Similar dietary but different numerical responses to nonnative tamarisk (<Emphasis Type="Italic">Tamarix</Emphasis> spp.) by two native warblers

Native species can have a range of responses to nonnative introductions, from negative to positive, and understanding how and why native species respond differently to nonnatives remains an important management challenge. Based on differences and similarities in ecology and behavior, we predicted how abundance and diet of two native warblers, Lucy’s warbler (Oreothlypis luciae) and yellow warbler (Setophaga petechia), would differ in habitats with different amounts of nonnative tamarisk trees and the three nonnative insects obligately dependent on tamarisk (Tamarix spp.). Specifically, we predicted that Lucy’s warblers would have similar densities across sites, yellow warbler densities would be inversely related to tamarisk cover, and both warblers, being generalist insectivores, would incorporate tamarisk biocontrol insects in their diet. Based on point counts and fecal samples at six sites along the Virgin River in the southwestern United States, we found that yellow warblers decreased in abundance with increasing tamarisk cover, while Lucy’s warbler abundance did not and that diet of the two warblers did not differ, with both species exhibiting strong selection for the nonnative tamarisk weevil (Coniatus splendidulus) and weak to no selection for the nonnative tamarisk leafhopper (Opsius stactogalus). Both warblers showed negative selection for the tamarisk beetle (Diorhabda carinulata) and its larvae, even when those insects were 10–100 times more abundant during outbreaks. Although both warblers exploited the novel food resources offered by tamarisk, with those insects contributing half or more of total prey biomass, Lucy’s warblers were better able to maintain densities in tamarisk habitats. We hypothesize this was due to the Lucy’s warbler’s ability to exploit a broader array of habitats surrounding tamarisk sites and its cavity nesting habit that buffers its nests from the higher temperatures and lower humidity of tamarisk-dominated habitat. Our results suggest that predictions based on detailed knowledge of the form and function of native and nonnative species can be used to predict native bird response to nonnatives.     

Trail Chemicals of the Convergens Ladybird Beetle, <Emphasis Type="Italic">Hippodamia convergens</Emphasis>, Reduce Feeding and Oviposition by <Emphasis Type="Italic">Diaphorina citri</Emphasis> (Hemiptera: Psyllidae) on Citrus Plants

We investigated feeding and oviposition behavior of the Asian citrus psyllid, Diaphorina citri, when exposed to the foraging trails of the convergens ladybird beetle, Hippodamia convergens. Diaphorina citri females feeding on citrus leaves directly exposed to the ladybird adults or treated with trail extract excreted significantly less honeydew droplets than controls. The trail chemicals of the ladybird beetle also decreased oviposition by D. citri females on citrus. In a no-choice experiment, D. citri females preferred to oviposit on control flush and plants than those with ladybird trail-extract treatments. In two-choice experiments, 68.0% of D. citri released into cages exhibited strong selection preference for settling and eventual oviposition on control plants than plants treated with ladybird trail extract. Diaphorina citri eggs were found on all new leaf flush of control plants, whereas only 29.5% of flush on treatment plants were selected for oviposition. The trail chemical deposited by the convergens ladybird beetle elicits repellency of D. citri feeding and oviposition. Therefore, the trail chemicals my contain components that could be useful for behavior-based management of D. citri and HLB disease by reducing psyllid feeding and oviposition.     

Examination of dogbane beetle (<Emphasis Type="Italic">Chrysochus auratus</Emphasis>) feeding and phenology on spreading dogbane,and considerations for biological control

We carried out experiments that considered the feeding, phenology, and biocontrol potential of dogbane beetle, Chrysochus auratus, on spreading dogbane, Apocynum androsaemifolium, a native perennial weed in lowbush blueberry (Vaccinium angustifolium). In no-choice host-feeding experiments, adult beetles did not feed upon common milkweed (Asclepias syriaca), periwinkle (Vinca minor), wild raisin (Viburnum cassenoides), and lowbush blueberry, all plants related to spreading dogbane or found around lowbush blueberry fields. In a field experiment, significant decreases in spreading dogbane total and foliar weight occurred at a density of 16 beetles per ramet, but not at lower beetle densities. In our Nova Scotia (NS) field sites, beetles were present for 8–12 weeks, beginning in late June or early July (225–335 growing degree days, GDD). Beetle abundance peaked at 4–7 beetles/m² and occurred at 357–577 GDD, which temporally coincides with the incidence of mature spreading dogbane plants in the field. The results suggest that although inundations of C. auratus could cause significant defoliation of spreading dogbane, natural populations of the beetle probably could not satisfactorily suppress development of this weed as a stand-alone control tactic. Conservation and augmentation of C. auratus populations should nonetheless be encouraged in integrated management programs for spreading dogbane.     

