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Full-Text Articles in Life Sciences
Taxonomy And Systematics Of The New Zealand Pselaphini (Coleoptera: Staphylinidae: Pselaphinae), Brittany Elin Owens
Taxonomy And Systematics Of The New Zealand Pselaphini (Coleoptera: Staphylinidae: Pselaphinae), Brittany Elin Owens
LSU Doctoral Dissertations
The New Zealand (NZ) Pselaphini was revised at the species level, a phylogenetic analysis was performed using morphological data, and first steps were taken towards the construction of a molecular analysis of the tribe. Eight new genera and 33 new species were discovered from specimens collected from the NZ mainland, offshore islands, Chatham Islands and the Subantarctic Islands. Of the 13 species originally described in the genus Pselaphus by Thomas Broun during the late 19th and early 20th centuries, all were either reassigned to the genera Pselaphaulax and Pselaphogenius, or were placed into new genera. Three names …
Geographic Population Structure And Taxonomic Identity Of Rhinichthys Osculus, The Santa Ana Speckled Dace, As Elucidated By Nuclear Dna Intron Sequencing, Liane Raynette Greaver
Geographic Population Structure And Taxonomic Identity Of Rhinichthys Osculus, The Santa Ana Speckled Dace, As Elucidated By Nuclear Dna Intron Sequencing, Liane Raynette Greaver
Electronic Theses, Projects, and Dissertations
Rhinichthys osculus (Cyprinidae), the speckled dace, is the most widely distributed freshwater fish in the western United States. The southern California populations of R. osculus are identified as the Santa Ana speckled dace (SASD), though the SASD has not yet been formally recognized as a distinct taxon. Current mtDNA analysis performed in the Metcalf Lab has shown a reciprocally monophyletic relationship among three California regions; southern, central coast, and Owens Valley. Similarly, microsatellite genotyping has shown significant levels of geographic population structure. The purpose of this study was to provide nuclear DNA sequence data to determine the taxonomic status of …
A Taxonomic Revision Of The Genus Burmeistera (Campanulaceae) In Ecuador, Brock Mashburn
A Taxonomic Revision Of The Genus Burmeistera (Campanulaceae) In Ecuador, Brock Mashburn
Theses
The genus Burmeistera (Campanulaceae) consists of approximately 120 species of herbaceous trailing shrubs, found mostly in cloud forests from Guatemala to Peru. Taxonomic work is difficult for the genus because of its relatively recent diversification (5–12 mya) and the morphological lability of its species. The last monograph for the genus was completed in 1943, followed periodically by country-level treatments. For Ecuador, the most recent treatment of Burmeistera was nearly 40 years ago, in Stig Jeppesen’s 1981 treatment in the Flora of Ecuador. Jeppesen’s treatment recognized 32 species and subspecies. Since then, nine new species have been described and hundreds of …
Niche Shifts, Species Distributions, And Genetic Diversity In Gymnophthalminae Lizards, With A Focus On Microclimates And Thermophysiology, Maria Strangas
Niche Shifts, Species Distributions, And Genetic Diversity In Gymnophthalminae Lizards, With A Focus On Microclimates And Thermophysiology, Maria Strangas
Dissertations, Theses, and Capstone Projects
The environmental niche is a central organizing concept in the study of ecology and evolution, as the environmental conditions in which species can persist (their fundamental niches) and the conditions in which they occur (their realized niches) can shape spatial and temporal patterns of biodiversity at multiple scales. How organisms at different levels of biological organization are affected by environmental heterogeneity has consequences for the distribution of genetic and phenotypic diversity, yet the mechanisms through which this occurs are poorly studied. In this dissertation, I present three research chapters that explore how species’ traits and their microclimatic environments shape biodiversity …
Systematics And Biogeography Of The Cortinarius Violaceus Group And Sequestrate Evolution In Cortinarius (Agaricales), Emma Harrower
Systematics And Biogeography Of The Cortinarius Violaceus Group And Sequestrate Evolution In Cortinarius (Agaricales), Emma Harrower
Doctoral Dissertations
Phylogenetics is a powerful tool used for illuminating the diversity of life on Earth, their evolution and their ecology. I created a multi-gene phylogenetic tree of Cortinarius section Cortinarius and uncovered five previously overlooked species, increasing the number of species in the section from seven to twelve. All members of the clade possess both cheilocystidia and pleurocystidia and possess a pigment known as (R)-39,49-dihydroxybphenylalanine. Ancestral state reconstruction estimated that the ancestral host was most likely an angiosperm, switching hosts when encountering novel host species in new lands, and only C. violaceus associating with the Pinaceae in North America. Biogeographic analysis …
Tropical Trees As Islands: Diversity Accumulation Of Armored Scale Insects (Hemiptera: Diaspididae) On Trees As A Function Of Forest Age, Hannah Shapiro
Tropical Trees As Islands: Diversity Accumulation Of Armored Scale Insects (Hemiptera: Diaspididae) On Trees As A Function Of Forest Age, Hannah Shapiro
Undergraduate Honors Theses
