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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.
1

A systematic revision of the Cylindroleberididae (Crustacea: Ostracoda: Myodocopa)

Syme, Anna Unknown Date (has links) (PDF)
Ostracods of the family Cylindroleberididae are speciose, widespread, and well-defined by morphological features including the possession of gills. Despite the family having been divided into three subfamilies, five tribes, 32 genera, and more than 200 species, the relationships between its species have never been analysed phylogenetically. Twenty-five of the 32 genera are not defined by unique features but rather combinations of characters, and may therefore be historical constructions rather than evolutionary groups. The classification is of limited functional and predictive use, and requires a systematic revision. (For complete abstract open document)
2

The taxonomy, systematics and evolutionary biology of the Gyliauchenidae Fukui, 1929 (1918) (Platyhelminthes: Digenea)

Hall, K. Unknown Date (has links)
No description available.
3

The thelastomatoidea (nematoda: oxyurida) of Australian burrowing cockroaches (Blattodea: Geoscapheinae, Panesthiinae)

Jex, A. R. Unknown Date (has links)
No description available.
4

A revision of the Nearctic Species of Platycheirus Lepeletier and Serville (Diptera: Syrphidae)

Young, Andrew D. 09 May 2012 (has links)
The Nearctic members of the genus Platycheirus Lepeletier and Serville are revised. Five species, Platycheirus alpigenus Nielsen and Barkalov, Platycheirus brunnifrons Nielsen, Platycheirus clausseni Nielsen, Platycheirus speighti Doczkal, Stuke, and Goeldlin, and Platycheirus splendidus Rotheray, are newly recorded for the Nearctic Region, while three species, Platycheirus sp. trichopus, Platycheirus sp. “hyperboreus dark form” and Platycheirus n. sp. “perpallidus1” are new manuscript names. Females of 42 species are described for the first time. The genus Pyrophaena Schiner is resurrected. The genus Tuberculanostoma Fluke is synonymized with Platycheirus. An illustrated key to all 73 males and 52 females of Platycheirus and the males and females of the 3 species of Pyrophaena occurring in the Nearctic region is provided. Morphological and combined morphological/molecular COI phylogenetic analyses of the Platycheirus albimanus group are presented, as well as a molecular analysis of all available Platycheirus COI sequences. The species groups within Platycheirus are redefined based on these analyses. / NSERC-CANPOLIN
5

Systematics and biogeography of Australian wet tropics coelometopini (Coleoptera: Tenebrionidae: Coelometopinae)

Bouchard, P. Unknown Date (has links)
No description available.
6

Análise filogenética e morfológica da subfamília pangoniinae (Diptera: Tabanidae), com ênfase na tribo Scionini / Phylogenetic and morphological analysis of the subfamily Pangoniinae (Diptera: Tabanidae),with emphasis on the tribe Scionini

