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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.
11

A REVISION OF THE NEW WORLD AND SELECT OLD WORLD SPECIES OF CREMNOPS FÖRSTER (HYMENOPTERA: BRACONIDAE: AGATHIDINAE)

Tucker, Erika M. 01 January 2015 (has links)
Parasitoid wasps are an important group of organisms in need of systematic revision. This dissertation examines the cosmopolitan parasitoid wasp genus Cremnops. It is a compilation of three projects and significantly advances the taxonomic foundation of the genus. The New World species of the genus Cremnops are revised. Thirty-three species of Cremnops are treated; five are described as new, i.e., C. bertae sp. nov., C. cluttsis sp. nov., C. nymphius sp. nov., C. wileycoyotius sp. nov. and C. witkopegasus sp. nov. Six species are synonymized, i.e., Cremnops caribensis Berta 1998, is synonymized under C. guanicanus Wolcott 1924; C. nigrosternum (Morrison 1917) is synonymized under C. haematodes (Brullé 1846); C. punctatus Berta 1998, is synonymized under C. marshi Berta 1998; C. sharkei Berta 1998, is synonymized under C. montrealensis (Morrison 1917); C. turrialbae Berta de Fernandez 1998, is synonymized under C. ferrugineus (Cameron 1887); and C. misionensis Berta 1987, is synonymized under C. slossonae (Morrison 1917). Cremnops florissanticola is transferred to its original combination Bracon florissanticola Cockerell 1919, st. rev. The species concept Cremnops desertor and its complicated taxonomic history are discussed. A phylogenetic distance tree, based on COI data, is used to help delimit species. The recognition of C. alterans Enderlein and C. malayensis Bhat is proposed. I propose new combinations for five African species that are currently placed in Cremnops, i.e., C. atripennis Szépligeti 1914 and C. elegantissima Szépligeti 1908 are moved to Disophrys; C. borealis (Szépligeti 1914) and C. rubrigaster Masi 1944 are moved to Biroia; and C. pulchripennis Szépligeti 1905 is moved to and renamed Biroia neopulchipennis. These changes result in Disophrys atripennis (Szépligeti 1915) becoming a junior homonym, which is changed to Disophrys szatripennis. Additionally, two species are proposed as nomen dubia: C. rufitarsis Szépligeti 1913 and C. schubotzi Szépligeti 1915. Included are a molecular phylogeny, a dichotomous key, links to distribution maps, an electronic interactive key, images of holotypes, and suggestions for further research.
12

Gastrotricha of Sweden - Biodiversity and Phylogeny

Kånneby, Tobias January 2011 (has links)
Gastrotricha are small aquatic invertebrates with approximately 770 known species. The group has a cosmopolitan distribution and is currently classified into two orders, Chaetonotida and Macrodasyida. The gastrotrich fauna of Sweden is poorly known: a couple of years ago only 29 species had been reported. In Paper I, III, and IV, 5 freshwater species new to science are described. In total 56 species have been recorded for the first time in Sweden during the course of this thesis. Common species with a cosmopolitan distribution, e. g. Chaetonotus hystrix and Lepidodermella squamata, as well as rarer species, e. g. Haltidytes crassus, Ichthydium diacanthum and Stylochaeta scirtetica, are reported. In Paper II molecular data is used to infer phylogenetic relationships within the morphologically very diverse marine family Thaumastodermatidae (Macrodasyida). Results give high support for monophyly of Thaumastodermatidae and also the subfamilies Diplodasyinae and Thaumastodermatinae. In Paper III the hypothesis of cryptic speciation is tested in widely distributed freshwater gastrotrichs. Heterolepidoderma ocellatum f. sphagnophilum is raised to species under the name H. acidophilum n. sp. The results indicate that L. squamata may be a complex of at least two species. In Paper III and V the phylogeny of Chaetonotidae (Chaetonotida), the largest family within Gastrotricha, is inferred. The group suffers from a troubled taxonomy and is hypothesized to be nonmonophyletic. Results show that members of Dasydytidae are nested within the group. Since only 3 of 17 sampled genera are monophyletic, it is hypothesized that the cuticular structures used in current classification do not reflect phylogenetic relationships. The phylogenetic hypothesis generated in Paper V indicates a marine origin of the predominantly limnic Chaetonotidae with a subsequent secondary invasion to marine environments of some taxa. / Gastrotricha of Sweden - Biodiversity and Phylogeny
13

