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The Mealybugs (Hemiptera: Coccoidea: Pseudococcidae) Of Egypt, Gregory A. Evans, S. Abd-Rabou

Insecta Mundi

The Egyptian fauna of mealybugs (Hemiptera: Coccoidea: Pseudococcidae) is reviewed and an illustrated key to the 30 genera and 54 species is provided. Phenacoccus madeirensis Green is reported for the first time in Egypt. A new genus, Ezzatacoccus Evans and Abd-Rabou, is described and illustrated with Amonostherium arabicum Ezzat, 1960 designated as its type species. Octococcus salicicola Priesner and Hosny, 1935 is reinstated as a valid taxon and transferred to Misericoccus Ferris, new combination. Ripersia cressae Hall is transferred to Maconellicoccus Ezzat, new combination and Planococcus lindingeri (Bodenheimer) is transferred back to Formicococcus Takahashi, revised status.

Discovery Of An Introduced Florida Flagfish (Jordanella Floridae) Population In Coastal Mississippi, Robert Ellwanger, Samuel E. Hunt, Calvin R. Rezac, Matthew D. Wagner

Southeastern Fishes Council Proceedings

The recent discovery of Jordanella floridae (Florida Flagfish) in Harrison County, Mississippi represents the first known occurrence of the species in the state. Native along the Atlantic and Gulf Coasts of Florida from Jacksonville to Tallahassee, this species has been introduced outside of its range via aquarium introductions. We hypothesize that an aquarium introduction was also the source of the newly discovered population, which has persisted at the location since 2020. Multiple collections of the species have been taken from a small waterbody which has a direct connection to the Tchoutacabouffa River (25mm-47mm TL). While it is unknown if this …

Behavioral Response To Conspecific Sounds In Loricariid Catfishes (Pterygoplichtys Pardalis And Otocinclus Vittatus), Hephzibah Obafunmiso

Masters Theses & Specialist Projects

Sound production is a means of communication among many fish species. In fishes, sound is produced through various mechanisms, but in the family Loricariidae, known as armored suckermouth catfishes, sound is produced primarily through pectoral fin spine stridulation. Previous experiments have described the sounds produced and shown the mechanism of sound production in two species of loricariid catfishes, Pterygoplichthys gibbiceps and Otocinclus affinis, but the functional significance of loricariid sounds is still unknown. To address this question, I examined the behavioral responses of Pterygoplichthys pardalis and Otocinclus vittatus to conspecific calls. Individual fish (N=10 for P. pardalis) or groups …

A Phylogenetic Analysis Of The Leuctra Ferruginea (Walker 1852) Species Group (Plecoptera: Leuctridae), Madison Layer

Masters Theses & Specialist Projects

Leuctra Stephens, 1836 is a genus of Plecoptera (Leuctridae) distributed widely across the Northern Hemisphere, with approximately 210 species reported from eastern North America, Europe, northern Africa, and sporadically across Asia. Eastern North America harbors a small proportion of the global Leuctra fauna (ca. 15% = 31 species), most of which occur in the ancient Appalachian Mountains and unglaciated landscapes in the southeastern USA. Nearctic Leuctra species, except for L. moha and L. crossi, have been divided into five species groups based on external male morphological characteristics. Current phylogenies of Nearctic Leuctra are partial and preliminary, and no comprehensive …

Assessing The Effect Of Reservoirs On Gene Flow In The Southern Two-Lined Salamander (Eurycea Cirrigera), Anna Favalon

Masters Theses & Specialist Projects

Biodiversity is an essential component of natural environmental dynamics. Unfortunately, diversity is threatened by human activities and relies on conservation efforts. An important aspect of biodiversity conservation lies in protecting population connectivity and gene flow. In the mid-1900s, many Kentucky rivers were dammed, creating deep, lentic reservoirs in the valleys once occupied by dynamic, lotic rivers. For species inhabiting the rivers and associated tributaries, the central reservoirs may reduce connectivity among populations and impose a barrier to gene flow. The connectivity of populations on landscapes altered by the creation of reservoirs can be assessed by merging the principles of landscape …

