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Efficient separation of insects from plant material for quantification and collection is an important component of entomological research. This paper reports on a novel, easily replicable container designed to efficiently collect two different biological control agents dispersing from hemlock (Tsuga spp.) foliage infested with the invasive hemlock woolly adelgid (HWA), Adelges tsugae Annand (Hemiptera: Adelgidae). The container utilizes a simplified Berlese-style funnel design to collect Laricobius spp. (Coleoptera: Derodontidae) larvae dropping from the foliage into a removable bottom jar, a central jar to house the foliage sample, and a removable top jar to collect adult silver flies (Leucopis spp., Diptera: Chamaemyiidae) emerging from puparia on the twigs. The efficacy of two designs (with and without a funnel leading to the top collection jar) was evaluated using western hemlock [Tsuga heterophylla (Raf.) Sarg.] foliage naturally colonized with HWA and the two predator genera. All Laricobius larvae were effectively collected in the bottom jar, and the addition of an inverted funnel leading to the top collection jar increased the proportion of Leucopis flies reaching the target jar from 60% to 94%. This ‘Lari-Leuco’ container is presented as a research and motoring tool to benefit the integrated pest management program for HWA in eastern North America and for potential use in simultaneously separating ascending and descending life stages in other insect-plant or predator-prey systems.

Laricobius nigrinus (Coleoptera: Derodontidae) Fender and Laricobius osakensis (Coleoptera: Derodontidae) Montgomery and Shiyake have been mass produced by Virginia Tech as biological control agents for the hemlock woolly adelgid (HWA), Adelges tsugae (Hemiptera: Adelgidae) Annand, for the past 15 and 9 yr, respectively. Herein, we describe modifications of our rearing procedures, trends and analyses in the overall production of these agents, and the redistribution of these agents for release to local and federal land managers. Based on these data, we have highlighted three major challenges to the rearing program: 1) high mortality during the subterranean portion of its life cycle (averaging 63% annually) reducing beetle production, 2) asynchrony in estivation emergence relative to the availability of their host HWA minimizing food availability, and 3) unintended field collections of Laricobius spp. larvae on HWA provided to lab-reared larvae complicating rearing procedures. We further highlight corresponding avenues of research aimed at addressing each of these challenges to further improve Laricobius spp. production. USDA-Forest ServiceUnited States Department of Agriculture (USDA)United States Forest Service [16-CA-1142004-086]; USDA APHIS PPQ grant [AP19PPQFO000C566] We would like to thank Ryan Mays for his dedication in supplying Laricobius spp. colonies with fresh host material and all the technicians, laboratory assistants, and graduate students who have played a major role in the production of Laricobius spp. agents for field release and experimentation. We would also like to thank Shiyake Shigehiko with the Natural History Museum in Osaka, Japan as our overseas collaborator and all the State and Federal collaborators who have received and released Laricobius agents of the over the past decade and half. We would also like to thank Dr. Albert Mayfield for his review and suggestions prior to submission. This research was supported by the USDA-Forest Service Cooperative agreement 16-CA-1142004-086 and USDA APHIS PPQ grant AP19PPQFO000C566.

The hemlock woolly adelgid (Hemiptera: Adelgidae Adelges tsugae Annand) poses a serious threat to hemlocks in eastern North America, and ongoing research is focused on the identification and development of biological controls to protect and manage hemlock resources. Three predators native to the Pacific Northwest of North America that have been the focus of much research are Leucopis argenticollis (Zetterstedt), Leucopis piniperda (Malloch) (Diptera: Chamaemyiidae), and Laricobius nigrinus (Fender) (Coleoptera: Derodontidae). This study addresses the knowledge gap of adult Leucopis spp. emergence patterns, with comparisons to the timing of larval La. nigrinus drop for pupation. Adult Leucopis spp. emergence was observed in the lab from field-collected, adelgid-infested foliage from Washington state in 2019 and 2020. Adult Leucopis spp. were collected daily as they emerged from foliage collections and identified to species using morphological features; a subset was validated using DNA barcoding. Accumulated heating degree days were calculated to compare a standardized emergence timing across collections made at different locations and temperature regimes. The abundance of the two Leucopis spp. and of the combined Leucopis spp. and La. nigrinus varied among sites and years, and no species was consistently more abundant than the other. Evaluations of seasonal emergence trends of the three species determine the predator complex behaves in a temporally stratified and predictable way. Emergence of adult Le. argenticollis was observed first, followed by La. nigrinus larval drop, with Le. piniperda emerging at the end of larval drop, and finally a second emergence of Le. argenticollis.

Hemlock woolly adelgid (HWA), Adelges tsugae Annand (Hemiptera: Adelgidae), has devastated eastern hemlock (Tsuga canadensis [L.] Carriere) in a major portion of its native range in eastern North America. Population dynamics of HWA in the absence of predators have been studied for decades. After many years and much effort directed towards rearing and releasing biological control agents to manage HWA, one of these agents, Laricobius nigrinus Fender (Coleoptera: Derodontidae), is now successfully established at significant densities at sites from the southern to the mid-Atlantic states of the eastern U.S. However, high densities of HWA still persist at many locations throughout the region and spread of HWA and associated damage to hemlock continues. Population models for HWA have suggested that even upwards of 90% predation on eggs laid by the overwintering sistens generation will have minimal effect in reducing the population densities of HWA, if HWA are at high density. In this study, we tested the ability of L. nigrinus to reduce HWA densities, and experimentally tested these model predictions to better understand what impact, if any, L. nigrinus has on HWA densities. By using predator exclusion cages at field sites with well-established populations of L. nigrinus, we were able to record HWA densities, fecundity, overwintering mortality, and predation by L. nigrinus, as well as the proportion of branch tips producing new growth on study trees. Using our field-collected data, we refitted the model in ways that allowed us to predict what population densities we could expect for the following summertime progrediens generation given previous HWA density and levels of L. nigrinus. In both years, we found that despite high rates (greater than 80% ovisac predation) of predation by L. nigrinus on uncaged branches compared to caged branches, there were no significant differences in subsequent densities of the HWA spring generation between caged and uncaged treatments, as predicted by our model. In 2018, our field-collected densities of the summer progrediens generation were lower than what was predicted by the model in both predator exclusion treatments, possibly due to the model not incorporating tree health and climatic factors. Simulation models of pest insect populations based on field-collected data such as fecundity, density, overwintering mortality, and predation, could prove to be important in informing researchers and managers about the role of the biological control agent in the population dynamics of the target host. USDA Forest Service, USA [14-CA-11420004-181] This work was funded by a cooperative agreement with the USDA Forest Service, USA (No. 14-CA-11420004-181). We thank R., Reardon, N. Schneeburger, R. Rhea of the Forest Service for arranging and administrating our funding, M. Meyer for helping us find field sites in NJ and R. Mays, A. Dechaine (Virginia Tech) and B. Mudder (USDA Forest Service) for helping collect samples from the field. We thank A. Roehrig, A. Langevin for processing samples. We thank H. Broadley, J. Anderson, and B. Padilla for help with statistical analysis and graphics. We thank J. Chandler, R. Van Driesche, and D. Orwig for reviewing earlier drafts of this MS. Public domain – authored by a U.S. government employee