When Ground Beetles Fly: A Taxonomic Review of the Arboreal, Myrmecophilous Neotropical Genus, Homopterus (Coleoptera: Carabidae: Paussinae) with a new Species Description, Species Diagnoses, and Insights into Species Distributions

Hoover, Angela Marie, Hoover, Angela Marie January 2016 (has links)
A review of the species groups of the Neotropical myrmecophilous genus Homopterus Westwood is presented based on the first molecular phylogenetic analysis of the genus and morphological study of 260 specimens. Two new species groups, the H. subcordatus group and the H. filiko group are erected based on the results of the molecular phylogenetic analysis and morphological analysis. The genus consists of one species known only from Dominican amber, H. hispanolienses Nagel, and thirteen extant species, one of which is described as new: Homopterus filiko n.sp. from Peru. An illustrated dichotomous identification key to species, diagnoses of the species groups and updated distribution maps are provided. The potential of several of the species groups to harbor additional cryptic diversity is discussed.
14

Taxonomy and Phylogenetics of Island Damselflies (Odonata: Coenagrionidae: Vanuatubasis)

Saxton, Natalie Anne 16 June 2021 (has links)
Odonata is an order of charismatic insects, commonly called dragonflies and damselflies, that provide a rewarding study system to answer questions such as those related to diversity and biogeography. Despite being relatively well-studied compared to other insect orders, odonates have suffered from inconsistencies and disagreements about proper morphological terminology that provide barriers to incoming workers. These disagreements have subsequently led to confusion and the incorrect application of terms. Here, we clarify the terminology and propose standard terminology for terminal appendages. This terminology is employed in a taxonomic revision of Vanuatubasis Ober & Staniczek, 2009. This endemic genus of damselfly found on the island archipelago of Vanuatu and was previously only known from three species. Here, we formally describe and treat all known species of Vanuatubasis including the association of females for known species. We also describe new species Vantuatubasis evelynae sp. nov., V. insularivorum sp. nov., V. kapularum sp. nov., V. nunggoli sp. nov., V. punicea sp. nov., and V. xanthochroa sp. nov. from material collected in Vanuatu. An illustrated key to both males and females of all species within Vanuatubasis is provided as well as distributions for all known species. Finally, we explore the biogeographical patterns in Vanuatu using this genus. We reconstruct a phylogeny of Vanuatubasis, in the context of its two sister genera, to begin unraveling the complex biogeography of this lineage. We test hypothesis of dispersal from Fiji, routes of colonization across the archipelago, and how relationships reflect geographic proximity in the genus. The results provide a vital first step in understanding the faunistic patterns within Vanuatu, as well as broader patterns across the Pacific.
15

The Biogeography and Nesting Biology of Anthophora, with a Revision and Phylogeny of the Anthophora (Micranthophora)