Nutritional symbionts of a putative vector, <Emphasis Type="Italic">Xyleborus bispinatus</Emphasis>, of the laurel wilt pathogen of avocado, <Emphasis Type="Italic">Raffaelea lauricola</Emphasis>

Ambrosia beetles subsist on fungal symbionts that they carry to, and cultivate in, their natal galleries. These symbionts are usually saprobes, but some are phytopathogens. Very few ambrosial symbioses have been studied closely, and little is known about roles that phytopathogenic symbionts play in the life cycles of these beetles. One of the latter symbionts, Raffaelea lauricola, causes laurel wilt of avocado, Persea americana, but its original ambrosia beetle partner, Xyleborus glabratus, plays an uncertain role in this pathosystem. We examined the response of a putative, alternative vector of R. lauricola, Xyleborus bispinatus, to artificial diets of R. lauricola and other ambrosia fungi. Newly eclosed, unfertilized females of X. bispinatus were reared in no-choice assays on one of five different symbionts or no symbiont. Xyleborus bispinatus developed successfully on R. lauricola, R. arxii, R. subalba and R. subfusca, all of which had been previously recovered from field-collected females of X. bispinatus. However, no development was observed in the absence of a symbiont or on another symbiont, Ambrosiella roeperi, recovered from another ambrosia beetle, Xylosandrus crassiusculus. In the no-choice assays, mycangia of foundress females of X. bispinatus harbored significant colony-forming units of, and natal galleries that they produced were colonized with, the respective Raffaelea symbionts; with each of these fungi, reproduction, fecundity and survival of the beetle were positively impacted. However, no fungus was recovered from, and reproduction did not occur on, the A. roeperi and no symbiont diets. These results highlight the flexible nature of the ambrosial symbiosis, which for X. bispinatus includes a fungus with which it has no evolutionary history. Although the “primary” symbiont of the neotropical X. bispinatus is unclear, it is not the Asian R. lauricola.     

Multiple plant traits influence community composition of insect herbivores: a comparison of two understorey shrubs

Structural and nutritional plant traits influence the ability of insect herbivores to locate, consume and persist on their hosts yet it is uncommon for ecologists to consider how multiple plant traits influence insect community composition. We sampled herbivorous insects on two understorey shrub species common to eucalypt forests of south-eastern Australia, namely Cassinia arcuata (Asteraceae) and Daviesia ulicifolia (Fabaceae). Regression analyses were used to assess the relative influence of plant structure (canopy volume), nutritional quality (macronutrients and total phenolics) and plant productivity (leaf litter) on insect abundance and species richness. Total N content of D. ulicifolia was significantly higher than C. arcuata, while the concentrations of P, K, Ca and Mg were higher in C. arcuata. Total phenolics and leaf litter were significantly lower in D. ulicifolia compared to C. arcuata. Insect composition was similar between the two shrubs but C. arcuata supported greater abundances. Canopy volume and the macronutrients P and Ca were important predictors of insect abundance on C. arcuata, whereas canopy volume alone, but neither plant productivity nor macronutrients, influenced the abundance of insects on D. ulicifolia. Ca was an important predictor of insect species richness on C. arcuata and P was an important predictor on D. ulicifolia. By quantifying a range of plant traits, we have provided an understanding of factors likely to influence the composition of herbivorous insects inhabiting these two shrubs. Traits including leaf architecture, foliar morphology and volatile terpenoids may yet explain the greater number of insects on C. arcuata since they influence the availability of microhabitats and apparency of host plants.     