The pine bark adelgid, Pineus strobi (Hartig) (Hemiptera: Adelgidae), is an herbivore native to eastern North America that specialises on eastern white pine, Pinus strobus Linnaeus (Pinaceae). Little is known about P. strobi, especially in its southern range in the Appalachian Mountains, United States of America, and the composition of its predator complex has not yet been documented in this region. The current study identifies arthropod predators associated with P. strobi in Appalachian forests of Virginia based on a two-year survey. Predators were identified using morphology and DNA barcoding. Predator species include: Laricobius rubidus LeConte (Coleoptera: Derodontidae), Leucopis piniperda Malloch (Diptera: Chamaemyiidae), and Leucopis argenticollis Zetterstedt (Diptera: Chamaemyiidae), that are known adelgid specialists. Also found were predators from the families Cecidomyiidae (Diptera), Coccinellidae (Coleoptera), Chrysopidae (Neuroptera), Hemerobiidae (Neuroptera), and Syrphidae (Diptera). The Cecidomyiidae were especially diverse, with 14 different species inferred from their DNA barcodes. Knowledge of this predator complex is particularly valuable for anticipation and detection of potential interactions between native predator species and those that are being considered for the introduction for biological control of invasive adelgid pests within the southern Appalachian ecosystem.

To determine if key attributes for a successful biological control agent are possessed by the predator, Laricobius nigrinus Fender, field studies were conducted in its native range of Seattle, WA. The relationship between adult and immature L. nigrinus abundance to different densities of its prey, Adelges tsugae Annand, were determined. In a second study, predator and prey densities, and survivorship of each sistens A. tsugae stage were determined to gauge the impact of predation. The predator strongly aggregated and increased its reproduction when prey density increased, the two mechanisms of a numerical response. Immature predator-prey ratios were high and average prey density was low in comparison with invaded areas of the eastern United States. Survivorship of aestivating first-instar sistens A. tsugae was low and survivorship of each instar (second, third, and fourth) and adults was high and increased with each stage. When pooled, however, the survivorship of sistens second instar-ovisac stages was low primarily owing to L. nigrinus larval consumption of ovisacs. In its native range, L. nigrinus has key attributes of a successful biological control agent, such as a strong numerical response, high predator-prey ratios, and an important larval impact on A. tsugae populations. Demographic data could serve as important benchmarks for future studies to determine if L. nigrinus and other predators can regulate densities of A. tsugae below eastern hemlock's physiological damage threshold in the eastern United States.

Hemlock woolly adelgid (HWA), Adelges tsugae Annand, is a highly destructive non-native pest lethal to eastern hemlock, Tsuga canadensis (L.) Carrière, and Carolina hemlock, T. caroliniana Engelmann. Fifty years following the first observation of HWA in eastern North America, a predatory beetle, Laricobius nigrinus Fender, was evaluated, approved, and released as a biological control agent. Efforts were made to mass rear L. nigrinus with the goal of redistributing the beetles on public lands, typically in forest ecosystems, as a secondary option to silvicultural and chemical controls. The majority of L. nigrinus releases has occurred on public lands. Herein, we report the observation of L. nigrinus within the urban environment outside of known release locations. Two towns, Blacksburg and Radford, were divided into 0.40 km2 grids. A total of 27 and 19 grids were randomly selected from each town, respectively. Hemlocks were present in 44 and 42% of the grids surveyed in Blacksburg and Radford, respectively. In Blacksburg and Radford, 86 and 100% of the grids with hemlocks were infested with HWA, and of those infested hemlocks, Laricobius spp. was present in 100 and 75% of grids, respectively. A total of 154 Laricobius spp. (98% L. nigrinus and 2% Laricobius rubidus) adults were collected between each town. While it is unclear the level of control L. nigrinus has on reducing HWA's impact, the establishment of this biological control agent in the urban environment is an additional level of predation, that would otherwise not be present, for homeowners with HWA-infested trees.

The hemlock woolly adelgid (Hemiptera: Adelgidae: Adelges tsugae Annand) is an invasive insect, introduced from Japan to eastern North America, where it causes decline and death of hemlock trees. There is a closely related lineage of A. tsugae native to western North America. To inform classical biological control of A. tsugae in the eastern USA, the density and phenology of three native western adelgid specialist predators, Leucopis argenticollis (Zetterstedt), Le. piniperda (Malloch) (Diptera: Chamaemyiidae), and Laricobius nigrinus Fender (Coleoptera: Derodontidae), were quantified in the Pacific Northwest. Infested branches were collected from western hemlock (Pinaceae: Tsuga heterophylla (Raf.) Sarg.) at four sites around the Puget Sound, Washington and three sites in Oregon. Immature Leucopis were identified to species using DNA barcodes. Leucopis argenticollis was roughly twice as abundant as Le. piniperda. Laricobius nigrinus larvae were more abundant than the two species of Leucopis during the egg stage of the first adelgid generation, but Leucopis were present as feeding larvae during the second adelgid generation when La. nigrinus was aestivating in the soil, resulting in Leucopis being more abundant than La. nigrinus across the entire sampling period. Adelges tsugae and La. nigrinus densities were not correlated, while A. tsugae and Leucopis spp. densities were positively correlated. Leucopis spp. and La. nigrinus densities were negatively correlated. These results support the complementary use of La. nigrinus and the two Leucopis species for biological control of A. tsugae in the eastern USA, and point to the need for further investigation of spatial and temporal niche partitioning among the three predator species.