Carmo, Daniel Dias Dornelas do 27 March 2014 (has links)
Tabanidae (Diptera: Brachycera), a maior família da infraordem Tabanomorpha, possui aproximadamente 4500 espécies válidas, que se distribuem por todas as regiões biogeográficas, com exceção da Antártica. São insetos cujo tamanho varia de quatro a trinta mm. As fêmas são hematófagas, e os machos visitam flores. A classificação de Tabanidae constitui um problema histórico, e apesar de um número grande de autores ter abordado o problema, poucos são os trabalhos que trataram do grupo dentro de uma perspectiva filogenética. Nesse contexto, este trabalho, junto com Lessard et al. (2013 Molec.Phylog.Evol. 68: 516540), são os primeiros tratados envolvendo a classificação da Tribo Scionini (Tabanidae: Pangoniinae) utilizando análises filogenéticas. Para o presente estudo, foram levantados caracteres da cabeça, asa e terminálias feminina e masculina dos espécimes analisados e esses caracteres foram compilados em uma matriz de 37 táxons por 44 caracteres. A matriz foi analisada com o auxílio do programa TNT. Desta análise foram obtidos quatro cladogramas igualmente parcimoniosos, sobre os quais foi utilizado o consenso estrito. No cladograma de consenso, duas subfamílias de Tabanidae são mostradas como grupos naturais (Tabaninae e Chrysopsinae), enquanto a monofilia de Pangoniinae permaneceu não resolvida na análise com pesos iguais. Quando utilizada pesagem implícita, todas as três famílias são mostradas como monofiléticas. Os Scionini se mostraram um grupo merofilético, assim como dois de seus gêneros, Scaptia e Fidena. A partir dos resultados aqui obtidos, é indicada a necessidade para a reformulação futura da delimitação dos Scionini, bem como é apontada a necessidade de revisão de alguns gêneros que compõem a subfamília Pangoniinae. / Tabanidae (Diptera: Brachycera), the most speciose family within the infraorder Tabanomorpha, comprises approximately 4500 valid species, distributed through all the biogeographical regions, except Antarctica. These insects range in length from four to tirty millimeters. Females are hematophagus and males visit flowers. The classification of Tabanidae constitutes an historical problem and, despite the fact that a great number of authors had addressed the problem, few are the works that treated the group from a phylogenetic perspective. In this context, this work, together with Lessard et al. (2013 Molec.Phylog.Evol. 68:526-540), are the first treatises dealing with the classification of the tribe Scionini (Tabanidae: Pangoniinae) based on a phylogenetic analysis. In the present work, characters from head, wing and both female and male terminalia were coded into a matrix of 37 taxa by 44 characters. The matrix was analyzed with the software TNT. From this analysis four equally parsimonious cladograms were obtained, over which the strict consensus was calculated. In the consensus cladogram, two subfamilies of Tabanidae are shown as natural groups (Tabaninae and Chrysopsinae), whereas the monophyly of Pangoniinae was not recovered with equal weights parsimony. When implied weighting was used however, all the three subfamilies are shown to be monophyletic groups. The Scionini were shown as merophyletic, as did two of its genera, Scaptia and Fidena. From the results herein obtained, it is indicated the need for the re-delimitation of Scionini. It is also argued that revisions of some genera comprised within Pangoniinae are urgent for achievement of improved taxonomic stability in this subfamily.
7

A spore atlas of New Zealand ferns and fern allies

Large, M. F. January 1989 (has links)
Whole document restricted, see Access Instructions file below for details of how to access the print copy. / This work constitutes a detailed study of the spores, of the ferns and fern allies, both native and adventive, which grow in New Zealand, from the Kermadec Islands in the North, to the Chatham Islands in the East and the Subantarctic Islands in the South. Twenty live families with sixty five genera, two hundred and eleven species (of which c.20 are introduced) and three subspecies are included. Seven species are heterosporous the remainder are homosporous. Trilete spores are found in c.104 species representing c.30 genera. Perine is present in most taxa (with the exception of Gleichenia) and ranges from the large and sac-like form as seen in Cyathea smithii, to the thin and reduced form seen in Adiantum. Monolete spores are found in c.109 species representing c.37 genera (two genera are included twice, Isoetes which has trilete megaspores and monolete microspores and Lindsaea which has both monolete and trilete species). Perine is present in most taxa (except Sticherus spp.) and ranges from a fine deposit as seen in the Psilotaceae, to an enlarged form, heavily winged, as seen in the Aspleniaceae. Sculpture in all taxa (with the exception of the Lycopodiaceae and some members of the Ophioglossaceae, which may have ornamentation distributed distally), is present on both distal and proximal faces. One adventive taxon Equisetum arvense L. has an unusual circular laesura and elaborate elaters. Light micrographs of acetolysed and fresh spores along with scanning electron micrographs, are included for each taxon. Keys presented, are based on gross spore morphology and are applicable to fresh and acetolysed material. Descriptions include a list of synonymous species, details of spore shape, laesura/ae details, perine/exine sculpture and thickness (where sections allow), size (measured from n=50 spores per population), for samples treated with cotton blue (lactophenol aniline blue formula), mounted in glycerine jelly and acetolysed samples, mounted in silicone oil. Percentage size differences for acetolysed material mounted in glycerine jelly are also noted, along with previous spore dimensions recorded in the literature. Descriptions also contain chromosome number, where known, a list of previously recorded descriptions, a brief indication of geographic location and a list of vouchers for each sample. Experiments on the size and morphology of fern spores in reaction to different preparation techniques are discussed. Fresh spores of seven species, four trilete (Adiantum fulvum, Cyathea smithii, Hymenophyllum flabellatum and Lycopodium volubile) and three monolete (Blechnum chambersii, Paesia scaberula and Tmesipteris elongata), were assessed wth regard to the effect of three standard pretreatments (lactophenol aniline blue, 10% KOH, acetolysis) and two mounting media (glycerine jelly and silicone oil). Changes in morphology and size of the various wall layers were noted in comparison to spores observed fresh in water. Results indicate that variation includes shrinkage e.g. silicone oil and expansion of both exine and perine in glycerine jelly. Both effects are modified by previous treatments.
8