Riparian bird density decline in response to biocontrol of <Emphasis Type="Italic">Tamarix</Emphasis> from riparian ecosystems along the Dolores River in SW Colorado,USA

Biocontrol of invasive tamarisk (Tamarix spp.) in the arid Southwest using the introduced tamarisk beetle (Diorhabda elongata) has been hypothesized to negatively affect some breeding bird species, but no studies to date have documented the effects of beetle-induced defoliation on riparian bird abundance. We assessed the effects of tamarisk defoliation by monitoring defoliation rates, changes in vegetation composition, and changes in density of six obligate riparian breeding bird species at two sites along the Dolores River in Colorado following the arrival of tamarisk beetles. We conducted bird point counts from 2010 to 2014 and modeled bird density as a function of native vegetation density and extent of defoliation using hierarchical distance sampling. Maximum annual defoliation decreased throughout the study period, peaking at 32–37% in 2009–2010 and dropping to 0.5–15% from 2011–2014. Stem density of both tamarisk and native plants declined throughout the study period until 2014. Density of all bird species declined throughout most of the study, with Song Sparrow disappearing from the study sites after 2011. Blue Grosbeak, Yellow-breasted Chat, and Yellow Warbler densities were negatively related to defoliation in the previous year, while Lazuli Bunting exhibited a positive relationship with defoliation. These findings corroborate earlier predictions of species expected to be sensitive to defoliation as a result of nest site selection. Tamarisk defoliation thus had short-term negative impacts on riparian bird species; active restoration may be needed to encourage the regrowth of native riparian vegetation, which in the longer-term may result in increased riparian bird density.     

Coleoptera associated with <Emphasis Type="Italic">Fomitopsis pinicola</Emphasis> (Sw.:Fr.) Karst. (Basidiomycetes,Aphyllophorales) in the forests of the Urals and Transurals

A detailed characteristic of the beetle fauna associated with Fomitopsis pinicola (Sw.: Fr.) Karst. (Basidiomycetes, Aphyllophorales) in the Urals and Transurals is given. Thirty species from 14 families have been revealed, the commonest species including Eridaulus jacquemarti Mel., Ennearthron laricinum (Mel.) (Ciidae), Dorcatoma dresdensis Hbst., D. lomnickii Rtt., D. punctulata Muls. (Anobiidae), Diaperis boleti (L.) (Tenebrionidae), Scaphisoma agaricinum (L.), S. inopinatum Löbl, S. subalpinum Rtt. (Scaphidiidae), Ostoma ferruginea (L.), and Peltis grossa (L.) (Peltidae). The main trends in the ecological and trophic specialization of mycetophilous beetles are discussed, and some regularities of formation of mycetophilous complexes at different stages of the trees fungi fruit body development are revealed.     

New data on the changes in the abundance and distribution of several species of beetles (Coleoptera) in European Russia and the Caucasus

Changes in the abundance and distribution of selected species of beetles in European Russia and in the Caucasus are reported. Most of these species have been recorded from the Northwestern Caucasus in the last 10–15 years. The abundance and distribution during the last two years have changed most sharply in the introduced species, the Harlequin lady beetle Harmonia axyridis and two East Asian bruchids, Megabruchidius dorsalis and M. tonkineus. In 2016, the latter has been found in Georgia for the first time, and Harmonia axyridis was found in St. Petersburg. Abundance of the weevil Alcidodes karelinii with the range situated mostly east of the Caucasus and Volga River remains in Northwestern Caucasus at about the previous level. The flea-weevil species, a leaf miner on Ulmus pumila, misidentified previously as Orchestes mutabilis, is described in this paper as Orchestes steppensis sp. n. based on the material from Russia, Kazakhstan, Mongolia and Northern China; no its further distribution westward in 2015–2016 has been found. This species, rapidly widening its range in North America in the recent decade, is misidentified there as Orchestes alni. A key for differentiation of Orchestes alni, O. mutabilis and O. steppensis sp. n. is provided with photographs of adults of all three species. Magdalis armigera has increased abundance in Northwestern Caucasus in 2016 and was for the first time found in Northwestern Russia (Pskov Province) in 2015. Regular faunistic surveys during several decades provide a possibility of recording considerable changes in the abundance of some common species of Coleoptera, often associated with changes in their distribution.     