Hemlock woolly adelgid (HWA), Adelges tsugae Annand (Hemiptera: Adelgidae), is an invasive pest causing significant mortality to eastern and Carolina hemlock in eastern North America. Since 2003, management of HWA has included targeted release of the HWA predator Laricobius nigrinus Fender (Coleoptera: Derodontidae), native to western North America. Establishment of L. nigrinus at release sites is well documented, but investigations of its impact on HWA populations have been limited. A four-year (2014-2018), two-phase study using predator exclusion cages to assess the impact of L. nigrinus on HWA was conducted at nine previous release sites in the eastern United States. Significantly more HWA sistens ovisacs were disturbed on no-cage and open-cage branches than on caged branches where predators were excluded. Mean disturbance levels on cage, no-cage and open-cage branches was 8, 38, and 27 percent, respectively. Seven of nine sites had a mean HWA ovisac disturbance greater than 50% for at least one year. Winter temperatures were also a significant factor in overall mortality of the sistens generation with a mean of 46% on study branches. Six of nine sites had a mean overall mortality (winter mortality and predation) greater than 80% for at least one year. Larvae of Laricobius spp. were recovered at all sites during this study. Sequencing of the COI gene from recoveries in Phase One (2015 and 2016) indicated that 88% were L. nigrinus and 12% were L. rubidus LeConte. Microsatellite analysis performed during Phase Two (2017 and 2018) indicated that approximately 97% of larval recoveries were L. nigrinus, 2% were hybrids of L. nigrinus and L. rubidus, and 1% were L. rubidus. Results of this study suggest that L. nigrinus can significantly impact the HWA sistens generation ovisacs and continued investment in the use of this species as a biological control is recommended. USDA Forest Service cooperative agreementUnited States Department of Agriculture (USDA)United States Forest Service [14-CA-11420004-028] We gratefully acknowledge the assistance of Dr. Thomas Kuhar and Dr. Douglas Pfieffer (Virginia Tech) for review of this project, as well as Dr. Carlyle Brewster (Virginia Tech) for assistance with data analysis. We thank Dr. Nathan Havill (USDA Forest Service), Kari Stanley (Virginia Tech), and Melissa Fischer (Washington State Department of Natural Resources) for assistance with molecular protocols, as well as Mark Mayer (New Jersey Department of Agriculture), Scott Passwaters (James River State Park), Biff Thompson (Maryland Department of Agriculture), Jesse Webster (Great Smoky Mountains National Park), and the staff at Blackberry Farm (Tennessee) for site assistance. Thank you to Arthur Morgan School, Celo Community, and the Chattahoochee National Forest for permission to use sites in NC and GA. We are grateful to Natalie Morris, Kara Jeffries, Andy Dechaine, Ryan Mays, Ashley Toland, and James Wahls (Virginia Tech), Bryan Mudder and Andrew Tait (USDA Forest Service), David Bechtel, Philip Hensley, Elizabeth McCarty, Forest Palmer, Pat Parkman, and David Paulsen (University of Tennessee), and Peter Menzies, Marika Lapham, and Ivy Haas (University of North Carolina Asheville), for laboratory and field assistance. This work was funded under USDA Forest Service cooperative agreement 14-CA-11420004-028. Public domain – authored by a U.S. government employee

The hemlock woolly adelgid (HWA) is an invasive insect species native to Japan causing significant hemlock mortality in the eastern United States. Laricobius spp. have been targeted as biological control agents because they are adelgid specialists. Laricobius osakensis Montgomery and Shiyake is native to the same region of Japan from which the strain of HWA found in the eastern United States originated. Studies in Japan found that it is phenologically synchronous with HWA. Following approval to release L. osakensis from quarantine in 2010, approximately 32,000 were released at a total of 61 sites starting in 2012. In winter of 2014 and 2015, periods of extreme cold temperatures throughout the eastern USA, as well as the polar vortex, resulted in extensive mortality to HWA, which likely delayed the establishment of L. osakensis. The ability of the beetle to survive and establish in the eastern United States is reported here. In the first year of this study (2015&ndash, 2016), limited numbers of L. osakensis were recovered, as HWA populations were still rebounding. In the second year (2016&ndash, 2017), 147 L. osakensis were collected at 5 of 9 sites sampled, coinciding with rebounding HWA populations. Larval recovery was much greater than adult recovery throughout the study. HWA density was directly correlated with warmer plant hardiness zones and recovery of Laricobius beetles was significantly correlated with HWA density. Our results suggest that L. osakensis is successfully establishing at several of the sampled release sites and that the best predictor of its presence at a site is the HWA density.

Biological control of Adelges tsugae (Hemiptera: Adelgidae; Hemlock Woolly Adelgid [HWA]) is an essential component of a management plan for this non-native pest of Tsuga spp. native to eastern N. America. The predatory beetle Laricobius osakensis Montgomery and Shiyake (Coleoptera: Derodontidae) shows potential as a biological control agent because of its coevolved life-cycle with HWA in its native habitat and its voracious appetite for HWA. In the first releases ever made for this species, adult beetles were introduced at 4 sites in the eastern United States with 2 long-term objectives: (1) suppressing HWA populations, and (2) developing field insectaries for re-distribution of predators in the future. Our immediate objectives were to determine the predator's survival and colonization in eastern Tsuga forests following their introduction. In addition, L. osakensis eggs were set out at the 4 release sites. Results from the first year post-release of adult beetles indicated that reproduction occu...

Laricobius nigrinus Fender (Coleoptera: Derodontidae) is a specialist predator of the hemlock woolly adelgid, Adelges tsugae Annand (Hemiptera: Adelgidae), native to the Pacific Northwest. It has been introduced into the eastern United States for biological control of exotic hemlock woolly adelgid populations that threaten native hemlock. The possible role of olfactory cues in host finding by this predator has received little study. We used gas chromatography–electroantennographic detection (GC-EAD) to test adult L. nigrinus olfactory sensitivity to volatiles from foliage of both adelgid-infested and uninfested eastern hemlock [Tsuga canadensis (L.) Carriere] and western hemlock [Tsuga heterophylla (Raf.) Sarg.], and two hemlock woolly adelgid nonhost species (eastern white pine, Pinus strobus L., and western white pine, Pinus monticola Douglas ex D. Don). Adelgid infestation did not alter L. nigrinus EAD response profiles to volatiles from either hemlock species. In total, antennal preparations...

