Skip to main content
eScholarship
Open Access Publications from the University of California

Scholarly Works (3 results)

  • Thesis
  • Peer Reviewed
UC Berkeley Electronic Theses and Dissertations (2011)

Cydia Hübner 1825 is a genus of moths in the family Tortricidae with 231 named species and subspecies and is distributed on all continents except Antarctica. As larvae, many species feed within reproductive structures, such as fruits, seeds, and flowers, under bark, or within fleshy stems of at least 65 host-plant species including angiosperms and conifers. Many species, including codling moth, pea moth, spruce seed moth, pine seedworms, filbertworm, and hickory shuckworm are considered pests of agriculture and forestry. As a result, the biology, natural enemies, and pheromones of several species have been well-studied.

The nomenclature and classification of Cydia has also been well-studied but is less resolved. Nineteen different genus names have been proposed for species in this genus, with Laspeyresia Hübner, and Carpocapsa Treitschke being in common usage until relatively recently. Following the rules governing the International Code of Zoological Nomenclature, Cydia is the valid genus name for all species congeneric with the codling moth, Cydia pomonella (Linnaeus), the type species of the genus. The relationship of Cydia to other genera in the tribe Grapholitini is a topic of continued debate. Some authors have suggested that the tribe is an evolutionary grade while others have presented evidence that Grapholitini is a monophyletic clade. Although some secondary sexual characters have been proposed, the genus Cydia can claim no synapomorphies that can be found in all Cydia species. To better understand the systematics and evolution of this group more detailed morphological, molecular, and ecological data are needed for non-pest species.

At least 21 endemic species of Cydia are known from the Hawaiian Islands. Males of most species have a ventral pouch below the cubital vein of the hindwings similar to C. latiferreana (Walsingham), C. maackiana (Danilevsky), and several other Cydia species to a lesser extent, although this feature appears to have arisen independently in the Hawaiian group. Larvae, where known, feed on endemic plants in the family Fabaceae. Identification of species is made difficult by extreme polymorphism of wing patterns for some widespread species and a general reduction of morphological features in the genitalia of male moths, while some features of female genitalia, particularly the antrum and lamella postvaginalis, have diagnostic value. Eight new species of Hawaiian Cydia are described (C. mauiensis n.sp., C. velocilimitata n.sp., C. haleakalaensis n.sp., C. makai n.sp., C. koaiae n.sp., C. hawaiiensis n.sp., C. acaciavora n.sp., and C. anomalosa n.sp.) based on wing patterns and features of male and female genitalia. The thirteen previously known species are redescribed because original descriptions were inconsistent among authors and based solely on wing patterns. Distributions, host-plant affinities, and natural enemies for each species are discussed.

A molecular phylogeny of 66 specimens representing 14 Hawaiian Cydia species plus 20 outgroup species was constructed using nuclear and mitochondrial DNA to assess the relative importance of host-plant affinities and geographic isolation in their diversification. Hawaiian Cydia is monophyletic and nested well-within the genus. They appear to have arrived in the Hawaiian Islands after the rise of Maui based on the basal position of several Maui and Hawaii Island species throughout the phylogeny. The earliest diverging species feed on Canavalia and dispersed across the high islands. Subsequent shifts to feeding on Sophora chrysophylla then Acacia koa were followed by speciation and the filling of these niches across the islands. The origin of Hawaiian Cydia remains obscure, but appears to be a separate colonization of remote Oceania from Cydia pseusomalesana Clarke in French Polynesia.

It is likely that several more species of Hawaiian Cydia await discovery while several others probably have gone extinct in the 100 years since they were first collected. A broader survey of outgroup taxa from Asia and the Americas, and more informative genes in a molecular phylogeny may help resolve the origins of Hawaiian Cydia.

    Cover page: The Systematics, Evolution, and Ecology of Hawaiian Cydia (Lepidoptera: Tortricidae)
    • Article
    • Peer Reviewed
    UC Berkeley Previously Published Works (2015)
    The recently completed Odonata database for California consists of specimen records from the major entomology collections of the state, large Odonata collections outside of the state, previous literature, historical and recent field surveys, and from enthusiast group observations. The database includes 32,025 total records and 19,000 unique records for 106 species of dragonflies and damselflies, with records spanning 1879-2013. Records have been geographically referenced using the point-radius method to assign coordinates and an uncertainty radius to specimen locations. In addition to describing techniques used in data acquisition, georeferencing, and quality control, we present assessments of the temporal, spatial, and taxonomic distribution of records. We use this information to identify biases in the data, and to determine changes in species prevalence, latitudinal ranges, and elevation ranges when comparing records before 1976 and after 1979. The average latitude of where records occurred increased by 78 km over these time periods. While average elevation did not change significantly, the average minimum elevation across species declined by 108 m. Odonata distribution may be generally shifting northwards as temperature warms and to lower minimum elevations in response to increased summer water availability in low-elevation agricultural regions. The unexpected decline in elevation may also be partially the result of bias in recent collections towards centers of human population, which tend to occur at lower elevations. This study emphasizes the need to address temporal, spatial, and taxonomic biases in museum and observational records in order to produce reliable conclusions from such data.
      Cover page: California dragonfly and damselfly (Odonata) database: temporal and spatial distribution of species records collected over the past century
      • Article
      • Peer Reviewed
      UC Berkeley Previously Published Works (2017)
      The emergence rate of new plant diseases is increasing due to novel introductions, climate change, and changes in vector populations, posing risks to agricultural sustainability. Assessing and managing future disease risks depends on understanding the causes of contemporary and historical emergence events. Since the mid-1990s, potato growers in the western United States, Mexico, and Central America have experienced severe yield loss from Zebra Chip disease and have responded by increasing insecticide use to suppress populations of the insect vector, the potato psyllid, Bactericera cockerelli (Hemiptera: Triozidae). Despite the severe nature of Zebra Chip outbreaks, the causes of emergence remain unknown. We tested the hypotheses that (1) B. cockerelli occupancy has increased over the last century in California and (2) such increases are related to climate change, specifically warmer winters. We compiled a data set of 87,000 museum specimen occurrence records across the order Hemiptera collected between 1900 and 2014. We then analyzed changes in B. cockerelli distribution using a hierarchical occupancy model using changes in background species lists to correct for collecting effort. We found evidence that B. cockerelli occupancy has increased over the last century. However, these changes appear to be unrelated to climate changes, at least at the scale of our analysis. To the extent that species occupancy is related to abundance, our analysis provides the first quantitative support for the hypothesis that B. cockerelli population abundance has increased, but further work is needed to link B. cockerelli population dynamics to Zebra Chip epidemics. Finally, we demonstrate how this historical macro-ecological approach provides a general framework for comparative risk assessment of future pest and insect vector outbreaks.
        Cover page: Museum specimen data reveal emergence of a plant disease may be linked to increases in the insect vector population.
        Top