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The European winter moth, Operophtera brumata (L.), an invasive forest defoliator, is undergoing a rapid range expansion in northeastern North America. The source of this invasion, and phylogeographic diversity throughout its native range, has not been explored. To do this, we used samples from a pheromone-baited trap survey of O. brumata collected across its native range in Europe, and invasive range in North America. Traps in North America also attract a congeneric species, the Bruce spanworm O. bruceata (Hulst), and the western Bruce spanworm O. b. occidentalis (Hulst). From this sampling, we sequenced two regions of the cytochrome c oxidase subunit I mitochondrial gene; one region corresponds to the DNA ‘barcode’ region, the other is a nonoverlapping section. We used these sequences, in combination with sequence data from a recent survey of the Geometridae in western North America, for phylogenetic and phylogeographic analyses to characterize genetic divergence and variation for O. brumata in North America and Europe, and O. bruceata and O. b. occidentalis in North America. We found O. brumata mtDNA diversity to be dominated by a single widespread, and common haplotype. In contrast, O. bruceata shows high haplotype diversity that is evenly distributed throughout North America. Phylogeographic patterns indicate an introduction of O. brumata in British Columbia likely originated from Germany, and suggest the invasive population in northeastern North America may have its origins in the United Kingdom, and/or Germany. We found uncorrected pairwise sequence divergence between Operophtera species to be ≈7%. O. b. occidentalis is ≈ 5% divergent from O. bruceata, has a restricted range in the Pacific Northwest, and has unique morphological characters. Together these lines of evidence suggest O. b. occidentalis may be deserving of species status. Additionally, a single morphologically unique Operophtera specimen, similar to O. bruceata, was collected in southern Arizona, far outside the known range of O. bruceata. This suggests that North America may contain further, unsampled, Operophtera diversity.

North American tiger beetles (Cicindela spp. L.) have been reared in the laboratory for more than a century, and here we summarize the relevant literature to develop a general rearing protocol. We used this protocol to experimentally overwinter adults in the laboratory and observe variation in oviposition and fecundity among several species. Overwintering experiments, involving five North East North American Cicindela species with spring-fall life histories—Cicindela repanda (Dejean), Cicindela hirticollis (Say), Cicindela purpurea (Olivier), Cicindela scutellaris (Say), and Cicindela tranquebarica (Herbst) —demonstrated that both a long cooldown (20 to 4°C by a degree a day) and a short photoperiod (8:16 [L:D] h) maximized survival and minimized overwintering weight loss, which varied between species and sex. Observations of oviposition, larval abundance and larval development involving five Cicindela species with summer life histories revealed that Cicindela punctulata (Olivier) produced more first-instar larvae than Cicindela abdominalis (F.), Cicindela dorsalis dorsalis (Say), Cicindela puritana (Horn), or Cicindela unipunctata (F.) and that high mortality due to accidental desiccation may be overcome by rearing larvae individually in tubes rather than in bins. We also present a first account of larval rearing of the federally threatened species C. puritana and the northern Martha's Vineyard population of the federally threatened species C. d. dorsalis. Notably, C. d. dorsalis produced fewer larvae than more common species reared in this study. We conclude that rearing large numbers of larvae is feasible with endangered as well as common species and we propose future improvements for rearing as part of conservation efforts.

We used pheromone-baited traps to survey the distribution of winter moth, Operophtera brumata (L.) (Lepidoptera: Geometridae), a new invasive defoliator from Europe in eastern New England. The traps also attracted Bruce spanworm, Operophtera bruceata (Hulst) (Lepidoptera: Geometridae), native to North America. We distinguished between the two species by examining male genitalia and sequencing the mitochondrial cytochrome oxidase subunit 1 (COI) gene, the DNA barcoding region. In 2005, we recovered winter moths at sites stretching from eastern Long Island, southeastern Connecticut, all of Rhode Island, eastern Massachusetts, coastal New Hampshire, and southern coastal Maine. At sites further west and north we captured only Bruce spanworm. In 2006, we confirmed that both winter moth and Bruce spanworm are present in Nova Scotia and in coastal Maine, but only Bruce spanworm was recovered in coastal New Brunswick, Canada; Pennsylvania; Vermont; or Quebec City, Canada. In 2007, we collected Bruce spanworm, but no winter moths, in New Brunswick and the interior areas of Maine, New Hampshire, and New York. Winter moth and Brace spanworm differed in the COI sequence by 7.45% of their nucleotides. The prevalence of intermediate genitalia in the zone of overlap suggested that hybridization between the two species may be occurring. To confirm the presence of hybrids, we sequenced the nuclear gene, glucose-6phosphate dehydrogenase (G6PD). We identified six nucleotides that routinely distinguished winter moth and Bruce spanworm, of which three were always diagnostic. We showed that eggs produced by hybridizing the two species in the laboratory contained copies of both species at these six sites. We found that most of the moths collected in the field with intermediate genitalia had winter moth CO1 and G6PD sequences and thus were not hybrids (or at least F1 hybrids). We found three hybrids out of 158 moths with intermediate genitalia in the region where both species were caught. We conclude that hybrids occur in nature, but are not as common as previously reported. Introgression of genes between the two species may still be significant.

An inexpensive, totally mechanical device was used for monitoring feeding of late-instar larvae of the gypsy moth, Lymantria dispar (L.). A two-lever system transmits feeding motions from a freely suspended piece of artificial diet to a pen nib that writes on a rotating hygrothermograph drum. This device is suitable for monitoring feeding when a fine-grained description of feeding behavior is unnecessary. When larvae were placed into monitors and exposed to 16:8 (L:D) photoperiod, feeding occurred primarily during scotophase. Under continuous scotophase, rhythmicity of feeding was reduced but detectable throughout a 3-day test; under continuous light, feeding became essentially arrhythmic within 24 h. To monitor feeding on foliage, the electronic feeding detector of Kogan (1973) was adapted to the gypsy moth.