Mammalian & Avian Community Response To African Elephant (Loxodonta Africana) Habitat Modification In Southeastern Kenya, Dakota Vaccaro

Masters Theses & Specialist Projects

African elephants (Loxodonta africana) play a significant role in the modification of their habitat, foremost by decreasing woody vegetation cover and density and in some parts of Africa high elephant densities damage small sanctuaries and preserves. For wildlife that depend on forested patches, this increased modification could lead to displacement and/or decreases in abundance. If suitable habitat is not available elsewhere, elephants and other wildlife may move closer to humans in search of resources, which can result in increased human-wildlife conflict. Evaluating this impact was one of the goals of the Elephants and Sustainable Agriculture in Kenya (ESAK) …

The Effect Of Symbioses Between Mold Mites (Acaridae: Tyrophagus Putrescentiae) And Aspergillus Flavus On Their Respective Populations In Stored Maize., Paige Pionke Cummins

Graduate Theses and Dissertations

Zea mays is the most commonly grown grain in the world and is used for animal feed, human consumption, and the creation of other products such as ethanol and bioplastics. Contamination of stored maize with stored grain invaders can lead to loss of revenue, reduced food availability, and potential health complications. Two such storage invaders; the mold mite Tyrophagus putrescentiae and the fungus Aspergillus flavus can work as symbionts within the grain storage system. To determine resulting population growth from this symbiosis, maize was inoculated with three treatments: A. flavus with no mites, T. putrescentiae with no fungus, and both …

Generation Z’S Perceptions Of Hunting And Conservation Efforts In Arkansas, Hannah Ferguson

Graduate Theses and Dissertations

Hunting participation numbers have steadily declined since the 1980s and Generation Z is not engaging in hunting. Hunting is one of the most effective tools for managing wildlife populations and ensuring the success and local ecosystem conservation. Many wildlife stewardship institutions, such as Arkansas Game and Fish Commission in Arkansas, are funded by sales taxes imposed on firearms, ammo, and archery equipment. With a decline in hunting participation, it is imperative state-run wildlife stewardship organizations and other hunting institutions learn the best practices for communicating with younger generations. This study sought to understand Generation Z’s perceptions of hunting and conservation …

Comparison Of Vegetative Community And Soil Organic Matter Depth Among Reference Sites And Two Restored Wetlands In The Coastal Plain Of South Carolina, Jessica Clark

All Theses

Wetland loss and degradation from agriculture, urbanization, forestry, and mining is a global issue. South Carolina alone has lost over 27% of its wetlands. This historical wetland loss and climatic changes and impacts make restoring wetlands critical for the state. In restoration, understanding the difference in restored and reference wetland’s vegetation and soil organic matter depth can be crucial in assessing the recovery rate and determining environmental functions and services. The main objectives for our research were to determine differences in soil organic matter depth and vegetative community between the restored Brosnan Forest wetlands, the headwater flats and headwater slopes, …

Overcoming Barriers To Aquatic Plant Restoration: Addressing Gaps In Species Identification And Planting Techniques In The Intermountain West, Kate A. Sinnott

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Aquatic ecosystems provide many critical and economically valuable benefits, including drinking water, food, recreational opportunities, and water supply for irrigation and agriculture. However, the health of these systems has been severely impacted by human activities such as pollution, land conversion, and introductions of harmful species. Restoring native aquatic plants can help reverse this damage and reestablish benefits, though it is not a common practice. With an objective to increase capacity for aquatic plant restoration in the Intermountain West, I identified and addressed two major barriers: 1) a lack of confidence in aquatic species identification among wetland professionals, and 2) underdeveloped …

Evidence Of Competitive Release Following Overstory Mortality In A Semi-Arid Piñon-Juniper Woodland, Corrie D. Gonzalez