Patterns of floral resource use by two dominant ant species in a biodiversity hotspot

Ecological dominance in ants is often fuelled by carbohydrate intake. Most studies have focused on the importance of invasive ant mutualistic associations with trophobionts whereas few studies have investigated the importance of floral nectar on invasion success. In this study, utilisation of temporarily available floral nectar by the invasive Argentine ant, Linepithema humile, was compared to that of the dominant native ant, Anoplolepis custodiens, within the Cape Floristic Region (CFR), a biodiversity hotspot. The effect of these two focal ant species on species composition and abundance of ground foraging ants as well as floral arthropod visitors in inflorescences of Proteacea species was assessed. Foraging activity, and trophic ecology inferred from the abundance of natural stable isotopes of Carbon (δ¹³C) and Nitrogen (δ¹⁵N), and the ratio of Carbon to Nitrogen (C:N) were compared between the two ant species during three flowering periods. Linepithema humile significantly reduced the abundance and species diversity of both above-ground and floral arthropod species abundance and composition. Linepithema humile increased its foraging activity with increasing nectar availability, switching its diet to a more herbivorous one. Anoplolepis custodiens did not respond as effectively to increasing floral nectar or negatively impact floral arthropod visitors. This study showed that the availability of floral nectar and ability of L. humile to more effectively utilise this temporarily available resource than native ants, can contribute significantly to the further spread and persistence of L. humile in natural environments in the CFR.     

Associational effects against a leaf beetle mediate a minority advantage in defense and growth between hairy and glabrous plants

Based on the accumulation of evidence, the risk of herbivory depends not only on the traits of a plant but also on those of neighboring plants. Despite the potential importance of frequency-dependent interactions in the evolutionary stability of anti-herbivore defense, we know little about such associational effects between defended and undefended plants within a species. In this study, we determined whether the intraspecific associational effects against the oligophagous leaf beetle, Phaedon brassicae, caused a minority advantage in defense and growth between trichome-producing (hairy) and trichomeless (glabrous) plants of Arabidopsis halleri subsp. gemmifera. We experimentally demonstrated that the magnitude of herbivory and the number of adult beetles on hairy plants decreased when hairy plants were a minority, whereas the leaf damage and the beetle abundance did not differ between hairy and glabrous plants when glabrous plants were a minority. By contrast, the larvae of P. brassicae occurred less when hairy plants were a majority. We also found a reciprocal minority advantage in the biomass production for both hairy and glabrous plants. Additionally, the adults tended to attack glabrous leaves more rapidly than hairy ones, particularly when the beetles were starved or experienced glabrous diets. Furthermore, in the absence of herbivory, the growth of hairy plants tended to be slower than glabrous plants, which indicated a cost for the production of trichomes. Our study suggests that associational effects are a mechanism for the maintenance of trichome dimorphism by contributing to negative frequency-dependent growth.     

Dynamic associations between <Emphasis Type="Italic">Ips sexdentatus</Emphasis> (Coleoptera: Scolytinae) and its phoretic mites in a <Emphasis Type="Italic">Pinus pinaster</Emphasis> forest in northwest Spain

The relationship between the pine bark beetle Ips sexdentatus and its phoretic mites in a Pinus pinaster forest in northwest Spain was studied during 2014. Four species of mites were collected, three of them from the body of the beetle—Histiostoma ovalis, Dendrolaelaps quadrisetus and Trichouropoda polytricha—the fourth, Cercoleipus coelonotus, was collected from the sediments. The main aims of this study were to explore (1) mite diversity and related parameters, (2) the location on the body of the (male and female) beetle, as well as mite assemblages, and (3) the seasonal dynamic association between mite species and the beetle. Results indicated that the diversity oscillated around 0.71 through the study period and the most dominant, frequent and abundant mite was H. ovalis. Histiostoma ovalis was found attached to almost all parts of the body (mainly on the elytral declivity and ventral thorax), whereas D. quadrisetus was exclusively found under the elytra, and T. polytricha displayed affinity towards the elytral declivity as well as the ventral thorax. None of the mite species displayed any preference for the sex of the beetle and the most frequent mite assemblage was H. ovalis, T. polytricha and D. quadrisetus all together. Maximum abundance of each phoretic mite species was related with each of the flight peaks of the beetle that would indicate that these mite species use phoresy as a primary method of transport for colonizing new food sources.     