In 2003, Laricobius nigrinus Fender was introduced into the eastern United States as a biological control agent of the hemlock woolly adelgid (Adelges tsugae Annand). Following its release, it was discovered that L. nigrinus was hybridising and producing viable progeny with Laricobius rubidus LeConte, a species native to eastern North America. Recently, Laricobius osakensis Montgomery and Shiyake was imported from Japan into the USA as a potential biological control agent of hemlock woolly adelgid. Hybridisation between L. nigrinus and L. rubidus led to interest in the outcome of interactions between L. osakensis and the other two Laricobius spp. The purpose of this study was to determine if L. osakensis could mate with L. nigrinus, if they could produce hybrid progeny, and whether mating interferes with reproductive output. Laricobius spp. were observed mating directly following emergence and found to be capable of producing sterile eggs in the absence of a mating event. Laboratory and confined field stu...

Summary This study investigated the use of emergence traps to assess densities of Laricobius nigrinus Fender (Coleoptera: Derodontidae), a predator of hemlock woolly adelgid (Hemiptera: Adelgidae), in an area of release and establishment. Results indicate that traps effectively collect emerging adults and allow systematic population estimates of L. nigrinus. The incorporation of this method in future monitoring efforts could enable population estimates across the release range of L. nigrinus, thereby enhancing the evaluation of establishment and long-term persistence of this predator.

An integrated management approach is needed to maintain eastern hemlock (Tsuga canadensis (L.) Carriere) in eastern North America and to minimize tree damage and mortality caused by the invasive hemlock woolly adelgid (Adelges tsugae Annand). This study examined the hypothesis that chemical control with low rates of insecticide and biological control can be combined in the same stand to impact adelgid populations, prolong crown health, and allow predator proliferation. Sixty T. canadensis trees in northern Georgia were individually treated via soil injection with 0%, 10%, or 25% of the label rate of imidacloprid insecticide, and the biological control predator Laricobius nigrinus Fender was released in the stand, two and four years later. By year seven, hemlocks treated with the 25% imidacloprid rate lost their insecticide protection, had significantly better crown health and higher adelgid densities than untreated trees, and supported as many Laricobius predator larvae as untreated trees. In year seven, no residues of imidacloprid were detected in Laricobius larvae feeding on previously-treated hemlocks. Most (77%) of the predators collected on study trees were identified as L. nigrinus, 12% were the native congener Laricobius rubidus LeConte, and 11% were hybrids between the introduced and native species. The hybridization rate remained stable over time. The density of undisturbed A. tsugae ovisacs was twice as high on branches protected from predators as compared with branches exposed to predators. Results suggest that chemical and biological control of A. tsugae can be successfully integrated to help prolong hemlock health, although additional predators may be necessary to protect hemlock trees in the southern Appalachians.

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LOHSE, Die Kafer Mitteleuropas 11, Krefeld.","LOHSE G.A. & W.H. LUCHT (1989): 9. Familie: Hydrophilidae. - In: Lohse G.A. & W.H. Lucht, Die Kafer Mitteleuropas 12 (1. Supplementband), Krefeld.","LUCHT W. (1998): 32.a Familie: Trogossitidae. - In: LUCHT W. & B. KLAUSNITZER, Die Kafer Mitteleuropas 15 (4. Supplementband), Jena.","MACHATSCHKE J.W. (1969): 85. Familie: Scarabaeidae (Blatthornkafer). - In: FREUDE H., HARDE K.W. & G.A. LOHSE, Die Kafer Mitteleuropas 8, Krefeld.","MITTER H. (1981): Zur Verbreitung einiger Arten der Familie Serropalpidae in Oberosterreich (Coleoptera, Serropalpidae). - NachrBl. bayer. Ent. 30: 79-80.","MITTER H. (2000): Die Kaferfauna Oberosterreichs (Coleoptera: Heteromera und Lamellicornia). - Beitr. Naturk. Oberosterreichs 8: 3-192.","MITTER H. (2000): Verbreitung und Biologie der Eucnemidae und Lissomidae (Coleoptera, Elateroidea) in Oberosterreich. - Beitr. Naturk. Oberosterreichs 9: 39-45.","MITTER H. (2001): Die Kaferfauna des Naturschutzgebietes \"Staninger Leiten\" (Oberosterreich, Unteres Ennstal). - Beitr. Naturk. Oberosterreichs 10: 415-437.","MITTER H. (2001): Bestandsanalyse und Okologie der nach FFH-Richtlinie geschutzten Kafer in Oberosterreich (Insecta, Coleoptera). - Beitr. Naturk. Oberosterreichs 10: 439-448.","MITTER H. (2002): Vergleichende Untersuchung der Kaferfauna an drei Halbtrockenrasen im Unteren Steyrtal (Keltenweg, Kreuzberg, Kuhschellenboschung Neuzeug, Oberosterreich). - Beitr. Naturk. Oberosterreichs 11: 5-34.","MITTER H. (2005): Bemerkenswerte Kaferfunde aus Oberosterreich VIII (Insecta: Coleoptera). - Beitr. Naturk. Oberosterreichs 14: 411-433.","MITTER H. (2007): Bemerkenswerte Kaferfunde aus Oberosterreich IX (Insecta: Coleoptera). - Beitr. Naturk. Oberosterreichs 17: 169-194.","MITTER H. (2008): Bemerkenswerte Kaferfunde aus Oberosterreich X (Insecta: Coleoptera). - Beitr. Naturk. Oberosterreichs 18: 297-303.","MITTER H. (2009): Bemerkenswerte Kaferfunde aus Oberosterreich XI (Insecta: Coleoptera). - Beitr. Naturk. Oberosterreichs 19: 339-346.","MITTER H. (2012): Bemerkenswerte Kaferfunde aus Oberosterreich XII (Insecta: Coleoptera). - Beitr. Naturk. Oberosterreichs 22: 69-82.","MITTER H. (2015): Bemerkenswerte Kaferfunde aus Oberosterreich XIII (Insecta: Coleoptera). - Linzer biol. Beitr. 47 (1): 691-706.","MULLER- MOTZFELD G. (Hrsg.) (2004): Bd. 2 Adephaga 1: Carabidae (Laufkafer). - In: FREUDE H., HARDE K.W., LOHSE G.A. & B. KLAUSNITZER, Die Kafer Mitteleuropas 2, 2. Aufl., Heidelberg/Berlin.","REDTENBACHER L. (1874): Fauna Austriaca, 3. Aufl., Wien.","SCHUH R, PLONSKI I.S. et al. (2011): Bemerkenswerte Kaferfunde aus Osterreich (XVIII) (Coleoptera). - Koleopt. Rdsch. 81: 327-332, Wien.","SPORNRAFT K. (1967): 50. Familie: Nitidulidae. - In: FREUDE H., HARDE K.W. & G.A. LOHSE, Die Kafer Mitteleuropas 7, Krefeld.","VOGT H. (1967): 59. Familie: Mycetophagidae. - In: FREUDE H, HARDE K.W. & G.A. LOHSE, Die Kafer Mitteleuropas 7, Krefeld.","VOGT H. (1967): 60. Familie: Colydiidae. - In: FREUDE H., HARDE K.W. & G.A. LOHSE, Die Kafer Mitteleuropas 7, Krefeld.","WITTMER W. (1979): 27. Familie: Cantharidae, pars Malthinini. - In: FREUDE H., HARDE K.W. & G.A. LOHSE, Die Kafer Mitteleuropas 6, Krefeld.","WITZGALL K. (1971): 10. Familie: Histeridae. - In: FREUDE H., HARDE K.W. & G.A. LOHSE, Die Kafer Mitteleuropas 3, Krefeld."]}