Orr, Michael C 01 December 2017 (has links)
Bees are necessary pollinators for a vast array of different plants, including many which we rely on for food. In order to grow sufficient crops to feed the world’s growing population, we need to make sure our crops are visited by the most effective possible pollinators. However, this is complicated by the fact that there are over 4,000 bee species in North America, many of which vary in their pollination effectiveness and are difficult to identify. My dissertation’s first two data chapters focus on classifying the species of the xeric solitary bee group Anthophora subgenus Micranthophora, including seven newly described species, while also providing identification resources for telling them apart. With this group’s classification fixed, my third chapter then uses differences in the DNA of these species to reconstruct evolutionary trees of their relationships; those with more similar DNA sequences are grouped more closely together. I then use powerful modern methods to and determine how quickly new species have arisen throughout the entirety of the group’s evolutionary history, in order to determine how desertification has influenced the evolution of these xeric bees. My results suggest that the Neogene Uplift, a mountain-building event, initially increases their diversification rates, but climatic cooling and niche competition later greatly decrease these rates. Finally, my last chapter looks at bee evolution from a contemporary perspective, viewed through the lens of a new species of bee that actually excavates its nests in sandstone, Anthophora pueblo, despite the obvious time and energy costs of this behavior. In addition to describing this fascinating new species, I also use interdisciplinary methods from biology and geology to demonstrate that, although they prefer to use weaker sandstone, intermediate levels of sandstone hardness are likely beneficial to them, enabling future generations of their relatives to reuse nest tunnels for many years without excavating. Preliminary evidence also suggests that these bees benefit from protections afforded to them against parasites and pathogens that can destroy their nests and kill their offspring. Overall, this species will provide a terrific system for future studies of bee evolution and life history trade-offs. By performing these studies, my dissertation will enable a wealth of additional studies on these poorly known solitary bees.
16

A Revision Of The New World Species Of Donacaula Meyrick And A Phylogenetic Analysis Of Related Schoenobiinae (Lepidoptera: Crambidae)

Martinez Calez, Edda Lis 10 December 2010 (has links)
Phylogenetic relationships of 13 genera of Schoenobiinae (Lepidoptera: Crambidae) are postulated based on traditional characters of genitalia and wing venation and new characters of the descaled whole body. The phylogenetic analysis yielded one most-parsimonius tree (length 287 steps, CI= .36, RI= .62) that resulted in a monophyletic clade of all genera of Schoenobiinae examined. The monophyly of the Schoenobiinae is supported by a Bremer support value of five. Donacaula is not congeneric with the type-species of Schoenobius, S. gigantellus. The analysis confirms Lewvanich‘s hypothesis that Scirpophaga, Donacaula, Schoenobius, Catagela, and Helonastes are closely related. Based on this analysis, the New World genera appear to have originated in the Neotropical region with four independent dispersals to the Nearctic Region. The revision of Donacala resulted in recognition of 20 species that were previously described and descriptions of ten new species. Neotypes were designated for D. sordidella, D. unipunctella, D. tripunctella, D. dispersella, D. aquilella. Lectoypes were designated for D. albicostella, D. pallulella, D. immanis, D. pulverealis. Donacaula bicolorella was synonymized with D. roscidella, D. uniformella with D. albicostella, D. lanceolella with D. immanis, and D. amblyptepennis with D. longirostrella. Adults, wing venation, and genitalia of New World species of Donacaula are illustrated for the first time, and new distributional records are reported. A key to species, diagnoses, and photographs of imagoes and male and female genitalia are provided.
17

Diversity, systematics and phylogeny of dotillid crabs (Crustacea: Brachyura: Ocypodoidea: Dotillidae) in the Indonesian Archipelago / インドネシア列島における コメツキガニ科のカニ類 (甲殻亜門: 短尾亜目: スナガニ上科) の多様性とその系統分類学的研究

Murniati, Dewi Citra 25 September 2023 (has links)
京都大学 / 新制・課程博士 / 博士(理学) / 甲第24874号 / 理博第4984号 / 新制||理||1711(附属図書館) / 京都大学大学院理学研究科生物科学専攻 / (主査)教授 朝倉 彰, 教授 森 哲, 准教授 下村 通誉 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM
18

A Systematic Revision of the <i>Viola pedatifida>/i> Group and Evidence for the Recognition of <i>Viola virginiana</i>, a New Narrow Endemic of the Virginia Shale Barrens

Zumwalde, Bethany A. 17 September 2015 (has links)
No description available.
19

Paleontology and Sedimentology of the Alum Shale Formation at Björnberget, Västerbotten County, Sweden

