Aggregation Behavior of a Willow Flea Beetle, \u3ci\u3eAltica Subplicata\u3c/i\u3e (Coleoptera: Chrysomelidae)

This study examined the aggregation behavior of a specialist insect herbivore, Altica subplicata (Coleoptera: Chrysomelidae), on its host plant, Salix cordata. Mark-recapture experiments were conducted in patches of S. cordata growing along the shores of Lake Huron. Beetles aggregated on individual host plants, but did not aggregate in larger areas containing many host plants. Plants colonized by marked beetles had significantly higher abundances of unmarked beetles than did plants that were not colonized by marked beetles. Experimental manipulations of the number of beetles present on plants showed that colonization rates by marked beetles were higher on plants with conspecifics than on plants which had all beetles removed the previous day. The sex of beetles, however, did not influence colonization behavior; both male and female beetles colonized plants regardless of the sex of beetles already present on plants. These results are discussed with respect to possible explanations for aggregation, and the role of aggregation and movement in influencing insect distributions

Notes on \u3ci\u3eChrysomelobia Labidomerae\u3c/i\u3e (Acari: Heterostigmata: Podapolipidae), Parasites of \u3ci\u3eLabidomera Clivicollis\u3c/i\u3e (Coleoptera: Chrysomelidae) in Michigan and Wisconsin

Chrysomelobia labidomerae Eickwort, ectoparasitic mite of chrysomelid beetles, is reported from 11 Wisconsin counties, from 16 of 82 adult Labidomera clivicollis (Kirby) beetles wild-caught in Wisconsin, and from 27 of 141 presumably wild-caught L. clivicollis beetles from 13 Michigan counties. Wisconsin beetles harboring C. labidomerae were found in dry to wet-mesic, open habitats. A distribution map and comments are presented

Root Weevil (Coleoptera: Curculionidae) and Ground Beetle (Coleoptera: Carabidae) Immigration into Strawberry Plots Protected by Fence or Portable Trench Barriers

Physical exclusion shows some potential as a novel root weevil control strategy, but barriers to root weevil immigration may also exclude beneficial insects, such as ground beetles. A field study was undertaken in 1997 to assess the impact of two physical barriers—portable plastic trenches and aluminum fences with Teflon tape—on root weevil and ground beetle immigration into plots of strawberry, Fragaria x ananassa (Duchesne). Barypeithes pellucidus (Boheman) and Nemocestes incomptus (Horn), each comprised 43% of the root weevils caught at the site. Most (86%) of the ground beetles caught in control plots were longer than 1 cm, the width of the gap in the portable trench top. Trenches excluded 75 and 63% of B. pellucidus and N. incomptus, respectively, without significantly reducing immigration of large (<1 cm) ground beetles. Fences excluded 65, 84, and 99% of B. pellucidus, N. incomptus, and large ground beetles, respectively. Adding diatomaceous earth to trenches did not increase their efficacy, and fences without Teflon tape excluded ground beetles but not root weevils. The reduction in the population of root weevils and other strawberry pests caused by the use of barriers reduced damage to strawberry plant leaves and increased strawberry plant survival relative to unprotected control plots. Advantages and disadvantages of these physical control tools are discussed with a view to creating superior tools for root weevil exclusion, compatible with an integrated pest management approach. Portable trenches may offer a means of selectively excluding root weevils but not ground beetles

\u3ci\u3eLycaeides Melissa Samuelis\u3c/i\u3e (Lepidoptera: Lycaenidae) Response to an Aggregation of \u3ci\u3eLytta Sayi\u3c/i\u3e (Coleoptera: Meloidae) on \u3ci\u3eLupinus Perennis\u3c/i\u3e (Fabaceae

Lycaeides melissa samuelis Nabokov, frequently called the Karner blue butterfly, is a Federally endangered species found in savanna/barren type ecosystems of New England and the Great Lakes region of North America. We observed sporadic and localized feeding aggregations of Lytta sayi LeConte (Coleoptera: Meloidae) on Lupinus perennis L. (Fabaceae) occupied by L. m. samuelis during the summers of 2000-2004, in Eau Claire County, Wisconsin. In 2004, we quantified the phenology and behavior of an aggregation (\u3e 900 beetles) within a 1,020 m2 stand of lupine and measured its effect upon adult L. m. samuelis behavior. The L. sayi aggregation formed and dispersed within 11 days with three beetles observed on day one and a maximum of 951 beetles on day seven. By the eighth day of the aggregation, the beetles had consumed 100% of the lupine flowers, 2% of lupine seeds and no lupine leaves. In comparisons of L. m. samuelis activity before and during the beetle aggregation, L. m. samuelis males spent significantly less time perching on Potentilla simplex Michaux (Rosaceae) and more time flying during the beetle aggregation. L. m. samuelis females spent significantly less time under lupine leaves during the beetle aggregation. Distribution of L. m. samuelis larval feeding damage suggests adult females avoided ovipositing in areas containing large numbers of beetles

