Over the last 50 years populations of certain farmland birds have undergone severe declines over the same timescale that agriculture has intensified. The larvae of grassland sawflies (Hymenoptera, Symphyta) are a key component of the fledgling diet and it is thought that agri-intensification has reduced the numbers of these insects to such an extent that the populations of bird species dependent on them are limited. Sawfly populations may be more than usually susceptible to disturbance because firstly, their adult stages are poor dispersers and secondly, some species possess Complementary Sex Determination (CSD), a mechanism which can produce sterile males under inbreeding conditions. This study has produced a sawfly transcriptomic library through the use of 454 pyrosequencing, the first genetic resource for any farmland sawfly. From this library, a set of 13 polymorphic microsatellite markers were isolated for use in the common farmland sawfly Dolerus aeneus. Using these markers, three Scottish populations of D. aeneus, a species common to all six UK sites sampled in this study, exhibited similar levels of genetic diversity and low levels of genetic differentiation. However, evidence of inbreeding was detected in each of the three populations. In addition, potential diploid males were detected in D. aeneus using microsatellite markers, a primary indication that CSD may be operating in this species. The population genetic analysis in the current study suggests that fragmentation of suitable sawfly habitat as a result of agricultural intensification has not yet acted to isolate D. aeneus populations, although some genetic effects (inbreeding and low diversity compared with non-threatened hymenopterans) are apparent. In addition, diploid males have been detected which may have compromised fertility. This study will be of interest to research groups working on the genetics of the Hymenoptera and on the conservation and management of sawflies and the bird species dependent on them.

Tez (Yüksek Lisans) - Süleyman Demirel Üniversitesi, Fen Bilimleri Enstitüsü, Biyoloji Anabilim Dalı, 2008. / Kaynakça var.

Callandrena, a subgenus of 80 described species of bees in the genus Andrena (Hymenoptera: Andrenidae) is shown, via phylogenetic analysis of both mitochondrial and nuclear DNA sequence data, to be polyphyletic. The characters previously uniting this group have likely arisen by convergent evolution among unrelated lineages that have independently specialized on flowers of the Asteraceae for pollen consumption. At this time, we cannot definitively state whether there are two or three clades of bees formerly ascribed to Callandrena, nor whether one clade may belong to the European subgenus Chrysandrena as has been proposed, so we do not erect a new subgenus of Andrena at this time. The limits of Callandrena sensu stricto are provisionally delimited based on a single morphological character. The phylogenetic relationships of the two groups relative to other Andrena subgenera are discussed in Chapter 2. In Chapter 3, Clade B, as defined for Callandrena in Chapter 2, is used to investigate the evolution of pollen host choice. Diet breadth is determined by analysis of pollen loads of at least 20 individual females per species. The choice of host and degree of specificity are then mapped onto the molecular phylogeny to investigate the evolution of these traits. Oligolecty appears to be the ancestral state in Andrena; polylecty has evolved several times; and reversals to oligolecty within these lineages have also occurred. Within the oligolectic lineage studied, host shifts were not uncommon. During the course of this study, a number of undescribed species were collected. Five are described in Chapter 4. / text

No description available.

Mimesa is a Holarctic genus of predatory sphecoid wasps of which 36 species are found in America. The present study is a revision of the American fauna presenting keys to species, standardized descriptions, distribution maps and biological information for each species. / Fourteen species are here described as new: M. cahuilla, M. cheyenne, M. chiricahua, M. gabrieleno, M. ipai, M. jicarilla, M. klamath, M. miwoka, M. nisenan, M. senijextee, M. serrano, M. tequila, M. tolteca and M. zapoteca. In addition one subspecies, M. gregaria simplex, has been raised to species rank and 7 previously recognized species have been synonymized as follows: M. polita with M. dawsoni, M. atriventris with M. cressonii, M. iroquois with M. ezra, M. impressifrons with M. edentata and M. basirufa, M. nebrascensis and M. mallochi with M. lutaria. A lectotype has been designated for M. mexicana. / A total of 365 illustrations are presented to supplement keys and descriptions.

The following morphological structures of the ovipositor of Homolobus truncator (Say) (Hymenoptera : Braconidae) are described and hypotheses of their functions are proposed: a series of sharp ridges on the distal surface of the notch helps maintain a grip on the inner surface of the host cuticle; the sperone directs eggs away from the inner surface of the ventral valves; a flap-like structure on each ventral valve covers the portal through which eggs pass; the valvillus maintains position of the egg within the ovipositor and acts against the egg to force it out; ctenidia on the inner surface of the ventral valves move eggs along the basal half of the egg canal; recurved barbs at the apex of each ventral valve hook into the inner surface of the host cuticle to maintain purchase while the thick dorsal valve is inserted into the host. The tribe Maxfischeriini (Hymenoptera : Braconidae) is emended to subfamily status based on morphological and biological evidence. A novel egg morphology is described for Maxfischeria, representing a new life history strategy among Braconidae. Based on egg and ovipositor morphology, I suggest that Maxfischeria is a proovigenic, koinobiont ectoparasitoid. Five new species of Maxfischeria are described (M. ameliae sp. nov., M. anic sp. nov. M. briggsi sp. nov., M. folkertsorum sp. nov., and M. ovumancora sp. nov.). A phylogenetic analysis of morphological and molecular characters for the braconid subfamily Euphorinae is presented. The results imply a revised classification that recognizes 9 tribes and 44 genera. Proposed changes include: Meteorus and Zele are recognized as Meteorinae. Planitorus and Mannokeraia are included among Euphorinae and comprise the tribe Planitorini. Cosmophorini, Euphorini, Helorimorphini, Perilitini, Leiophron, and Perilitus are redefined. The following synonyms are proposed: Cryptoxilonini and Dinocampini with Cosmophorini; Myiocephalini and Proclithrophorini with Perilitini; Myiocephalus with Microctonus; Bracteodes, Falcosyntretus, Sculptosyntretus, Syntretellus, Syntretomorpha, and Syntretoriana with Syntretus and are recognized as subgenera; Perilitus (Townesilitus) with Microctonus and are recognized as a subgenus. Transitions in host associations are examined with ancestral state reconstruction. Some ambiguous nodes in the reconstruction are reconciled by examining the overlap in host associations.