Mountain beech forest on Mount Ruapehu: dynamics, disturbance, and dieback

Steel, Marion Gaynor January 1989 (has links)
The role of, and response to, disturbance, in the dynamics of the mountain beech forest at western Mt Ruapehu, was examined, using palynology, dendrochronology, and vegetation survey. The pollen record indicates that, two thousand years ago, the west Ruapehu forest was dominated by Nothofagus solandri. About 1800 years B.P., the eruption of Lake Taupo devastated the forest. Though Halocarpus spp. and Phyllocladus asplenifolius were important early colonizers, Nothofagus solandri re-established itself close to its present limits after the eruption. Fire, from about 650 years ago onwards, did not affect the beech forest, but did affect the coniferous vegetation on the ring plain near the mountain. The age structure of the forest shows that there was a large disturbance event shortly before 1740. A dieback occurring about 1969 appears to have been the largest episode of mortality since 1740, larger than the dieback episode described by Cockayne at the beginning of this century. Dieback occurred as a short peak-period of Nothofagus solandri death about 1969. It was the large trees of the mature cohort which tended to be killed by dieback rather than the smaller individuals. Tree-ring analysis, showed that narrow tree-rings occurred in beech in the 1960's. Extreme rainfall years in the early 1960's may have put the beech trees under stress, making them susceptible to dieback. The drought in 1969 may have precipitated extensive mortality. The characteristics of N. solandri rings from Ruapehu are similar to ring characteristics of that species from South Island studies. The 1982 cyclone had a noticeable impact on the forest, affecting some areas severely. However, the impact was relatively minor compared to the influence of dieback. The mean density of trees >= 10cm dbh was 520 stems/ha., of which 220 stems/ha. were Nothofagus solandri. The mean basal area was 22m2 /ha., of which 11m2 /ha. was N. solandri. The basal area is very low compared to that in other N.Z. forests. N. solandri, Griselinia littoralis, Phyllocladus asplenifolius, Podocarpus hallii, and Libocedrus bidwillii, made up 35, 22, 16, 9, and 8 percent, respectively, of the total density. Basal area, density, and species composition varied as much within sites, as between them. The shrub layer formed a large part of the vegetation at west Ruapehu. Coprosma species were particularly abundant. There is sufficient regeneration to indicate that a new cohort of N. solandri is becoming established in most areas. Some areas will probably remain in shrubland for many decades. The result of dieback and windthrow has been to virtually eliminate the canopy of large old beech trees, and to increase the heterogeneity of stand structure. N. solandri seedling densities are not as high as those found in many South Island beech forests. Nothofagus solandri is growing faster than are most of the co-existing tree species, and it appears likely that it will continue as the dominant tree species. Implications for forest management are discussed.
9

