Note: page 74 is missing from archival and circulating copies / The present state af knowledge of the order Thysanaptera in Canada is reviewed. The aoder has been sorely neglected since Provenchar submitted a list af 35 eastern Canadian species in 1890. In contrast to the latest previaus estimate of 102 species (Heming, 1979), the number of species found in this study is 174 (143 described and 31 undescribed species). One new genus and five new species are reported as well as the European species Odontothrips biuncus which has been found for the first time in North America. Descriptions, illustrations and a dichatamaus key to the Canadian genera of the Thysanaptera ara given for the first time. Also included are lists of the species. hitherto found in Canada along with their localities•• and habitats•• In addition, an alternative computer-compatible key is presented for the suborder Tubullfera. The distribution and study af the order in Canada are discussed and notes on collection, classification, biology and economic importance are given. / Ce travail revise l’etat de nos cannais.ance. sur l’ordre de. Thysanopteres au Canada. Ce groupe a fait l’objet de peu d’etudes depuis la publication de Provencher (1890), qui enumerait 35 especes pour l’est du Canada. Dans la presente etude, nous rapportons . 174 especes (143 especes decrites, 31 especes non decrit••) alors qu’Heming (1979) n’en citait que 102 especes. pour ce pays. On y cree un nouveau genre et 5 nouvelles especes, en plus de recolter pour la premiere fois l’espece europeanne, Odonthrips biuncus en Amerique du Nord. L’auteur decrit et illustre pour la premiere fois. les. genres de Thvsanoptere. representes dans la fauna canadienne. De plus, on y trouve une liste des especes presentes au Canada, accompagnee de notes sur leur repartition geographique et leur habitat. On y inclut un tableau dichotomique conventionnel ainsi qu’un tableau de determination adape a l’ordinateur. pour Ie sous-ordre des Tubuliferes. Ce travail fournit egalemant, pour les Thysanopteres du Canada, une discussion sur leur repartition Geographique et des renseignements sur leur recolte et classification, leur biologie et importance economique.

Petri dish and olfactometer tests demonstrated that Goniozus natalensis (Gordh) females exhibit a host-searching response upon contact and at a short distance by olfaction, to a kairomone in the frass of its natural host Eldana saccharina (Walker). The host-searching response was found to be elicited by E. saccharina frass from a range of substrates, namely: two host plants of E. saccharina, papyrus and sugarcane, and four media: sugarcane, papyrus, and cellulose based media and a synthetic medium containing no plant material. The host-searching response was not elicited by Sesamia calamistis (Hamps) sugarcane medium frass. The sexual state and age of G. natalensis females were found to influence the host-searching behaviour. Mated females showed the behaviour in the petri dish bioassays only after completing their preoviposition time of two to three days, whilst virgin females took longer, even though their preoviposition time was found to be the same. The response to male or female produced E. saccharina sugarcane frass was not statistically different, nor was there a statistically significant preference for either frass type, given the choice. Four way olfactometer tests showed that an E. saccharina sugarcane frass odour elicited a host-searching behaviour in mated two to three day old G. natalensis females. Various solvents were tested for their ability to isolate the kairomone from E. saccharina sugarcane frass. Chloroform proved to be the best solvent when tested in petri dish and olfactometer bioassays. The preliminary results of the GC/MS analysis of the chloroform extract of E. saccharina sugarcane frass are presented. The chemicals identified are compared with chemicals identified as host location kairomones for other insect parasitoid-host studies. / Thesis (M.Sc.)-University of Natal, 1990.

Thesis (M. Sc.)--Carleton University, 2002. / Includes bibliographical references (p. 21-25). Also available in electronic format on the Internet.

Thesis (M.Sc.) - Carleton University, 2008. / Includes bibliographical references (p. 63-67). Also available in electronic format on the Internet.

Thesis (Ph. D.)--University of Washington, 1999. / Vita. Includes bibliographical references (leaves 96-112).

Thesis (Ph. D.)--University of Washington, 2004. / Vita. Includes bibliographical references (leaves 82-92).

The quest for patterns in community organisation is a daunting task which may be made easier by concentrating on communities associated with a restricted range of resources and therefore of relative simplicity. Here, the phytophagous insect community on the African fig tree Ficus burtt-davyi Hutch. was studied in an attempt to gain some insight into the factors which influence the composition of insect herbivore communities at a very local level, on individual plants of one host species at a single location. The tree's phenological patterns were detennined, due to their relevance to herbivores, particularly those which are host-specific feeders. The trees exhibited inter-tree asynchrony and intra-tree synchrony in fruit crop initiation, whereas leaf production was synchronous both within and between trees. Sixteen frequently occurring phytophagous insect species fed on the 123 F. burtt-davyi trees in the study area over a period of one year. Factors with the potential to influence the composition of this community were investigated at levels of the whole community (species richness), the guild, and the individual species. At each 'level' the effects of the measured factors on fluctuations in community composition were investigated, both over time (i.e. temporally) and spatially from tree to tree. During the year the phytophage community was influenced largely by temperature, although rainfall and tree phenological changes did exert varying influences on the abundances of guilds and individual species. Tree to tree variation in species richness (and thus commensurately, in the frequencies of occurrence of guilds and individual species) was influenced primarily by tree architectural complexity. Architecturally more complex trees hosted a greater number of species, a relationship largely attributable to effects of passive sampling and within-tree microhabitat heterogeneity and/or the availability of living space. The distributions of the leaf and stem piercing species were strongly associated with the presence of ants and this relationship manifested itself within the community as a whole. The degree of isolation of trees had consequences for individual species and for overall species richness, with the numbers of species present decreasing as trees became more isolated. A detailed analysis of guild distributional patterns revealed that the most important influential factors were those also evident at the level of the whole community and that species within guilds were, on the whole, no more similar to one another with respect to their habitat preferences than species from different guilds. The grouping of species into functional units therefore threw no additional light on the way in which this community is organised. An analysis of possible interspecific interactions between all of the phytophagous species in the community revealed only positive associations, both between species within guilds and between those in different guilds. These were doubtless attributable to autocorrelation as a result of similar habitat preferences. Competition was therefore rejected as an organising force within the community.

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

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