Armored scale insects (Hemiptera: Diaspididae) are some of the most invasive insects in the world. These cryptic plant parasites are most often encountered in managed agricultural ecosystems, but very little is known about their distribution, abundance, and diversity in tropical rainforest canopies, where they are likely to have their highest diversity. Because these ubiquitous insects are extreme generalists with undirected dispersal, their diversity (alpha and beta) accumulation can conceivably be modeled according to tenets derived from island biogeography theory. For example, one expectation is that older established trees should boast a higher species diversity and abundance than younger ones. Other …
A New Adaptive Landscape: Urbanization As A Strong Evolutionary Force, Lauren Christie Breza
A New Adaptive Landscape: Urbanization As A Strong Evolutionary Force, Lauren Christie Breza
Masters Theses
Urbanization is rapidly increasing as human population growth steadily grows, but there is little consensus of the ecological consequence of this population shift and almost no information of the evolutionary consequences for local biodiversity. Nearly two-thirds of the world’s population will live in city centers by 2050 with profound impacts on landscapes that can act as important agents of selection. This study aims to identify 1) the net effect of urbanization on species richness, 2) how phylogenetic diversity varies between urban and rural sites, and 3) the strength of urbanization as a selection pressure. First, a meta-analysis was conducted in …
Systematics Of The African River Frog Genus Amietia (Anura: Pyxicephalidae) From Eastern Democratic Republic Of The Congo, Thornton Robert Larson
Systematics Of The African River Frog Genus Amietia (Anura: Pyxicephalidae) From Eastern Democratic Republic Of The Congo, Thornton Robert Larson
Open Access Theses & Dissertations
The African river frog genus Amietia is found near rivers and other lentic water sources throughout central, eastern and southern Africa. Because the genus includes multiple morphologically conservative species, taxonomic studies of river frogs have been limited. We sampled 49 individuals of Amietia from multiple localities in and near the Albertine Rift (AR) of Burundi, Democratic Republic of the Congo and Uganda. We utilized single-gene (16S) and concatenated (12S, 16S, cytochrome b and RAG1) gene-tree analyses and coalescent species-tree analyses to construct phylogenetic trees. Two divergence dating approaches were used in BEAST, including secondary calibration points with 12S, 16S and …
Molecular Systematics Of The Subfamily Phasiinae (Diptera: Tachinidae), Jeremy Daniel Blaschke
Molecular Systematics Of The Subfamily Phasiinae (Diptera: Tachinidae), Jeremy Daniel Blaschke
Masters Theses
The subfamily Phasiinae (Diptera: Tachinidae) is composed of obligate endoparasitoid flies that attack heteropteran insects, many of which are important agricultural pests. To lay a foundation for future studies in phasiine life history and their potential for use as biological control agents, the phylogenetic relationships within Phasiinae were explored using nucleotide sequences of two genes, CAD and LGL. A total of 63 taxa for CAD and 73 taxa for LGL were included in the analyses, representing 58 genera. Maximum likelihood inference methods were employed to reconstruct phylogenetic relationships in separate analyses of each gene and in a combined dataset. Phylogenetic …
Systematics Of Leptopelis (Anura: Arthroleptidae) From The Itombwe Plateau, Eastern Democratic Republic Of The Congo, Francisco Portillo
Systematics Of Leptopelis (Anura: Arthroleptidae) From The Itombwe Plateau, Eastern Democratic Republic Of The Congo, Francisco Portillo
Open Access Theses & Dissertations
Leptopelis, a genus of Central African treefrogs, includes 51 species that live in tropical forests and savannas. Currently, only two species of Leptopelis are known from the poorly explored Itombwe Plateau in eastern Democratic Republic of the Congo (DRC). Itombwe is renowned among conservationists for its rich and endemic amphibian fauna, including: Xenopus itombwensis, Chrysobatrachus cupreonitens, Laurentophryne parkeri, Hyperolius leleupi and at least three species of Arthroleptis. Evolutionary relationships of Itombwe Leptopelis were examined by sequencing two mitochondrial genes (16S: 557 bp [base pairs], cyt b: 620 bp) and one nuclear gene (RAG1: 761 bp). Results recovered strong support for …
A Taxonomic Revision Of The New World Hypoponera Santschi, 1938 (Hymenoptera: Formicidae), Shawn Thomas Dash
A Taxonomic Revision Of The New World Hypoponera Santschi, 1938 (Hymenoptera: Formicidae), Shawn Thomas Dash
Open Access Theses & Dissertations
The New World taxa of the pantropic ant genus Hypoponera (Ponerinae: Ponerini) is revised for the first time. The 55 previously recognized taxa have been evaluated using morphological and, when possible, ecological and biogeographical data to resolve taxon validity and species limits. Currently I recognize 42 species of Hypoponera , a number of which are new. I propose the following taxonomic outline: Hypoponera agilis (Borgmeier), Hypoponera aliena (F. Smith), Hypoponera antoniensis (Forel) stat. nov., Hypoponera apateae sp. nov., Hypoponera capilosa sp. nov., Hypoponera clinei sp. nov., Hypoponera clavatula (Emery) [= fiebrigi (Forel) syn. nov., = neglecta (Santschi) syn. nov.], Hypoponera …