Thesis (Ph. D.)--University of California, Riverside, 2009. / Includes abstract. Includes bibliographical references. Issued in print and online. Available via ProQuest Digital Dissertations.

Thesis (m.s.)--University of Kentucky, 2004. / Title from document title page (viewed Jan. 7, 2005). Document formatted into pages; contains xiv, 475p. : ill. Includes abstract and vita. Includes bibliographical references (p. 469-473).

Made available in DSpace on 2014-06-11T19:28:37Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-08-06Bitstream added on 2014-06-13T20:18:26Z : No. of bitstreams: 1 000754567.pdf: 1086219 bytes, checksum: baa5c2971d53e757d0b998e75e6cd03c (MD5) / As formigas cortadeiras, insetos pertencentes aos gêneros Atta e Acromyrmex (Hymenoptera: Formicidae), recebem no Brasil, os nomes populares de saúvas e quenquéns. Devido a seu hábito alimentar polífago ocupam diversos ambientes, acarretando danos econômicos em áreas cultivadas. As partes vegetais cortadas são transportadas para suas colônias e preparadas para servir de substrato ao fungo simbionte do qual se alimentam. Apesar de inúmeros estudos sobre esses insetos sociais, novas descobertas sobre o comportamento das formigas, seus atos ou estratégias comportamentais que levam esses organismos a encontrar e utilizar as fontes de energia e nutrientes para a sua sobrevivência são regularmente divulgadas na literatura, evidenciando uma grande diversidade dos seus padrões de organização social. Dessa maneira, o presente trabalho foi realizado com o objetivo de avaliar a percepção de odores de diferentes substratos por Atta sexdens rubropilosa Forel, 1908 (Hymenoptera: Formicidae) através de catálogos comportamentais. Os experimentos foram conduzidos no Laboratório de Insetos Sociais – Praga, pertencente ao Departamento de Proteção Vegetal - Faculdade de Ciências Agronômicas – Universidade Estadual Paulista (UNESP) – Campus de Botucatu, SP. O estudo foi dividido em três capítulos. No primeiro capítulo foram desenvolvidos estudos de percepção de odores através da utilização de olfatômetro, bem como estudo do comportamento das formigas cortadeiras submetida a voláteis atrativos através da elaboração de catálogo comportamental. No segundo capítulo estudos de percepção de voláteis repelentes e elaboração de catálogo comportamental. No terceiro capítulo foram realizados estudos para determinar a distância em que as formigas cortadeiras percebem a fonte de odor. Os principais resultados demonstraram que as formigas cortadeiras na percepção de voláteis,... / The leaf-cutting ants, insects belonging to the gems Atta and Acromyrmex genre (Hymenoptera: Formicidae), are called in Brazil “saúvas” and “quenquéns”. Due to their polyphagous food habit they occupy several environments, resulting in economic damage to cultivated areas. The plant parts that are cut and transported to their colonies and prepared to serve as a substract for the symbiotic fungus from which they feed. In spite of the númerous studying about these social insects, new discoveries about the ants´ behavior, their acts or behavioral strategies that lead these organisms to find and use the energy resources and nutrients for their survival are regularly disclosed in literature, showing a great variety in their social organization patterns. This way, the present study was performed having as its goal to evaluate the smelling perception of different substracts in Atta sexdens rubropilosa Forel, 1908 (Hymenoptera: Formicidae) through behavioral catalogues. The experiments were conducted in the Social pest Insects Lab, belonging to the Plant protection Department – Agronomic Science University – Universidade Estadual Paulista (UNESP). The sturdy was divided in three chapters. In the first chapter studies of smelling perception were developed using a olfactometer, as well as the study of leaf-cutting ants exposed to volatile attractive by developing behavioral catalog. In the second chapter, studies of volatile repellents and preparation of a behavioral catalog. In the third chapter studies were carried out to determine the distance in which the leaf-cutting ants notice the smell source. The main results showed that leaf-cutting ants notice the volatile ones, either attractive ones or the repellent ones, showing different behavior in relation to the offered material. The results obtained demonstrated that the third chapter ants realize the volatile attractive distances of ...

The host-searching behaviour of the parasitoid Coccophagus atratus Compere was investigated. C. atratus parasitoids have unusual host relationships. Female offspring develop in scale insects but male offspring develop hyperparasitically on their conspecific females, or on other parasitoid species. C. atratus females, therefore, must locate, identify and oviposit into two different types of hosts. A primary aim of this thesis, was to identify when and how the behaviour of a female, searching for hosts suitable for female offspring, differed from that of a female searching for hosts suitable for male offspring. This was done by investigating and comparing the behaviour of virgin and mated females. Virgin females can lay only male eggs while mated females can lay both male and female eggs. The role of plant odours and host odours in attracting C. atratus females to the host habitat and to their scale insect hosts was examined with the aid of an olfactometer. Field observations, to test the validity of results obtained in laboratory experiments, indicated that C. atratus females do not search initially for for their hosts' food plants, but search directly for hosts. Only when hosts were physically located did the behaviour of virgin and mated females differ. Recognition cues used by the females to distinguish between the two types of hosts were identified. Finally, the implications of results obtained were discussed in relation to ecological and evolutionary aspects of heteronomous parasitoid biology.