Derodontus macularis (FUSS, 1850) M a t e r i a l: Nationalpark Kalkalpen, Wald oberhalb Zaglbauer-Alm, 1150m, 11.11.2015, 4 Ex. leg. E. Weigand. An Baumschwämmen (Ungulina fuliginosa) auf alten Buchen, an den Wurzeln von Tannenstöcken und an verpilztem Holz in Gebirgswäldern, von Oktober bis Dezember und im zeitigen Frühjahr. In Südosteuropa und im südlichen Mitteleuropa verstreut und sehr selten; Allgäu, Tirol, Steiermark, Böhmerwald, Beskiden. E r s t n a c h w e i s f ü r O b e r ö s t e r r e i c h!, Published as part of Mitter, Heinz, 2017, Bemerkenswerte Käferfunde aus Oberösterreich XIV und Anhang weiterer bemerkenswerter Funde aus Österreich (Insecta: Coleoptera), pp. 1489-1504 in Linzer biologische Beiträge 49 (2) on page 1492, DOI: 10.5281/zenodo.5412239

The first fossil tooth-necked fungus beetle, Juropeltastica sinica gen. n. sp. n., is described and illustrated based on a single impression fossil from the Middle Jurassic Daohugou beds (ca. 165 Ma) of northeastern China. i t represents the first definitive fossil be- longing to the extant family Derodontidae. Juropeltastica is placed in Derodontidae based on its overall body shape and size, head with complex systems of tubercles and grooves, pronotum with dentate lateral carinae, open mesocoxal cavities bordered by mesepimeron and metanepisternum, excavate metacoxae, and 5-segmented abdomen. The occurrence of a reliable derodontid fossil from 165 mil- lion years ago places Derodontidae among the small but growing number of beetle families of known Middle Jurassic age, which is important in the dating of phylogenetic trees.

The hemlock woolly adelgid, Adelges tsugae Annand, is an invasive insect that threatens hemlock species in eastern North America. Several species from the genus Laricobius are predators of A. tsugae in its native areas of Asia and the western United States. Two Laricobius species have been released as biological control agents: Laricobius nigrinus Fender, and Laricobius osakensis Montgomery and Shiyake. Laricobius rubidus LeConte is an adelgid predator native to the Eastern United States, where it can feed and complete development on A. tsugae opportunistically. Laboratory assays were conducted to assess the cold hardiness of these three Laricobius species, including two distinct populations of L. osakensis, by measuring the supercooling points of each species from November 2016 through March 2017. This information may be useful for choosing the best-suited biological control agent for a particular region to control A. tsugae. There was a significant difference between the overall mean supercooling point of L. rubidus compared to the other Laricobius spp. There were also significant differences of supercooling points between L. rubidus and both strains of L. osakensis in January, and significant differences between L. rubidus and all other strains in February. L. rubidus appear better adapted to cold extremes in the eastern U.S. than imported Laricobius spp. Published version

A method for determining the sex of live adult Laricobius nigrinus Fender (Coleoptera: Derodontidae) is described. Beetles were briefly chilled and positioned ventral-side-up under a dissecting microscope. Two forceps with blunted ends were used to gently brace the beetle and press on the centre of the abdomen to extrude its terminal segments. Male beetles were distinguished by a sclerotised, reticulate ninth abdominal sternite. In females, the distinct ovipositor (tergite, valvifers (ninth sternite), and laterotergites of the ninth abdominal segment) was visible. The procedure was rapid and harmed only a small number of individuals (fewer than 5%). Resume—Nous decrivons une methode pour determiner le sexe chez des adultes vivants de Laricobius nigrinus Fender (Coleoptera: Derodontidae). Les coleopteres sont brievement refroidis et places sur le dos sous une loupe microscopique. Deux brucelles a bouts emousses permettent de delicatement immobiliser l'insecte et appuyer sur le centre de l'abdomen pour faire sortir les segments terminaux. Les coleopteres mâles se reconnaissent par leur neuvieme sternite abdominal sclerifi ee t reticule. Chez les femelles, l'ovipositeur est bien visible; il se compose du tergite, des valviferes (neuvieme sternite) et des laterotergites du neuvieme segment abdominal. La procedure est rapide et ne blesse qu'un petit nombre d'individus (moins de 5%).