Biology ETDs

Extreme temperatures and severe drought events have led to widespread tree mortality worldwide. In semi-arid regions of the Southwest United States, these events pose a significant threat to piñon-juniper (PJ) woodlands. We studied the effects of piñon and juniper mortality on the growth and physiology of existing saplings in PJ woodlands by analyzing water status, photosynthetic activity, and tissue chemistry to gain insights into these impacts. Juniper saplings exhibited improved water status and water use efficiency in response to overstory mortality, whereas piñon saplings did not. Additionally, both piñon and juniper saplings exhibited increased photosynthetic rates, increased photosynthetic capacity, and …

Resolving The Paradox Of Polyploidy: Underexplored Facets Of Polyploid Plants, Benjamin P. Gerstner

Biology ETDs

Polyploidy, or whole genome duplication, is a common phenomenon in plants, but the establishment and persistence of mixed-ploidy populations remains a paradox. This dissertation explores factors that contribute to the persistence and establishment of mixed-ploidy populations in nature. The first chapter investigates the role of unreduced gametes in neopolyploid establishment and finds that variability in their formation rate can have a significant impact on polyploid establishment and persistence. The second chapter searches for evidence of soil microbes exhibiting ploidy-specificity, a pre-condition for microbe-mediated niche differentiation, a possible stabilizing mechanism contributing to ploidy coexistence. Finally, the third chapter tests for microbe-mediated …

Investigation Of Orthohantavirus Genetics In Rodent Reservoirs And Clinical Samples, Samuel Melvin Goodfellow

Biomedical Sciences ETDs

Orthohantaviruses are negative-sense, single stranded RNA viruses with trisegmented genomes that can cause severe disease in humans and are carried by several host reservoirs throughout the world. In the United States, Sin Nombre orthohantavirus (SNV) is the primary cause of hantavirus cardiopulmonary syndrome (HCPS) with a fatality rate of ~36% and the highest cases occuring in the southwest region. The primary SNV host reservoir is thought to be the western deer mouse, Peromyscus maniculatus, however it has been shown that other rodents can carry different orthohantaviruses. We designed a pan-orthohantavirus detection tool to survey several small mammal populations throughout New …

Shedding In The Timber Rattlesnake: Natural Patterns, Endocrinological Underpinnings, Temporal And Energetic Effort, And Integration As A Reptilian Life History Trait, Maxwell D. Carnes-Mason

Graduate Theses and Dissertations

The semi-frequent replacement of the epidermis (ecdysis) is a characteristic trait of reptiles. Whereas all reptiles regularly engage in some degree of skin shedding, skin morphology in snakes necessitates the synchronous replacement of the entire epidermis and facilitates the subsequent removal of the old layer as a single sheet. To date, the ubiquitous process has garnered little attention from researchers because snakes shed with unpredictable timing and frequency and are exceedingly cryptic during ecdytic cycles; previously impeding detailed physiological or ecological investigations of the process in the clade. Because of the lack of study, ecdysis is often viewed as a …

The Influence Of Climate And Landscape On Allocapnia Mohri Distribution In Arkansas, Brianna Leigh Annaratone

Graduate Theses and Dissertations

Stoneflies are a globally threatened aquatic insect order. In Arkansas, a diverse group of winter stonefly (Capniidae: Allocapnia) have not been surveyed since the 1980s, likely because species-level identification requires the rarely-collected adult form. Allocapnia mohri, a regional endemic, was previously commonly found in mountainous, intermittent streams from the Ouachita Mountains ecoregion north to the Ozark Highlands, but no species distributional models including land use or climate variables exist to our knowledge. We collected adults from 70 stream reaches from the historic Arkansas range from November to April 2020 and 2021. We modeled distributions using random forest (RF) models populated …

New Species Of Dryolestoid From The Late Cretaceous Allen Formation And Implications For South American Faunal Diversity., Brigid Erin Connelly