Alexander, Mannelqvist January 2016 (has links)
A new locality of the Alum Shale Formation at Björnberget, Västerbotten County, of the lower allochthon of the Caledonian front is described herein. Two new species of acrotretid brachiopods were found. Tingitanella vilhelminia n. sp. adds another species to the monospecific genus. T. vilhelminia also extend the genus distribution to Sweden. Anabolotreta furcatus n. sp. is the first member of the genus found in Sweden and extend the stratigraphic range to Stage 5 of Cambrian Series 3. It also exhibits an unusual bifurcating shell structure described for the first time herein. One trilobite was found at the locality, Acadoparadoxides torelli, indicating that the exposures at Björnberget belong to the upper Acadoparadoxides (Baltoparadoxides) oelandicus superzone. The fauna found is impoverished in comparison to the fauna that has been described from Jämtland and reflects the depositional environment on the deep outer shelf with low sediment input. The known exposure at Granberget, close to Björnberget, is described with respect to the paleontology and sedimentology of the section. The fauna at Granberget could be extended with two new species of agnostids, Hypagnostus lingula and Hypagnostus mammillatus, to a total of six taxa of trilobites. The depositional environment was periodically affected by storms, depositing limestone layers composed of skeletal material. The Alum shale does not exhibit these sedimentary structures and have probably lost the majority of the them during diagenesis. / En hitintills obeskriven lokal av Alunskifferformationen vid Björnberget, Västerbottens län, beskrivs här med fokus på paleontologi och sedimentologi. Två nya arter av brachiopoder (Acrotretida) upptäcktes. Tingitanella vilhelminia n. sp. utökar släktet med ytterligare en art och utökar även den geografiska distributionen av släktet till Sverige. Anabolotreta furcatus n. sp. är den första medlemmen av släktet som beskrivits från Sverige och utökar den stratigrafiska spännvidden till lägre mellersta Kambrium. A. furcatus har även en skalstruktur med förgrenande pelare som beskrivs för första gången. En trilobit upptäcktes vid lokalen, Acadoparadoxides torelli, vilket tyder på att exponeringarna vid Björnberget tillhör övre delen av superzonen Acadoparadoxides (Baltoparadoxides) oelandicus. Faunan är artfattig i jämförelse med vad som tidigare har beskrivits från Jämtland och reflekterar en depositionsmiljö på den yttre kontinentalsockeln med ett lågt inflöde av klastiska sediment. Den sedan tidigare kända lokalen vid Granberget, nära lokalen vid Björnberget, beskrivs häri med avseende på paleontologi och sedimentologi. Faunan vid Granberget kan utökas med två nya arter av agnostider, Hypagnostus lingula och Hypagnostus mammillatus, till att totalt innehålla sex arter av trilobiter. Depositionsmiljön påverkades periodvis av stormar som avsatte kalkstenslager bestående av skelettdelar. Alunskiffern har förlorat majoriteten av dessa strukturer under diagenes som annars återfinns i kalkstenskonkretionerna.
20

Taxonomy, biodiversity and biogeography : Tardigrada and Antarctic meiofauna

McInnes, Sandra J. January 2010 (has links)
The main subject of my papers has been the phylum Tardigrada, with particular emphasis on the Antarctic fauna. While this is one of the ‘lesser known phyla’ the group forms an important element of Antarctic non-marine ecosystems. My work has centred on four interrelated themes: i) taxonomy, predominantly Tardigrada and with an Antarctic bias though including wider global species and high taxon groupings (I have also worked on other taxa such as Fungi-imperfecti and freshwater invertebrates); ii) biodiversity of tardigrades, particularly Antarctic habitats; iii) data-based studies based on the terrestrial Tardigrada and Antarctic freshwater crustaceans; and iv) biogeographic analysis of these databases. The thesis presented consists of papers published in major, peer-reviewed journals, along with book chapters published and in press. Several of my papers have been cited 10-30 times according to the ISI Web of Science citation system. Highlights of my work include being the first to publish a paper on the global terrestrial biogeography of a phylum and showing the extant limno-terrestrial tardigrade fauna reflect the early tectonic break-up of the Laurasia, West and East Gondwana super continents between 65 and 135 million years ago.

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