Biology

Dictyla ainsliei (Drake and Poor) is transferred to the genus Ambotingis Drake and Ruhoff, redescribed, and reported from Costa Rica for the first time. Ambotingis senta (Drake and Hambleton) is also diagnosed, and a key for the separation of the two species is provided.

The genera of Tingidae of the neotropics are herein diagnosed and a key for their identification is also provided. Five new genera are described from Central America, two from Panama, two from Costa Rica, and one new genus is described from Mexico. This brings the total of neotropical genera to 74. One new species, Mexibyrsa woolleyi is described from Mexico. The Tingidae of southern Central America (Nicaragua, Costa Rica, and Panama) are reviewed in detail. There are now 153 described species spread among 43 genera. Thirty-two new species from southern Central America are described. Identification keys are provided for all species found in the study region. iv ACKNOWLEDGMENTS Over the course of my Master's degree I have made many contacts and friends in and outside of the field of entomology. There are literally countless people that have made this work possible and I wish to thank all who have participated, assisted, and provided for this project. Whenever possible, I have tried to record all individuals with their contributions, and to the best of my knowledge, they are listed below.

The tingids or lace bugs (Hemiptera: Heteroptera, Cimicomorpha: Tingidae) are small sized insects with phytophagous habits and a cosmopolitan distribution, and some taxa are of agriculture importance. In this paper, a revised and updated checklist of the family Tingidae registered from Venezuela is presented and discussed. Up to now, 67 lace bugs species have been recorded, distributed into 3 subfamilies, 3 tribes and 26 genera, including subfamily Cantacaderinae, Tribe Phatnomatini, genera Zetekella (1 species) and Phatnoma (2 species); subfamily Tinginae, Tribe Litadeini, genus Stragulotingis (2 species); and the Tribe Tingini, genera Acanthocheila (1 species), Amblystira (3 species), Atheas (1 species), Corythaica (4 species), Corythucha (6 species), Dictyla (5 species), Dyspharsa (1 species), Eurypharsa (1 species), Gargaphia (4 species), Leptocysta (1 species), Leptodictya (4 species), Leptopharsa (5 species), Pachycysta (2 especies), Paraceratotingis (1 species), Phymacysta (1...

Se revisan los géneros de chinches de encaje (Tingidae) del Nuevo Mundo pertenecientes al complejo Tigava. Se describen dos nuevos géneros y especies Mexicotingis brailovskyi de México, y Paraceratotingis convergens, de Venezuela. Se brindan diagnosis, descripciones, y fotos en color de los nuevos taxa, diagnosis y fotografías de la cabeza y el pronoto de todos los géneros, una lista actualizada de las distribuciones de todas sus especies, y una clave para géneros para distinguir estos Tingidae estrechamente emparentados.The lace bug (Tingidae) genera belonging to the New World Tigava complex are reviewed. The two new genera and new species Mexicotingis brailovskyi, from México, and Paraceratotingis convergens, from Venezuela, are described. Diagnoses, descriptions, and digital color photographs of the new taxa, diagnoses and digital photographs of the heads and pronota of all genera, an updated checklist and distributions of the included species, and a key to genera are provided to...

Native bees such as bumble bees are important pollinators of wildflowers as well as many agricultural crops. However, recent evidence demonstrates that bumble bees are in decline in the United States. Bumble bees can utilize semi-natural areas such as gardens, hedgerows, and roadsides as habitat. We sought to better understand how bumble bees were using roadside prairie plantings by monitoring their movement within and between roadside habitats. At four sites, bumble bees were caught on roadside wildflowers, marked distinctly, and released. Sampling took place over subsequent days on both sides of the road to determine if bees readily crossed the road. We found that nearly 800 individual bumble bees of four species were collecting either pollen or nectar from roadside wildflowers. While some bees did move linearly within a roadside to find additional flowering resources, others visited the same patch of flowers repeatedly throughout time. This strong site fidelity suggests that road...

A.7. Specimen count and number of orders, families and morphospecies represented in each arthropod functional community at Oakville in year one and year two ……………………………………………………. 83 A.8. Number of families and morphospecies identified in the five orders represented by the most families and morphospecies in each arthropod functional community across years …………………………… 84 A.9. Correlations among year one Oakville arthropod functional community composition and diversity matrices ……………………………………… A.10. Correlations among year two Oakville arthropod functional community composition and diversity matrices …………….

