The Asian longhorned beetle, Anoplophora glabripennis (Motschulsky), threatens urban and forest hardwood trees both where introduced and in parts of its native range. Native to Asia, this beetle has hitchhiked several times in infested wood packaging used in international trade, and has established breeding populations in five U.S. states, Canada, and at least 11 countries in Europe. It has a broad host range for a cerambycid that attacks living trees, but in the introduced ranges it prefers maples. Identification, classification, and life history of this insect are reviewed here. Eradication is the goal where it has been introduced, which requires detection of infested trees using several approaches, including ground and tree-climbing surveys. Several agencies and researchers in the United States and Europe are evaluating the use of pheromone- and kairomone-baited traps. Control options beyond cutting down infested trees are limited. To date, the parasitoids and predators of this beetle have broad host ranges and are unlikely to be approved in the United States or Europe. An effective delivery system under development for entomopathogenic fungi appears promising. Systemic insecticides have been widely used in the United States, but the ability of these chemicals to reach lethal doses in the crown of large trees is disputed by some scientists, and the potential nontarget effects, especially on pollinators, raise concerns. The most practical approach for eradicating Asian longhorned beetle is to optimize trapping methods using semiochemicals for early detection to eliminate the insect before it spreads over large areas.
Detecting and controlling the movements of invasive species, such as insect pests, relies upon rapid and accurate species identification in order to initiate containment procedures by the appropriate authorities. Many species in the tussock moth genus Lymantria are significant forestry pests, including the gypsy moth Lymantria dispar L., and consequently have been a focus for the development of molecular diagnostic tools to assist in identifying species and source populations. In this study we expand the taxonomic and geographic coverage of the DNA barcode reference library, and further test the utility of this diagnostic method, both for species/subspecies assignment and for determination of geographic provenance of populations. Cytochrome oxidase I (COI) barcodes were obtained from 518 individuals and 36 species of Lymantria, including sequences assembled and generated from previous studies, vouchered material in public collections, and intercepted specimens obtained from surveillance programs in Canada. A maximum likelihood tree was constructed, revealing high bootstrap support for 90% of species clusters. Bayesian species assignment was also tested, and resulted in correct assignment to species and subspecies in all instances. The performance of barcoding was also compared against the commonly employed NB restriction digest system (also based on COI); while the latter is informative for discriminating gypsy moth subspecies, COI barcode sequences provide greater resolution and generality by encompassing a greater number of haplotypes across all Lymantria species, none shared between species. This study demonstrates the efficacy of DNA barcodes for diagnosing species of Lymantria and reinforces the view that the approach is an under-utilized resource with substantial potential for biosecurity and surveillance. Biomonitoring agencies currently employing the NB restriction digest system would gather more information by transitioning to the use of DNA barcoding, a change which could be made relatively seamlessly as the same gene region underlies both protocols.