Red Flour Beetle Response to Traps with Prior Captures

The red flour beetle (Tribolium castaneum) is a major pest of food facilities such as flour mills and is often monitored using pitfall type traps with a food oil and pheromone attractant. Previous research had indicated that prior captures of beetles could increase beetle behavior captures in a trap. Here we used a more realistic bioassay to evaluate how the number of beetles previously captured include beetle captures in traps. Results showed no significant impact of prior captures on the number of red flour beetles captured in a trap. There were some trends suggested in the results that warrant further study to investigate, perhaps by focusing on individual beetle behavior at traps rather then using groups of beetles

New Reports of Exotic and Native Ambrosia and Bark Beetle Species (Coleoptera: Curculionidae: Scolytinae) From Ohio

In a 2007 survey of ambrosia and bark beetles (Coleoptera: Curculionidae: Scolytinae) along a transect in northeastern Ohio, we collected six exotic and three native species not previously reported from the state. These species include the exotic ambrosia beetles Ambrosiodmus rubricollis (Eichhoff), Dryoxylon onoharaensum (Murayama), Euwallacea validus (Eichhoff), Xyleborus californicus Wood, Xyleborus pelliculosusEichhoff, and Xylosandrus crassiusculus (Motschulsky). The native ambrosia beetle Corthylus columbianus Hopkins, and the native bark beetles Dryocoetes autographus (Ratzeburg) and Hylastes tenuis Eichhoff are also reported from Ohio for the first time. Our study suggests a northward range expansion for five of the six exotic species including, X. crassiusculus, which is an important pest of nursery and orchard crops in the southeastern United States

Curculionidae and Chrysomelidae Found in Aquatic Habitats in Wisconsin

(excerpt) We became interested in aquatic weevils (Curculionidae) and leaf beetles (Chryso- melidae) during the Aquatic Entomology Course at the University of Wisconsin, in the spring of 1971. Many collections, taken from a variety of aquatic habitats in Wisconsin, contained weevils and leaf beetles. Most of the species were not fully treated in the keys found in aquatic entomology texts. We thought it would be useful to compile keys from the literature and present what is known of the distribution of these insects in Wisconsin. Nine species of weevils have been found in aquatic habitats in Wisconsin, representing seven genera, all belonging to the subtribe Hydronomi, and twenty-five species of leaf beetles, representing five genera in three subfamilies

Sex-Related Color Patterns in Elytral Vittae of \u3ci\u3eDiabrotica Virgifera Virgifera\u3c/i\u3e (Coleoptera: Chrysomelidae)

We evaluated the color patterns of elytral vittae by sex in adults of Diabrotica virgifera virgifera leConte. Our study examined \u3e1000 beetles taken from a field population, a laboratory colony, and a reference collection containing 712 specimens from 15 of the United States and from the province of Ontario, Canada. The humeral and sutural vittae of each beetle\u27s elytra were classified as being separate, partially confluent, or totally confluent with each other. The distribution of these elytral patterns was not independent of sex. Males tended to have confluent or partially confluent vittae, whereas females largely had separate vittae. Nonetheless, all three patterns of elytral vittae were found in both sexes of D. v. virgifera, and many beetles of each sex had partially confluent vittae. This data shows that sexing D. v. virgifera beetles by simple examination of elytral vittae alone is unreliable

Evaluation of semiochemical based push-pull strategy for population suppression of ambrosia beetle vectors of laurel wilt disease in avocado.

Ambrosia beetles (Coleoptera: Curculionidae: Scolytinae and Platypodinae) bore into tree xylem to complete their life cycle, feeding on symbiotic fungi. Ambrosia beetles are a threat to avocado where they have been found to vector a symbiotic fungus, Raffaelea lauricola, the causal agent of the laurel wilt disease. We assessed the repellency of methyl salicylate and verbenone to two putative laurel wilt vectors in avocado, Xyleborus volvulus (Fabricius) and Xyleborus bispinatus (Eichhoff), under laboratory conditions. Then, we tested the same two chemicals released from SPLAT flowable matrix with and without low-dose ethanol dispensers for manipulation of ambrosia beetle populations occurring in commercial avocado. The potential active space of repellents was assessed by quantifying beetle catch on traps placed 'close' (~5-10 cm) and 'far' (~1-1.5 m) away from repellent dispensers. Ambrosia beetles collected on traps associated with all in-field treatments were identified to species to assess beetle diversity and community variation. Xyleborus volvulus was not repelled by methyl salicylate (MeSA) or verbenone in laboratory assays, while X. bispinatus was repelled by MeSA but not verbenone. Ambrosia beetle trap catches were reduced in the field more when plots were treated with verbenone dispensers (SPLAT) co-deployed with low-dose ethanol dispensers than when treated with verbenone alone. Beetle diversity was highest on traps deployed with low-dose ethanol lures. The repellent treatments and ethanol lures significantly altered the species composition of beetles captured in experiment plots. Our results indicate that verbenone co-deployed with ethanol lures holds potential for manipulating ambrosia beetle vectors via push-pull management in avocado. This tactic could discourage immigration and/or population establishment of ambrosia beetles in commercial avocado and function as an additional tool for management programs of laurel wilt