Electronic Theses and Dissertations

Dryolestoids are extinct cladotherians mammals from the Jurassic and Cretaceous periods. I describe a collection of dryolestoid specimens from the Late Cretaceous localities of Cerro Tortuga (Allen Formation), Anfiteatro 1, and Shining (both La Colonia Formation) from Patagonia, Argentina. Using comparative morphology, I identify a new species of meridiolestidan dryolestoid based on eleven specimens across both formations. The new species’ recovery from La Colonia Formation represents the first dryolestoid connection between the two approximately contemporaneous formations. The species’ morphology may represent an ecological shift within Meridiolestida from insectivory to herbivory, showing a transition in characters between the plesiomorphic sharp-toothed meridiolestidans …

The Importance Of Soil Carbon In Large-Scale Shrub Removal Practices In The Chihuahuan Desert, Kathleen Schaeffer

Open Access Theses & Dissertations

Shrub encroachment is a worldwide phenomenon that affects multiple biomes at different ecological and anthropogenic levels. In dryland ecosystems, shrub encroachment is a noted concern amongst land managers, as it can lead to a loss of soil resources and biodiversity. To mitigate the negative effects of shrub encroachment in Drylands, land managers can implement large-scale shrub removal practices. These land restoration practices can shift landscapes to novel ecosystems, where resulting plant communities can vary following treatments. Grass recovery or increasing herbaceous cover is often a primary goal of these treatments, however predicting which sites may show higher grass responses to …

Diversity And Lifestyle In The Rotifera, Patrick D. Brown

Open Access Theses & Dissertations

Broad questions regarding community assembly and lifestyle evolution remain unanswered. To answer these questions I used rotifers, common primary consumers present in inland waters. Rotiferan presence in nearly all freshwaters makes them an ideal study system to address questions of metacommunity ecology. Additionally, rotifers possess diverse lifestyles, including sessile, swimming, colonial and solitary forms, allowing them to be used as models of lifestyle evolution. In Chapter 1, I address metacommunity ecology by focusing on inland waters of the Chihuahuan Desert as a study system and investigated rotifer community assembly therein through two published works, Brown et al., 2020 and 2021. …

Tidal Flooding In The Mid-Atlantic Region Of The Us: Water Quality Effects In The Lower Chesapeake Bay, Alfonso Macias Tapia

OES Theses and Dissertations

Many coastal areas around the globe suffer from nutrient pollution and its environmental, social, and economic consequences. Nutrient inputs can come from point (e.g., the end of a pipe) and nonpoint sources, from which the former are better constrained as sampling need only be conducted at a discharge point. Given the temporal and spatially extensive nature of tidal flooding events, they can represent another type of nonpoint source of nutrients to adjacent water bodies heretofore, unexamined and quantified. Most studies examining impacts of tidal flooding have focused on threats to resources on land, such as urban infrastructure and human health …

Increases In Uvr Exposure: Local Adaptation Of A Bdelloid Rotifer, Maribel J. Baeza

Open Access Theses & Dissertations

Aquatic species living in ephemeral habitats without a continual influx of dissolved organic carbon (DOC) are at increased risk of the effects of ultraviolet radiation (UVR) as the climate changes. Climate change is predicted to cause changes in DOC, some habitats will experience extended periods of drought and reduced input from DOC sources, and other environmental features that increase UVR reaching aquatic habitats. UVR can cause damage to cellular structures and biomolecules such as DNA, proteins, and lipids. The pigmented bdelloid Philodina sp. (Philodina) found in rock pools in the Chihuahuan Desert naturally experiences high UVR, yet it appears to …

