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From 2009 to 2013, we tested four systemic insecticide formulations and five application methods against the invasive goldspotted oak borer, Agrilus auroguttatus Schaeffer (Coleoptera: Buprestidae), in California. The insecticides were evaluated in three experiments: 1) 2009 remedial applications of emamectin benzoate (steminjection) and imidacloprid (stem-injection and soil-injection); 2) 2009-2012 emamectin benzoate and imidacloprid initially applied at different times during the dormant season with varying injection technologies; and 3) 2013 dinotefuran applied to several tree diameter size classes. Adult leaf-feeding bioassays were used to assess the impact of systemic treatments against A. auroguttatus, whereas enzyme-linked immunosorbent assays determined the quantity of the active ingredient of insecticide residues in foliage. Imidacloprid (experiment 1) persisted at elevated levels in foliage of coast live oak, Quercus agrifolia Neé, for 1.5 yr following stem injections. Stem injections of emamectin benzoate (experiment 2) sometimes significantly decreased survival in adults fed foliage from treated Q. agrifolia, and both the emamectin benzoate and imidacloprid treatments reduced adult feeding in some trials. Imidacloprid residues in Q. agrifolia and California black oak, Quercus kelloggii Newb., foliage remained at elevated levels (>10 µg/g) ~2 yr postapplication. In 2013 (experiment 3), dinotefuran residues were highest in foliage collections 2 wk postapplication and greatest in smaller diameter oaks, but insecticide treatment had no effect on survival or frass production by adults fed foliage from treated trees. Systemic injections of emamectin benzoate and imidacloprid applied during the dormant season to uninfested or lightly infested oaks can reduce adult A. auroguttatus survival and maturation feeding. [ABSTRACT FROM AUTHOR]

The goldspotted oak borer, Agrilus auroguttatus Schaeffer (Coleoptera: Buprestidae), was linked in 2008 to ongoing tree mortality in oak woodlands of southern California. Mortality of coast live oak, Quercus agrifolia Née, and California black oak, Q. kelloggii Newb., continues as this exotic phloem borer spreads in southern California. Management options are needed to preserve high-value oaks and maintain management objectives. From 2009 to 2012, we tested four contact insecticide formulations in four experiments against A. auroguttatus in California. The impact of contact insecticides was evaluated ~<1, 8, and 12mo postapplication against A. auroguttatus adults in no-choice leaf-feeding or walking bioassays. At<1mo postapplication, bifenthrin, carbaryl, lambda-cyhalothrin, and permethrin all reduced adult survival and feeding in leaf-feeding and walking bioassays. At 8mo postapplication, only bifenthrin reduced adult feeding, but had no effect on survivorship. At 12mo postapplication, adult A. auroguttatus survived fewer days and fed less in leaf-feeding bioassays with bifenthrin, carbaryl, and permerthin. These results support the annual application of contact insecticides prior to A. auroguttatus' flight period to reduce adult leaf maturation feeding and activity on the bark surface (e.g., oviposition), but additional studies are needed to show these contact treatments can prevent tree mortality from this invasive species. [ABSTRACT FROM AUTHOR]

The goldspotted oak borer Agrilus auroguttatus Schaeffer is an invasive pest of three Quercus species in southern California, U.S.A. As a native and potentially indigenous exotic species, its distribution and potential damage is largely unknown in Mexico., We used the maximum entropy algorithm to determine the bioclimatic variables that may explain the distribution of A. auroguttatus, as well as its interaction with the distribution of known hosts in Mexico., Our model calculated high suitability for A. auroguttatus in the biogeographical provinces of California, the northern and southern areas of Sierra Madre Occidental and the northwestern area of the Mexican Plateau; moderate suitability was projected in the Baja California, Sonora and Sierra Madre Occidental provinces. Potential distribution of A. auroguttatus was overlapping with native ranges of Quercus agrifolia, Quercus emoryi Torrey and Quercus hypoleucoides A. Camus. Precipitation of the coldest quarter (23.6%), isothermality (23.5%), precipitation seasonality (17.3%) and mean temperature of the coldest quarter (11.2%) contributed most to explaining its distribution in Mexico., The geographical interaction (i.e. the likelihood that the habitat would be suitable for coexistence) of A. auroguttatus with its hosts in Mexico was projected in the California province (46 382.60 km2, probably as an exotic species) and the northwestern areas of Mexican Plateau and Sierra Madre Occidental provinces (74 013.45 km2, probably as native)., Determining the areas of environmental suitability for A. auroguttatus and its host distribution can focus ground surveys, contribute to management efforts and assist in the development of risk assessments for Mexico. [ABSTRACT FROM AUTHOR]