A spore atlas of New Zealand ferns and fern allies

Large, M. F. January 1989 (has links)
Whole document restricted, see Access Instructions file below for details of how to access the print copy. / This work constitutes a detailed study of the spores, of the ferns and fern allies, both native and adventive, which grow in New Zealand, from the Kermadec Islands in the North, to the Chatham Islands in the East and the Subantarctic Islands in the South. Twenty live families with sixty five genera, two hundred and eleven species (of which c.20 are introduced) and three subspecies are included. Seven species are heterosporous the remainder are homosporous. Trilete spores are found in c.104 species representing c.30 genera. Perine is present in most taxa (with the exception of Gleichenia) and ranges from the large and sac-like form as seen in Cyathea smithii, to the thin and reduced form seen in Adiantum. Monolete spores are found in c.109 species representing c.37 genera (two genera are included twice, Isoetes which has trilete megaspores and monolete microspores and Lindsaea which has both monolete and trilete species). Perine is present in most taxa (except Sticherus spp.) and ranges from a fine deposit as seen in the Psilotaceae, to an enlarged form, heavily winged, as seen in the Aspleniaceae. Sculpture in all taxa (with the exception of the Lycopodiaceae and some members of the Ophioglossaceae, which may have ornamentation distributed distally), is present on both distal and proximal faces. One adventive taxon Equisetum arvense L. has an unusual circular laesura and elaborate elaters. Light micrographs of acetolysed and fresh spores along with scanning electron micrographs, are included for each taxon. Keys presented, are based on gross spore morphology and are applicable to fresh and acetolysed material. Descriptions include a list of synonymous species, details of spore shape, laesura/ae details, perine/exine sculpture and thickness (where sections allow), size (measured from n=50 spores per population), for samples treated with cotton blue (lactophenol aniline blue formula), mounted in glycerine jelly and acetolysed samples, mounted in silicone oil. Percentage size differences for acetolysed material mounted in glycerine jelly are also noted, along with previous spore dimensions recorded in the literature. Descriptions also contain chromosome number, where known, a list of previously recorded descriptions, a brief indication of geographic location and a list of vouchers for each sample. Experiments on the size and morphology of fern spores in reaction to different preparation techniques are discussed. Fresh spores of seven species, four trilete (Adiantum fulvum, Cyathea smithii, Hymenophyllum flabellatum and Lycopodium volubile) and three monolete (Blechnum chambersii, Paesia scaberula and Tmesipteris elongata), were assessed wth regard to the effect of three standard pretreatments (lactophenol aniline blue, 10% KOH, acetolysis) and two mounting media (glycerine jelly and silicone oil). Changes in morphology and size of the various wall layers were noted in comparison to spores observed fresh in water. Results indicate that variation includes shrinkage e.g. silicone oil and expansion of both exine and perine in glycerine jelly. Both effects are modified by previous treatments.
10

Mountain beech forest on Mount Ruapehu: dynamics, disturbance, and dieback

Steel, Marion Gaynor January 1989 (has links)
The role of, and response to, disturbance, in the dynamics of the mountain beech forest at western Mt Ruapehu, was examined, using palynology, dendrochronology, and vegetation survey. The pollen record indicates that, two thousand years ago, the west Ruapehu forest was dominated by Nothofagus solandri. About 1800 years B.P., the eruption of Lake Taupo devastated the forest. Though Halocarpus spp. and Phyllocladus asplenifolius were important early colonizers, Nothofagus solandri re-established itself close to its present limits after the eruption. Fire, from about 650 years ago onwards, did not affect the beech forest, but did affect the coniferous vegetation on the ring plain near the mountain. The age structure of the forest shows that there was a large disturbance event shortly before 1740. A dieback occurring about 1969 appears to have been the largest episode of mortality since 1740, larger than the dieback episode described by Cockayne at the beginning of this century. Dieback occurred as a short peak-period of Nothofagus solandri death about 1969. It was the large trees of the mature cohort which tended to be killed by dieback rather than the smaller individuals. Tree-ring analysis, showed that narrow tree-rings occurred in beech in the 1960's. Extreme rainfall years in the early 1960's may have put the beech trees under stress, making them susceptible to dieback. The drought in 1969 may have precipitated extensive mortality. The characteristics of N. solandri rings from Ruapehu are similar to ring characteristics of that species from South Island studies. The 1982 cyclone had a noticeable impact on the forest, affecting some areas severely. However, the impact was relatively minor compared to the influence of dieback. The mean density of trees >= 10cm dbh was 520 stems/ha., of which 220 stems/ha. were Nothofagus solandri. The mean basal area was 22m2 /ha., of which 11m2 /ha. was N. solandri. The basal area is very low compared to that in other N.Z. forests. N. solandri, Griselinia littoralis, Phyllocladus asplenifolius, Podocarpus hallii, and Libocedrus bidwillii, made up 35, 22, 16, 9, and 8 percent, respectively, of the total density. Basal area, density, and species composition varied as much within sites, as between them. The shrub layer formed a large part of the vegetation at west Ruapehu. Coprosma species were particularly abundant. There is sufficient regeneration to indicate that a new cohort of N. solandri is becoming established in most areas. Some areas will probably remain in shrubland for many decades. The result of dieback and windthrow has been to virtually eliminate the canopy of large old beech trees, and to increase the heterogeneity of stand structure. N. solandri seedling densities are not as high as those found in many South Island beech forests. Nothofagus solandri is growing faster than are most of the co-existing tree species, and it appears likely that it will continue as the dominant tree species. Implications for forest management are discussed.

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