The Ecological Effects Of Nitrogen Enrichment In Aridlands, Jennifer Holguin

Open Access Theses & Dissertations

Anthropogenic nitrogen (N) deposition is one of the most prominent factors driving global change. Across the globe, N deposition has driven major changes in terrestrial ecosystems, such as declines in plant biodiversity, enhanced exotic plant growth, and changes to biogeochemical processes involved in carbon and nutrient cycling. While noteworthy effort has been put forth to investigate the effects of N deposition on terrestrial ecosystems, a disproportionate number of N addition studies have been conducted in temperate mesic systems. Thus, we lack a holistic and mechanistic understanding of how N deposition impact aridland ecosystems. Additionally, our predictions of the effects of …

Co-Flowering Community Effects On The Relative Contribution Of Pollen Quantity And Quality Limitation To The Reproductive Success Of Four Clarkia Species, Emma Moore

Electronic Theses and Dissertations

More than 60% of plant populations experience low pollen availability which limits seed production (pollen limitation). Pollen limitation occurs due to low quantity or quality of pollen delivered to stigmas. Despite its ubiquity in nature, to date we still have limited understanding of the drivers of pollen limitation in plant communities. Plants typically occur in diverse communities where pollinator sharing is common and can influence quality and quantity aspects of pollen limitation. Co-flowering species can attract larger numbers of pollinators or they can compete for pollinators affecting pollen loads on stigmas. Pollinator competition may also lead to higher rates of …

The Old Family Clock: Exploring High Variation Of Chronotype In The Common House Spider, Parasteatoda Tepidariorum, Caitlin Jones

Electronic Theses and Dissertations

Circadian rhythms are often tightly confined around a mean of 24 hours with little variation in traditional model organisms in the absence of environmental time cues. Some spider species fall well outside this normal range with mean periods of 18 hours and variation around these means of 6 hours or more. This extreme variation in circadian rhythm is not well-understood and is the focus of the current study. Using Parasteatoda tepidariorum as a model organism, we investigated whether variation in eight circadian parameters could be explained by genetic variability, environmental conditions, or an endogenous feature of the circadian system of …

Impacts Of Urbanization On Pollination Success For Common Milkweed (Asclepias Syriaca), David Rockow

Electronic Theses and Dissertations

Urbanization is among the greatest threats to biodiversity on the planet, and is projected to increase in magnitude in coming years. This growing threat makes it important to better understand how urbanization may impact vital ecosystem services, such as pollination. Studies on the impact of urbanization on pollination vary wildly in their findings. This study analyzed multiple aspects of pollination success in common milkweed populations varying in urbanization level, including insect community composition, pollen removal/deposition, and fruit/seed production. By analyzing multiple pollination aspects we can determine the overall mechanism in which urbanization instills on the entire pollination process. Overall, urbanization …

Geometric Morphometric Analysis Of Modern Viperid Vertebrae Facilitates Identification Of Fossil Specimens, Lance D. Jessee

Electronic Theses and Dissertations

Snake vertebrae are common in the fossil record, whereas cranial remains are generally fragile and rare. Consequently, vertebrae are the most commonly studied fossil element of snakes. However, identification of snake vertebrae can be problematic due to extensive variation. This study utilizes 2-D geometric morphometrics and canonical variates analysis to 1) reveal variation between genera and species and 2) classify vertebrae of modern and fossil eastern North American Agkistrodon and Crotalus. The results show that vertebrae of Agkistrodon and Crotalus can reliably be classified to genus and species using these methods. Based on the statistical analyses, four of the …

An Early Pliocene Fish Assemblage From The Southern Appalachians: Ichthyofauna Of The Gray Fossil Site, Shay Maden

Electronic Theses and Dissertations

The Gray Fossil Site (GFS) preserves an early Pliocene sinkhole pond that accumulated a rich flora and vertebrate fauna. Fossils of fish are incredibly common at GFS, representing thousands of specimens recovered to date. Comparison with extant species reveals a depauperate freshwater fish fauna consisting of only two species: Lepomis sp. and Micropterus sp. The absence of fishes that are ubiquitous in modern streams suggests no perennial surface hydrologic connection between the Gray Fossil Site and the nearby Holston River. Limited opportunities for dispersal into the pond and deleterious conditions such as eutrophy and high competition may have resulted in …