BACKGROUND The invasive goldspotted oak borer, Agrilus auroguttatus, is threatening the health and survival of oak trees in San Diego County, California. From two sites in the core area of the infestation, we report a 2.5 year investigation of the impact of A. auroguttatus on coast live oak, Quercus agrifolia, before and after treatment with two systemic insecticides, emamectin benzoate ( EB) and imidacloprid ( IC). RESULTS None of the 446 survey trees died during the study. The crown dieback rating of most trees at both study sites remained unchanged, regardless of insecticide treatment. A higher cumulative increase in the number of A. auroguttatus emergence holes was observed on trees that were previously infested and on trees with larger diameters. Over the 2.5 year period, the new infestation rates of initially uninfested trees across the untreated and treated groups were 50% ( EB) and 32% ( IC), and neither EB nor IC treatment affected cumulative increases in the number of emergence holes. EB-injected trees did not have significant annual increases in the number of A. auroguttatus emergence holes at either 1.5 or 2.5 years compared with that at 0.5 years, whereas untreated trees had significant annual increases. Although IC-injected trees had a significantly greater annual increment in the number of emergence holes than untreated trees during the last year of the study, treated trees had significant reductions in annual increases in emergence holes at both 1.5 and 2.5 years compared with that at 0.5 years. Untreated trees had no significant reduction in the annual increase in emergence holes at 1.5 and 2.5 years. CONCLUSIONS A. auroguttatus preferentially attacked previously infested and larger (diameter at breast height > 15-30 cm) oak trees, but the attacks led to very gradual changes in the health of the trees. Both EB and IC provided minor suppressive effects on A. auroguttatus emergence. Published 2014. This article is a U.S. Government work and is in the public domain in the USA. [ABSTRACT FROM AUTHOR]

Abstract: From 2009–2011, we assessed the impact of the goldspotted oak borer, Agrilus auroguttatus Schaeffer, or its sibling species, Agrilus coxalis Waterhouse, at locations in southern California (denoted infested: ICA and uninfested: UCA), southeastern Arizona (AZ), and southern Mexico (MX). Our surveys examined forest composition of oak woodlands; the degree of injury and proportion of oaks infested with either A. auroguttatus (ICA and AZ) or A. coxalis (MX); and the progression of aerially mapped oak mortality in San Diego Co. (ICA). By most measures of impact that we evaluated, the effect on oaks by the two Agrilus spp. was relatively low in their native regions, but significantly higher by A. auroguttatus at ICA sites. Larger diameter red oak species have been the preferred hosts of A. auroguttatus in AZ and ICA sites, and red oaks greater than approx. 13cm in DBH throughout California are likely at risk of injury from this invasive pest. At sites in AZ there was no evidence of infestation by A. auroguttatus on living or dead white oak species, whereas at ICA sites we recorded a minor amount of infestation by A. auroguttatus on living individuals of a white oak species (Quercus engelmannii Greene), but no mortality. In contrast, a white oak from MX sites (Quercus peduncularis) was more frequently infested by A. coxalis than were indigenous red oaks. Across all ICA sites, A. auroguttatus has infested 61% of the live larger diameter oaks and killed 13% of the oak component of the forest (vs. 4% infested and 2% dead in AZ, respectively). At survey plots near the predicted origin of the outbreak in CA, over 90% of the larger diameter red oaks have been infested. Nearly 90% of the dead oaks surveyed across all ICA sites showed evidence of previous injury symptoms from A. auroguttatus. Aerial oak mortality polygons associated with A. auroguttatus have expanded ∼50km in nine years, but our analysis confirms that the outbreak appears to still be confined to San Diego Co. The distance of oak mortality polygons from the predicted origin of the outbreak explained the most variance in a principal component analysis. The invasive population of A. auroguttatus is a significant conservation and ecological threat to the oak woodlands of California and should be managed accordingly, especially by restricting firewood movement. [Copyright &y& Elsevier]