Previous studies suggest that, within particular groups of plant species, biological attributes can be used to predict the potential invasiveness of species that are intentionally introduced for horticultural or agricultural purposes. We examined the broad question of whether commonly available biological information can predict the invasiveness of a wide range of intentionally and accidentally introduced species. We collected information from published floras on 165 pairs of plant species. In each pair, one species originated in Europe and successfully invaded New Brunswick, Canada, and the other was a congeneric species that has not invaded North America. Only three biological characters-lifeform, stem height, and flowering period-and European geographic range were known for all species. We conducted multiple logistic regression analyses using two-thirds (110) of the species pairs and tested the predictive ability of resulting models using the remaining 55 pairs. Although a significant logistic regression model was obtained using the biological attributes, the model could not predict invasiveness of the test species pairs. In contrast, a model using only European range successfully predicted invasiveness in 70% of the test species. The importance of geographic range suggests that prediction of invasiveness on a species-by-species basis is not likely to help stem the flow of accidentally introduced invasive species. Species that are inadvertently picked up and moved to a new location due to their wide distribution are the same species that are likely to succeed in a new environment due to their wide environmental tolerances.

Organisms in highly suitable sites generally produce more offspring, and offspring can inherit this suitability by not dispersing far. This combination of spatial selection and spatial inheritance acts to bias the distribution of organisms toward suitable sites and thereby increase mean fitness (i.e., per capita population increase). Thus, population growth rates in heterogeneous space change over time by a process conceptually analogous to evolution by natural selection, opening avenues for theoretical cross-pollination between evolutionary biology and ecology. We operationally define spatial inheritance and spatial selective differential and then combine these two factors in a modification of the breeder's equation, derived from simple models of population growth in heterogeneous space. The modified breeder's equation yields a conservative criterion for persistence in hostile environments estimable from field measurements. We apply this framework for understanding gypsy moth population persistence amidst abundant predators and find that the predictions of the modified breeder's equation match initial changes in population growth rate in independent simulation output. The analogy between spatial dynamics and natural selection conceptually links ecology and evolution, provides a spatially implicit framework for modeling spatial population dynamics, and represents an important null model for studying habitat selection.

White-footed mice prey on gypsy moth pupae while foraging for other, more abundant food. Mice appear capable of locally extirpating moths since mice exert high predation pressure on sparse pupae and are numerically decoupled from moth populations. Nevertheless, during 23 years of monitoring, moths persisted at scales Ͼ1 ha despite frequent extinctions at smaller spatial scales. We hypothesized that spatially heterogeneous intensity in mouse foraging and/or limited moth dispersal might allow moth persistence. Using a spatially explicit, individual-based, empirically parameterized model, we show that neither spatially heterogeneous predation by mice, nor limited moth dispersal alone allows moth persistence at typical mouse densities. However, synergy between both factors allows moth population persistence at naturally occurring mouse densities. For example, in models with 40 mice/ha, both limited moth dispersal with spatially homogeneous predation risk and spatially heterogeneous predation risk with unlimited moth dispersal had a 0% chance of moth persistence, but the combination of limited dispersal and heterogeneous predation risk resulted in a ϳ75% chance of moth persistence. Furthermore, both for limited moth dispersal with spatially homogeneous predation risk and for spatially heterogeneous predation risk with unlimited moth dispersal, moth persistence was only guaranteed at very low mouse densities, while the combination of limited moth dispersal with heterogeneous predation guaranteed moth persistence within a broad range of mouse densities. The findings illustrate a novel mechanism of ''spatial selection and satiation'' that can enhance rare species persistence under intense incidental predation by generalist predators.

Investigation of host-parasite interactions typically reveals a negative impact of parasitism on the host species. In contrast, mounting evidence indicates that bot fly (Cuterebra sp.) infestation enhances the survival of white-footed mice (Peromyscus leucopus). We propose that life history trade-offs, namely, between reproduction and survival, can explain this counterintuitive observation. By using an extensive data set spanning a decade, 12 sites in two states, and over 30 000 mouse captures, we offer a new perspective on the effects of bot fly parasitism on white-footed mice. Analysis of persistence time corroborated earlier studies that showed significantly higher survival rates of infested mice. Although a higher proportion of infested than uninfested females were in breeding condition, secondary reproductive success appeared to be negatively impacted by parasitism via declines in the number of litters and the total number of offspring produced by infested females. Population growth rates were negatively correlated with infestation prevalence, further indicating a negative effect of parasitism. Based on the negative impact of parasitism on reproduction, we propose that enhanced survival of infested mice can be explained by the diversion of resources from reproduction to body maintenance. Parasite-induced life history shifts in which mice decrease current reproduction to promote future reproduction, such as increasing the age at maturity, may also contribute to the decline in population growth rate observed in years of high infestation prevalence.

We present an exploratory analysis of reported county-specific incidence of Lyme disease in the northeastern United States for the years 1990-2000. We briefly review the disease ecology of Lyme disease and the use of risk maps to describe local incidence as estimates of local risk of disease. We place the relevant elements of local environmental and ecological variables, local disease incidence, and (importantly) local disease reporting in a conceptual context to frame our analysis. We then apply hierarchical linear models of increasing complexity to summarize observed patterns in reported incidence, borrowing information across counties to improve local precision. We find areas of increasing incidence in the central northeastern Atlantic coast counties, increasing incidence branching to the north and west, and an area of fairly stable and slightly decreasing reported incidence in western New York.