Leveraging Eco-Evolutionary Models For Gene Drive Risk Assessment, Matthew A. Combs, Andrew J. Golnar, Justin M. Overcash, Alun L. Lloyd, Keith R. Hayes, David A. O'Brochta, Kim M. Pepin

United States Department of Agriculture Wildlife Services: Staff Publications

Engineered gene drives create potential for both widespread benefits and irreversible harms to ecosystems. CRISPR-based systems of allelic conversion have rapidly accelerated gene drive research across diverse taxa, putting field trials and their necessary risk assessments on the horizon. Dynamic processbased models provide flexible quantitative platforms to predict gene drive outcomes in the context of system-specific ecological and evolutionary features. Here, we synthesize gene drive dynamic modeling studies to highlight research trends, knowledge gaps, and emergent principles, organized around their genetic, demographic, spatial, environmental, and implementation features. We identify the phenomena that most significantly influence model predictions, discuss limitations of …

Tropical Understory And Canopy Twig Ants (Pseudomyrmex): Natural History, Sensory Homing, And Neuroecology., Daniella Prince

Electronic Theses and Dissertations

In this dissertation, I examined the behavior of foraging twig ants, explored the sensory profile of their homing behavior, and investigated the role of habitat use in shaping the sensory neurobiology of species within the genus Pseudomyrmex (Hymenoptera: Formicidae). In chapter one, I reviewed the ecology of Pseudomyrmex, and introduced the focal species, P. boopis, a neotropical understory-dwelling twig ant. In chapter two, I described the natural history of P. boopis on Barro Colorado Island, Panama—specifically, their nesting habits, activity rhythm, and foraging behavior on understory surfaces. Pseudomyrmex boopis colonies were diurnal and nested in dead twigs in …

Western Pearlshell (Margaritifera Falcata) Extirpation In The Smith River, Montana, With A Possible Link To Warming Water Temperatures, David M. Stagliano

Western North American Naturalist

Western pearlshell (Margaritifera falcata) populations are in decline across the species’ range in western North America. In 2008, Montana categorized the western pearlshell as an imperiled species of concern (S2) based on reduced detections at historically occupied sites and few viable populations. Between 2004 and 2014, we surveyed 24 Smith River reaches (61 total sites in the watershed) for the presence of western pearlshell populations. Despite historical and anecdotal descriptions of abundant western pearlshell in the Smith River, intensive structured surveys between 2004 and 2007 documented only 4 sections with low-density, nonviable western pearlshell populations (<10 individuals, large size classes [average total length = 70 mm], with no signs of recruitment). In 2014, we revisited these occupied sites to repeat surveys (expending significantly more search time) and observed no live individuals. This was surprising given that, although those populations would certainly die out without recruitment, older individuals can oftentimes persist for decades. Therefore, we consider the western pearlshell mussel extirpated from the Smith River watershed. We reviewed long-term USGS gage discharge and temperature data near the western pearlshell populations to evaluate the potential causal factors for, and timing of, the extirpation. From 3 July to 3 August 2007, water temperatures were at or above the thermal stress levels of the western pearlshell (>25 °C, …

Fishing Out Nutrients: The Spatiotemporal And Ecological Dynamics Of Fishery-Based Nutrient Extraction, Adrián A. González Ortiz

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Marine fisheries are one of the most impactful human activities on the planet. Since the 1950s, marine fisheries have removed billions of metric tons of marine biomass leading to substantial declines in many fish populations. Among their impacts, we have begun to investigate the role of fisheries in disrupting marine nutrient cycles. Specifically, removing biomass can change nutrient cycles by reducing the amount of nutrients stored within animal biomass.

No studies have investigated the large-scale geographical and ecological contexts of nutrient removal by fisheries over a large timescale. For my thesis, we compiled data on fishery-targeted organisms' carbon, nitrogen, and …