Two of three species previously classified in Calosota Curtis (Hymenoptera: Eupelmidae) from the Neotropical region are transferred to Eupelminae. Calosota eneubulus (Walker) from Galapagos Islands is transferred to Eupelmus Dalman as E. (Eupelmus) eneubulus (Walker), comb. n., and Calosota silvai (Brethes) from Chile is transferred to Brasema Cameron as Brasema silvai comb. n. Calosota cecidobius (Kieffer) from Argentina is retained in Calosota, with reservation, as an unrecognized species. Th e species of Calosota from the New World excluding South America are revised. Eleven species are recognized, including the seven newly described species Calosota albipalpus sp. n. (Costa Rica, Mexico, USA, Venezuela), Calosota bicolorata sp. n. (USA), Calosota elongata sp. n. (USA), Calosota longivena sp. n. (USA), Calosota panamaensis sp. n. (Panama), Calosota setosa sp. n. (Bahamas, Dominican Republic, USA), and Calosota speculifrons sp. n. (Costa Rica, USA). The 11 regional species and the Palaearctic species Calosota vernalis Curtis are keyed and illustrated. Calosota vernalis is not known to occur in the New World but is included in the key and diagnosed because it has been intercepted in quarantine in Canada. Calosota pseudotsugae Burks is placed in synonymy under Calosota acron (Walker), syn. n., and Calosota kentra Burks, Calosota montana Burks and Calosota septentrionalis Hedqvist are placed in synonymy under Calosota aestivalis Curtis syn. n. Calosota modesta Bolívar y Pieltain is removed from synonymy under Calosota viridis Masi, stat. rev., and C. viridis, Calosota matritensis Bolívar y Pieltain, and Calosota coerulea Nikol'skaya are placed in synonymy under Calosota metallica (Gahan), syn. n. Calosota grylli Erdös is confirmed as a separate species from C. metallica based on features of both sexes. It is suggested that Calosota ariasi Bolívar y Pieltain may be a synonym of C. aestivalis, Calosota bolivari Askew may be a synonym of Calosota agrili Nikol'skaya, Calosota dusmeti Bolívar y Pieltain may be a synonym of Calosota violascens Masi, and Calosota lixobia Erdös likely is not a junior synonym of Calosota obscura Ruschka, but formal nomenclatural changes are not proposed prior to a comprehensive Palaearctic revision. Previous interpretation of the mesoscutum in Calosota and Balcha Walker is also modified to include the presence of anteroadmedian lines in addition to notauli and parapsidal lines. [ABSTRACT FROM AUTHOR]

This pest survey card was prepared in the context of the EFSA mandate on plant pest surveillance (M‐2017‐0137), at the request of the European Commission. The purpose of the document is to assist the Member States to plan annual survey activities of quarantine organisms using a statistically sound and risk‐based pest survey approach, in line with current international standards. The data requirements for such an activity include the pest distribution, its host range, its biology and risk factors, as well as available detection and identification methods. This document is part of a toolkit that consists of pest‐specific documents, such as the pest survey cards, and generic documents relevant for all pests to be surveyed, including the general survey guidelines and statistical software such as RiBESS+. [ABSTRACT FROM AUTHOR]