The invasive herb <Emphasis Type="Italic">Lupinus polyphyllus</Emphasis> attracts bumblebees but reduces total arthropod abundance

Invasive plant species generally reduce the abundance and diversity of local plant species, which may translate into alterations at higher tropic levels, such as arthropods. Due to the diverse functional roles of arthropods in the ecosystems, it is critical to understand how arthropod communities are affected by plant invasions. Here, we investigated the impact of the invasive ornamental herb Lupinus polyphyllus (Lindl.) on arthropod communities during its main flowering period in southwestern Finland over two years. The total number of arthropods was about 46% smaller at the invaded sites than at the uninvaded sites in both study years, and this difference was mainly due to a lower abundance of beetles, Diptera, Lepidoptera, and ants. However, the number of bumblebees (particularly Bombus lucorum) was about twice as high at invaded sites compared with uninvaded sites, even though bumblebee richness did not differ between sites. There was no statistically significant difference between invaded and uninvaded sites in the abundances of the other arthropod groups considered (Hymenoptera (excluding bumblebees and ants), Hemiptera, and Arachnida). In addition, L. polyphyllus affected the relative abundance of four arthropod groups, with the order Lepidoptera being less common at invaded sites than at uninvaded sites, while the opposite was true for bumblebees, Hemiptera, and Arachnida. Overall, these results demonstrate that the negative impact of L. polyphyllus on biodiversity goes beyond its own trophic level, suggesting that this species has the potential to alter the abundance of different arthropod groups and, consequently, the structure of arthropod communities at a large scale.     

Defense Responses and Changes in Symbiotic Gut Microflora in the Colorado Potato Beetle <Emphasis Type="Italic">Leptinotarsa decemlineata</Emphasis> under the Effect of Endophytic Bacteria from the Genus Bacillus

Phytophagous insects and host plants have a complex of microsymbionts and make up a united co-evolving system with them. Microsymbiotic complexes are actively involved in stress responses of macrosymbionts. We established that a treatment of potato plants with endophytic bacterial strains Bacillus thuringiensis var. thuringiensis-5689, B. th. var. kurstaki-5351, and Bacillus subtilis 26D decreased the survival rate of the plant feeder, Colorado potato beetle Leptinotarsa decemlineata Say. The B. th. strains suppressed phenoloxidase and acetylcholinesterase activities in the beetle hemolymph. An antagonistic relationship was found between endophytic bacteria B. subtilis 26D and beetle symbiotic bacteria from the genera Acinetobacter and Enterobacter, with the former being able to suppress the growth of endophytic colonies. The recombinant B. subtilis strain 26D Cry, containing the B. th. var. kurstaki δ-endotoxin cry1Ia gene, combined the ability of the original B. subtilis 26D strain to suppress the development of beetle symbionts and immune responses with a production of the Cry toxin, thus leading to a high mortality of the phytophage.     

Beetles (Coleoptera) in polar deserts of the Severnaya Zemlya Archipelago

In the course of five expeditions to the Severnaya Zemlya Archipelago, four beetle species were found: Micralymma brevilingue (Staphylinidae), Chrysolina subsulcata, Ch. septentrionalis (Chrysomelidae), and Dienerella filum (Latridiidae). The zonal plant communities do not contain beetles at all. All the species found prefer intrazonal habitats, where the snowless season is prolonged. Only M. brevilingue is common enough in various biotopes of the archipelago. All the beetle species found are wingless, rather small, polytopic and have vast distribution areas (D. filum is a cosmopolitan polyzonal species, and the others are semi-circumpolar arctic forms). Obviously, M. brevilingue should be considered as the most cold-tolerant beetle species of the Northern Hemisphere. This is the first report on the coleopteran fauna in the polar desert zone.     

