoluem necessita de análises aprofundadas. Assim, o presente trabalho objetivou analisar a evolução dos caracteres números de lobos, pigmentação da bainha peritoneal, espermatozoides não fertilizantes e cariótipo, baseando-se nas reconstruções filogenéticas. Foram utilizados, como marcadores, moleculares os genes mitocondriais COI, 16S e o nuclear 18S. Foi feito o sequenciamento de parte desses genes de 25 espécies de Heteroptera, sendo 12 da Família Coreidae e 13 da família Pentatomidae. Verificou-se que sozinhos estes genes não forneceram uma inferência segura nas análises evolutivas. Com tais genes concatenados, as informações puderam se somar, porém devido à baixa consistência nos ramos, as inferências evolutivas devem ser vistas com cautela. Desse modo, esta pesquisa evidenciou a complexidade das distribuições das características testiculares e citogenéticas relatadas através da filogenia molecular. Tornando-se necessário ampliar estes estudos com novas abordagens, como a utilização de caracteres morfológicos ou outros marcadores moleculares para elucidar sua evolução / Abstract: Heteroptera have peculiarities, including varying numbers of testicular lobes and different coloration of the peritoneal sheath between species. In addition to these features, some species in the Pentatomidae family have testicular lobes with morphologies and cells that are differentiated from the others, leading to the formation of spermatozoa with diversified functions. Although Heteroptera have many peculiar features, such as those previously reported, the study of their evolution requires detailed analysis. Thus, this study aimed to analyze the evolution of the characteristic number of lobes, peritoneal sheath pigmentation, production of non-fertilizing sperm and karyotype based on phylogenetic reconstructions using molecular markers, such as the COI, 16S and nuclear 18S mitochondrial genes. Thus, portions of genes from 25 Heteroptera species, including 12 from the Coreidae family and 13 from the Pentatomidae family, were sequenced. These genes alone did not provide reliable inference for evolutionary analyzes. With such concatenated genes, information could be added, but due to low consistency in the branches, the resulting evolutionary inferences must be viewed with caution. Thus, this research demonstrated the complexity of the distributions of the testicular and cytogenetic characteristics inferred by molecular phylogeny, and it is necessary to extend these studies with new approaches, such as the use of morphological or other molecular markers to elucidate evolution / Doutor
30

The life history of Orius tristicolor (White) in the laboratory

Abdellatif, Ahmed Hassan, 1935- January 1965 (has links)
No description available.

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