The hemlock woolly adelgid, Adelges tsugae Annand, is a serious, non-native pest of hemlock in eastern North America. Laricobius osakensis Montgomery and Shiyake was identified as a key predator in Japan, where A. tsugae is native. Performance of adult and immature stages of L. osakensis was evaluated in sleeve cages on adelgid infested Tsuga canadensis (L.) Carriere in plant hardiness zones 5b and 6b in the mountains of southwestern Virginia, USA. Adults fed on the adelgid and laid eggs during all biweekly sample periods from December 2010 to May 2011, including winter when the temperature averaged below 0 C. In cages with one adult pair (one male and one female), predation of A. tsugae/predator was 0.3–0.9/day during December and January, increased to 2.5/day in February, and then declined to 0.15/day in early May. The oviposition rate lagged the changes in feeding by 2–4 weeks, increasing from 0.02 eggs/day, from December to mid-January, to a peak of 1.5 eggs/day in early April, then declining to 0.4 eggs/day in late April. Mortality was 20% in cages left undisturbed for two months during the winter; even though temperatures were as low as 18 C (cages examined biweekly had higher mortality, likely due to disturbance). In cages left undisturbed for two months during winter or early spring, 34 and 37 progeny were recovered, respectively. During each bimonthly period, a pair of adults and their progeny consumed 2.5 and 2.4 adult adelgids or ovisacs per day, respectively. Twenty-eight days after eggs were placed in the cages (on 11 March or 27 April 2012), 48% and 95% of the recovered larvae had reached maturity and each larva had destroyed 43 and 39 ovisacs, respectively. This research indicates that L. osakensis may have the potential to be an effective biological control agent of A. tsugae in most of the area where it is a pest in the eastern US.

Laricobius osakensis Montgomery & Shiyake, native to Japan, is being measured as a potential biological control agent of the hemlock woolly adelgid, Adelges tsugae Annand, in the eastern United States. Adelges tsugae, a destructive pest threatening the hemlock ecosystems in the eastern United States, was introduced from Japan. This is the first detailed study of the life history of L. osakensis, A. tsugae, and their interaction in Japan. The seasonal abundance of L. osakensis and A. tsugae was assessed in a field study conducted from December of 2007 to November of 2008 in Hyogo, Nara, and Osaka Prefectures (Japan). The sistentes generation of A. tsugae in Japan matured 2 mo later than that reported in British Columbia, Canada, but 1 and 2 mo earlier than in Virginia and in Connecticut, respectively. Timing of the sexuparae generation occurrence in Japan was similar to that observed in Connecticut and Virginia, but this generation has not been observed in British Columbia. Phenological differences among the various A. tsugae population in the eastern U.S. states and Japan can be explained by temperature differences at the locations. Aestival diapause of the predator L. osakensis coincided with diapausing first-instar A. tsugae sistentes. The start of L. osakensis adult activity, oviposition, and larval development was synchronized closely with sistentes development resumption, sistentes adults close to oviposition, and sistentes adults with eggs, respectively. These results indicate good synchrony between L. osakensis and suitable prey stages of A. tsugae in the native habitat of both species.

From 2010 through 2013, adult emergence and seasonality of Laricobius nigrinus Fender, an introduced predatory species native to western North America, as well as hybridization with the native species Laricobius rubidus (LeConte), were evaluated using emergence traps and beat-sheet sampling in areas of previous release against hemlock woolly adelgid, Adelges tsugae Annand. The shortest emergence period of adult L. nigrinus was 7 wk beginning 22 October 2010, and the longest emergence was 15 wk beginning 17 October 2012. Native L. rubidus also were collected from emergence traps placed on the ground surface and beat-sheet samples all 3 yr, with emergence of L. rubidus initiating later than L. nigrinus each season. Seasonality of both Laricobius species was similar across a 44-mo study period. Adult L. nigrinus were present from October through April, and larvae of Laricobius spp. were collected from February to May. The average number of L. nigrinus from emergence traps was significantly greater than the average number of beetles collected from beat-sheet samples in 2010, while the converse was observed during 2012. Hybridization between L. nigrinus and L. rubidus was documented from 10.75% of specimens collected during 2010 and 2011, indicating periodic interbreeding between the introduced and native species. These findings suggest emergence trapping may be a useful method to assess establishment, population densities, and seasonality of Laricobius species in areas of release to enhance their use in management of A. tsuage.

Hybridization between introduced biological control agents and native species has the potential to impact native biodiversity and pest control efforts. This study reports progress towards predicting the outcome of hybridization between two beetle species, the introduced Laricobius nigrinus Fender and the native L. rubidus LeConte. L. nigrinus is a predator from western North America introduced to hemlock stands in the eastern United States as a biological control of the hemlock woolly adelgid [Adelges tsugae Annand (Hemiptera: Adelgidae)]. Laricobius rubidus is a closely related eastern species that also feeds on A. tsugae but prefers pine adelgids (Pineus strobi Hartig) on white pine (Pinus strobus L.). Six microsatellite markers plus mitochondrial COI haplotypes were used to examine genetic structure of these two Laricobius species across North America. In their native ranges, major geographic features have impacted gene flow: the intermountain region in the West, and the Appalachian Mountains in the East. Analysis of 1229 individuals from adelgid-infested hemlock trees in release sites in the eastern United States found widespread hybridization with asymmetrical introgression towards L. nigrinus on hemlock. The ultimate outcome of hybridization could therefore be a complex mosaic of genetic introgression across the landscape, depending on the distribution of hemlock and pine. This study confirms the importance of evaluating the potential for introduced biological control agents to hybridize with their native relatives. This system also provides an excellent opportunity to improve our understanding of emerging hybrid zones by tracking its progress over time.

Predation, egg production, and survivorship of Laricobius nigrinus Fender, L. rubidus LeConte, and L. osakensis Montgomery and Shiyaki, predators of hemlock woolly adelgid, Adelges tsugae Annand, were investigated in the laboratory and in the field. In individual assays in the laboratory, L. rubidus oviposited fewer eggs than either L. nigrinus or L. osakensis. In assays containing congeneric or conspecific groups of adult Laricobius, L. osakensis preyed upon the greatest number of ovisacs. The number of ovisacs preyed upon was not different between treatments with all three species and those with only L. osakensis or L. nigrinus. Adult predators fed on few predator eggs and when they did no species preference was observed. The numbers of A. tsugae ovisacs fed upon did not differ significantly by groups of congeneric or conspecific Laricobius larvae. Laricobius adults and larvae had high survival rates throughout all experiments. In the field, L. nigrinus and L. rubidus were enclosed in sleeve cages with both high (>120 ovisacs) and low (