Spatial heterogeneity in risk is a critical component of predator-prey interactions. However, at small spatial scales, it is difficult to quantify predation risk without altering it. We used track plates to measure local predation risk created by white-footed mouse (Peromyscus leucopus) foraging activity on oak-forest plots in Millbrook, New York. Live gypsy moth pupae (Lymantria dispar) were placed at 2 heights on trees and monitored for predation. Pupae deployed on trees visited by mice were more likely to be eaten than those on trees not visited. Logistic regression indicated that predation rates on gypsy moth pupae were positively correlated with track activity, indicating that areas of concentrated mouse activity were areas of heightened risk for gypsy moths. Survival of individual oat grains placed on and 50 cm from track plates were not statistically different, indicating that mice exhibited no detectable behavioral reaction toward track plates. We conclude that track plates offer an economical and reliable means of quantifying local risk of attack by terrestrial mammals without substantially altering the spatial distribution of risk.

. How does landscape structure influence landscape connectivity? -Oikos 99: 552-570. We investigated the impact of landscape structure on landscape connectivity using a combination of simulation and empirical experiments. In a previous study we documented the movement behaviour of a specialized goldenrod beetle (Trirhabda borealis Blake) in three kinds of patches: habitat (goldenrod) patches and two types of matrix patch (cut vegetation and cut vegetation containing camouflage netting as an impediment to movement). In the current study, we used this information to construct simulation and experimental landscapes consisting of mosaics of these three patch types, to study the effect of landscape structure on landscape connectivity, using the T. borealis beetle as a model system. In the simulation studies, landscape connectivity was based on movements of individual beetles, and was measured in six different ways. The simulations revealed that the six measures of landscape connectivity were influenced by different aspects of landscape structure, suggesting that: (1) landscape connectivity is a poorly defined concept, and (2) the same landscape may have different landscape connectivity values when different measures of landscape connectivity are used. There were two general predictions that held over all measures of landscape connectivity: (1) increasing interpatch distance significantly decreased landscape connectivity and (2) the influence of matrix elements on landscape connectivity was small in comparison to the influence of habitat elements. Empirical mark-release-resight experiments using Trirhabda beetles in experimental landscapes supported the simulation results.

We monitored population density of white-footed mice (Peromyscus leucopus), burdens of immature black-legged ticks (Ixodes scapularis) on mice, and infection prevalence of host-seeking ticks on six forest plots in southeastern New York State from 1995 through 1999. Despite densities of mice that fluctuated two orders of magnitude, average larval and nymphal tick burdens per mouse remained remarkably constant. Spatial variability in mouse density and tick burdens was modest. The total number of larval and nymphal ticks that fed on the mouse population each year depended strongly on population density of mice; a steady increase was observed in both mouse density and total tick meals on mice from 1996 through 1999. The result was a steady increase in the infection prevalence of nymphal and adult ticks with the etiological agent of Lyme disease, Borrelia burgdorferi, over this time. We suggest that fluctuations in population density of mice, combined with possible regulation of tick burdens on mice, may influence risk of human exposure to Lyme disease.

Spatial heterogeneity in predation risk can ameliorate impacts on prey populations, particularly for prey of generalists. Spatially heterogeneous risk implies the existence of refugia, and the spatial scale of those refugia and their persistence over time affect whether prey can avoid predation by aggregating therein. Our objective was to quantify the magnitude, spatial scale, and temporal persistence of heterogeneity in risk of predation by white-footed mice (Peromyscus leucopus), an abundant generalist predator of gypsy moths (Lymantria dispar) and songbirds. We used track plates to measure white-footed mouse activity at .170 trees in each of three forest plots in upstate New York during summers of 2003-2005. We quantified the mean and coefficient of variation of track activity among trees by fitting the beta-binomial distribution to data from each plot and study period. We measured temporal persistence by disattenuated autocorrelation, and spatial scale by fitting exponential variograms. Mice were much less abundant in 2005 than the other two years, leading to lower overall track activity but higher coefficient of variation among trees. Mouse track activity at individual trees was positively autocorrelated between monthly study periods in 2003 and 2004, and even between the two years, whereas temporal autocorrelation in 2005 was much weaker. Track activity showed positive spatial autocorrelation over lag distances from ;30 to .1000 m. These findings indicate that mouse activity, and hence risk to their prey, varies substantially in space at spatial and temporal scales that appear responsive to mouse population dynamics. The spatial scale and temporal persistence of that variation imply that prey may benefit from returning to, or failing to disperse from, refugia.