1 Post-release distributions of Laricobius nigrinus, a biological control predator of hemlock woolly adelgid Adelges tsugae Annand, were evaluated at eight hemlock forests in the eastern U.S.A. 2 Vertical dispersal of F1 and F2L. nigrinus were assessed from within three crown strata ( 15 m) at four release sites. 3 Horizontal distributions of L. nigrinus within the forest surrounding central release areas were observed in two separate studies, which included (i) release and monitor to capture parent and F1 movement by sampling the immature life stages of the offspring, and (ii) assessment of F3 to F6 generations where beetles were previously determined to be established. 4 Laricobius nigrinus, released on lower crown branches, oviposited within the upper crown stratum and were slow to disperse from release trees. Monitoring L. nigrinus only from the lower crown would likely underestimate its presence because 86% of the F2 generation were detected above 15 m. 5 By the fifth generation, the frequency distributions of larvae increased at increasing distance from release areas; larvae were recovered at a maximum distance of approximately 400 m and the spread rate was approximately 39 m/year. 6 Slow dispersal of L. nigrinus and uninterrupted recovery of six generations in the presence of fluctuating prey density support its continued release as part of the A. tsugae biological control programme. These data contribute toward improved release strategies and monitoring for this biological control agent.

Laboratory studies were carried out to determine the functional and numerical responses of the adults and larvae of Laricobius osakensis Montgomery and Shiyake and Laricobius nigrinus Fender to different densities of its prey, Adelges tsugae Annand. Males, females and larvae of both species showed a type II functional response. Overall attack rates and handling times for L. osakensis males and females were comparable. For L. nigrinus males and females, attack rates were similar but handling times differed significantly. Females of both species had the same attack rates and handling times, but L. nigrinus males showed a higher attack rate and longer handling time than L. osakensis males. Males killed significantly more A. tsugae adults than did females for both species, but there were no significant differences between species. The number of eggs laid by the predators (numerical response) as a function of A. tsugae density (d) was modeled by the equations: ne = 2.6691 ln(d) + 3.4135 and ne = 2.3863 ln(d) − 0.5356 for L. osakensis and L. nigrinus, respectively. L. osakensis laid significantly more eggs than L. nigrinus for all prey densities. While L. osakensis preferred to lay the eggs under the A. tsugae adults, most L. nigrinus eggs were in the wool. Attack rates were similar, but L. osakensis larvae handling time was significantly less than that of L. nigrinus larvae. The higher numerical response, combined with the higher functional response of L. osakensis larvae indicates that this species can potentially be more effective than L. nigrinus.

We studied the adult ambulatory response of the predator, Laricobius nigrinus Fender (Coleoptera: Derodontidae), to odors from its prey, Adelges tsugae Annand, the hemlock woolly adelgid, and foliage of hemlock woolly adelgid, host hemlocks (Tsuga spp.), and other conifers. Both the predator and hemlock woolly adelgid are apparently native to western North America, but the predator is being released in the eastern United States, which has different hemlock species, for biological control of a lineage of hemlock woolly adelgid inadvertently introduced from Japan. L. nigrinus responded to odors from hemlock woolly adelgid host trees, but not to odors from hemlock woolly adelgid. L. nigrinus collected from hemlock woolly adelgid-infested western hemlock were more strongly attracted to odors from western hemlock [Tsuga heterophylla (Rafinesque) Sargent] than eastern hemlock [Tsuga canadensis (L.) Carrière] in most trials. Odors from western white pine (Pinus monticola Douglas ex D. Don) and white spruce [Picea glauca (Moench) Voss] were as attractive as western hemlock odors whereas odors from Douglas-fir [Pseudotsuga menziesii variety menziesii (Mirbel)] and ponderosa pine (Pinus ponderosa Douglas ex Lawson) were avoided. L. nigrinus reared on hemlock woolly adelgid-infested eastern hemlock in the laboratory were lethargic and were not attracted to either eastern or western hemlock odors. Predators collected in the field and tested monthly from December to March responded similarly each month, except February, when they flew rather than walked in the olfactometer, suggesting a period of dispersal or mate finding at that time of year. The implications of these results for programs to release L. nigrinus in the eastern United States for control of hemlock woolly adelgid are discussed.

Laricobius nigrinus (Coleoptera: Derodontidae) was first collected near the coastal city of Victoria, British Columbia, Canada for release as a biological control agent to suppress tree-killing densities of hemlock woolly adelgid, Adelges tsugae (Hemiptera: Adelgidae), in the eastern United States. Beetles established in warm areas of the invaded range of A. tsugae, but had a low probability of establishment in cold areas. With the goal of locating beetles with greater cold-tolerance, we collected hundreds of adults in the northern Rocky Mountains. To support planned releases of these inland L. nigrinus, the cold tolerance of field-collected coastal (Seattle, WA) and inland (Coeur d’Alene and Moscow, ID) adults and climate match index scores (CLIMEX v.2) of these collection areas and parts of the eastern United States were compared. We found that individuals of inland L. nigrinus were more cold tolerant than those of coastal L. nigrinus, based on higher survival in a winter field cage study in Massachusetts and a lower supercooling point in a laboratory assay. Inland L. nigrinus also had higher survival than coastal L. nigrinus after an 18 h exposure to sub-zero temperatures in another laboratory assay. Areas of the eastern United States infested with A. tsugae and receiving L. nigrinus releases matched the climate of Seattle and Coeur d’Alene reasonably well, but Coeur d’Alene had higher index values over a considerably larger area than Seattle. Accordingly, inland L. nigrinus appears preferable for release in the colder portions of A. tsugae’s invaded range in the eastern United States.

Molecular diagnostics based on DNA barcodes can be powerful identification tools in the absence of distinctive morphological characters for distinguishing between closely related species. A specific example is distinguishing the endemic species Laricobius rubidus from Laricobius nigrinus, a biological control agent of hemlock woolly adelgid introduced into the eastern United States. This is especially important because their larvae are morphologically similar and are often collected together in stands where pines and hemlock grow together. Diagnostic nucleotide differences to distinguish species were determined using 157 L. nigrinus and 205 L. rubidus cytochrome oxidase I (COI) barcode DNA sequences. Two polymerase chain reaction (PCR) assays were developed: PCR followed by restriction length polymorphism (RFLP) and real-time PCR (qPCR) based on hydrolysis probes. The qPCR assay had limited success when applied to L. nigrinus originating from inland vs. coastal populations in the western United States. PCR–RFLP was successful, regardless of sample origin. These two species-specific assays provide a choice of diagnostic tools to best match the available lab equipment and management objectives for those using L. nigrinus as a biological control agent.

Laricobius osakensis Montgomery and Shiyake sp. nov., collected from Adelges tsugae Annand on hemlock [Tsuga sieboldii Carr. and Tsuga diversifolia (Maxim.) Mast.] in Japan, is described and illustrated. The new species was collected from several localities on Honshu, Shikokou, and Kyushu Islands. The genus has not been reported previously from Japan. Morphological features, a molecular phylogeny, and diagnostic DNA sites are provided to distinguish this new species from previously described species of the genus. Because of plans to release L. osakensis for the biological control of A. tsugae in eastern North America, a key and discussion are provided to differentiate it from the native North American species, Laricobius nigrinus Fender, Laricobius laticollis Fall, and Laricobius rubidus LeConte, and from two previously imported species—Laricobius erichsonii Rosenhauer, which is endemic in Europe, and Laricobius kangdingensis Zilahi-Balogh & Jelinek, which is endemic in China.

Hemlock woolly adelgid, Adelges tsugae Annand (Hemiptera: Adelgidae), is an invasive pest of eastern hemlock (Tsuga canadensis (L.) Carriere) and Carolina hemlock (T. caroliniana Englem.) in eastern United States. Host-range tests for Laricobius osakensis Montgomery and Shiyake (Coleoptera: Derodontidae), imported from Japan, were conducted under quarantine in Blacksburg, VA, to determine the suitability of this predator as a biological control agent of A. tsugae. Host-range testing for L. osakensis, involved no-choice and paired choice feeding, oviposition, and development tests with A. tsugae, three other adelgids, and three nonadelgid species. L. osakensis fed and laid more eggs on A. tsugae over all the other host species. The difference was greater in paired-choice tests. L. osakensis completed development only on A. tsugae. The overall results of the host range study indicate that L. osakensis is a specific predator of A. tsugae, supporting its potential as a biological control agent, and is not a threat to nontarget species populations.

The hemlock woolly adelgid, Adelges tsugae Annand (Hemiptera: Adelgidae), native to western North America and Asia, was accidentally introduced from Japan to the eastern United States. To potentially establish biological control of A. tsugae, we released a predator endemic to western North America, Laricobius nigrinus Fender (Coleoptera: Derodontidae), from 2003 to 2005, in 22 localities from Georgia to Massachusetts. Release sites spanned the invasive range of the adelgid across five United States Department of Agriculture plant hardiness zones (5a to 7a). Release sizes were 75, 150, 300, 600, or 1,200 adult L. nigrinus per site in the fall, winter, early spring, or sequentially (i.e., fall or winter and early spring). We monitored establishment by annual sampling for L. nigrinus adults with beat sheets and for L. nigrinus larvae by branch clipping. At the end of 3 yr, L. nigrinus was established in 13 of the 22 sites. The following variables were evaluated for their correlation with the numbers of L. nigrinus larvae and adults recovered and for their effect on establishment (scored as F(3) presence/absence): (1) Minimum winter temperature at the release site, (2) A. tsugae density at the time of release, (3) release size, and (4) release season. Only minimum winter temperature was correlated with larval recoveries and no variables were correlated with adult recoveries. Logistic regression modeling found that establishment was positively related to minimum winter temperature and release size. We recommend smaller release sizes in warm areas where establishment probability was high (i.e., zones 7a, 6b, and 6a) and larger release sizes in cold areas where establishment probability was low (i.e., zones 5b and 5a). Releases during fall-early spring and across the range of A. tsugae densities tested were successful.

Internal and external features of larvae of Nosodendron fasciculare were examined and compared to character states found in other groups of Derodontoidea and Bostrichoidea. Synapomorphic larval features indicate a sistergroup relationship between Nosodendridae and Derodontidae: tubercular surface structure, body compressed dorsoventrally, tergites with lateral projections, spiracles located on tubular processus. These families share three derived character states with Jacobsoniidae in one of two equally parsimonious trees. However, the monophyletic origin of Nosodendridae + Derodontidae + Jacobsoniidae is not sufficiently established at present. The monophyly of Bostrichoidea (Dermestidae + Bostrichidae + Anobiidae + Ptinidae) is suggested by hypognathism. Larvae of these families are characterized by the absence of the mandibular mola and a robust apical part of the mandible. The monophyly of Bostrichidae + Anobiidae + Ptinidae is indicated by a C-shaped, grub like body and the abdominal apex formed by an enlarged and rounded segment IX. Bostrychiformia are probably paraphyletic. A closer relationship between Bostrichoidea with Cucujiformia is suggested by the possession of cryptonephric malpighian tubules in adults. The specific type of cryptonephridism in Bostrichoidea is probably derived from this condition and is considered autapomorphic. The monophyly of Nosodendridae (Nosodendron) is supported by several autapomorphies. The assignment of the supposed larva of Nosodendron ovatum remains unclear. An inclusion of the dermestid genus Orphilus in Nosodendridae is rejected. Muscular features of larvae of Nosodendron (and Derodontus) are largely plesiomorphic.

The biology and temperature-dependent development of Laricobius kangdingensis Zilahi-Balogh and Jelinek (Coleoptera: Derodontidae), a newly described predator of hemlock woolly adelgid (HWA), Adelges tsugae Annand (Hemiptera: Adelgidae) were investigated and compared with a related HWA predator, L. nigrinus Fender, that has already been released. As with other Laricobius species, there are four larval instars. The female to male sex ratio was 1:1.1. Mean lifetime fecundity per female was 196.4 eggs and 97.9 eggs for the parental generation (P1) and first filial generation (F1), respectively. Developmental rates at 6, 9, 12, 15, and 18°C were studied between fall 2002 and spring 2004 and used to determine low temperature development thresholds for the egg (2.8°C), and larval (1.6°C) stages. The egg and larval thresholds are lower than those observed for L. nigrinus. Laricobius kangdingensis individuals completed development only at 12 and 15°C; however, the adults did not emerge from aestivation after pupation. Our results suggest that L. kangdingensis may be a promising addition to the complex of predators currently being reared for control of HWA. Laricobius kangdingensis is long-lived, exhibits high fecundity, and can complete development on North American HWA. However, further studies will be necessary to secure its clearance for release, and the source of high mortality in the laboratory must be identified in order to improve its survival for mass-rearing.