Two new complete mitochondrial genomes of <Emphasis Type="Italic">Dorcus</Emphasis> stag beetles (Coleoptera,Lucanidae)

The systematics of Dorcus MacLeay has been a long-standing debate. Mitochondrial genomes were widely used to deeply understand the phylogeny of problematic taxa in virtue of their genetic importance and comprehensiveness. To provide more useful genetic data for resolving the systematic disputation of Dorcus stag beetles. The complete mitochondrial genomes of Dorcus hopei and Dorcus seguyi were obtained using the next generation sequencing. Characteristics of the two genomes are explicated through comparing their genome organization and base composition, protein-coding genes and codon usage, intergenic spacers and non-coding region, transfer and ribosomal RNA genes and control region. Phylogenetic relationships were reconstructed using Maximum likelihood and Bayesian inference analyses based on the concatenated nucleotide sequences of 13 PCGs from 9 stag beetles and 3 scarab beetles. The complete mitogenomes of D. hopei and D. seguyi was 16,026 bp/17,955 bp long, respectively. A tandem repeat with the length of 940 bp was presented in the A+T-rich region in D. hopei. An unexpected non-coding region of 332 bp was located between nad2 and trnW in D. seguyi. The phylogenetic analyses robustly supported that D. hopei formed a branch with the generic type of D. parallelipipedus. Whereas D. seguyi was not covered in the branch of (D. hopei?+?D. parallelipipedus), but was sister to them. The results indicated that D. hopei should be a good member of Dorcus MacLeay. The taxonomic status of D. seguyi remained to be studied furtherly.     

Antibiotic-Resistant <Emphasis Type="Italic">Escherichia coli</Emphasis> in Migratory Birds Inhabiting Remote Alaska

We explored the abundance of antibiotic-resistant Escherichia coli among migratory birds at remote sites in Alaska and used a comparative approach to speculate on plausible explanations for differences in detection among species. At a remote island site, we detected antibiotic-resistant E. coli phenotypes in samples collected from glaucous-winged gulls (Larus glaucescens), a species often associated with foraging at landfills, but not in samples collected from black-legged kittiwakes (Rissa tridactyla), a more pelagic gull that typically inhabits remote areas year-round. We did not find evidence for antibiotic-resistant E. coli among 347 samples collected primarily from waterfowl at a second remote site in western Alaska. Our results provide evidence that glaucous-winged gulls may be more likely to be infected with antibiotic-resistant E. coli at remote breeding sites as compared to sympatric black-legged kittiwakes. This could be a function of the tendency of glaucous-winged gulls to forage at landfills where antibiotic-resistant bacterial infections may be acquired and subsequently dispersed. The low overall detection of antibiotic-resistant E. coli in migratory birds sampled at remote sites in Alaska is consistent with the premise that anthropogenic inputs into the local environment or the relative lack thereof influences the prevalence of antibiotic-resistant bacteria among birds inhabiting the area.     

Phototactic behavior of the ambrosia beetle <Emphasis Type="Italic">Platypus quercivorus</Emphasis> (Murayama) (Coleoptera: Platypodidae) before and after flight

The ambrosia beetle Platypus quercivorus (Coleoptera: Platypodidae) is a vector of the pathogenic fungi, Raffaelea quercivora (Ophiostomatales: Ophiostomataceae), which causes Japanese oak wilt disease. Previous studies have shown that the beetle displays positive phototactic behavior; however, the adaptive significance of this behavior remains unclear. We postulated that positive phototaxis is necessary to allow the beetle to fly skyward immediately after emergence from a tree, and that this taxis changes following a certain period of flight. The present study aimed to clarify the changes in phototactic behavior of P. quercivorus before and after flight by using individual beetles emerging from the trunk of a Quercus crispula (Fagales: Fagaceae) tree that was attacked in 2014. The response of 60 beetles to light was tested ten times each, before and after flight in a flight mill. A generalized linear mixed model was constructed to predict the probability of positive phototaxis of P. quercivorus before and after flight. A best-fit model showed that the probability of positive phototaxis was lower after flight than before. The results suggest that positive phototaxis of P. quercivorus is decreased after flight.     

Overwintering ecology of <Emphasis Type="Italic">Philonthus rotundicollis</Emphasis> (Coleoptera,Staphylinidae) in the nest of the carpenter ant <Emphasis Type="Italic">Camponotus herculeanus</Emphasis> on the coast of the Sea of Okhotsk

A widespread rove beetle species, Philonthus rotundicollis, whose distribution range stretches across different climatic zones, including the coldest regions of the Asian northeast, was discovered as an inquiline within the nests of the carpenter ant Camponotus herculeanus on the coast of the Sea of Okhotsk in winter. It remained unclear if the beetles had significant cold-hardiness and whether they overwintered deep in the soil or were confined to particularly warm habitats. To clarify these aspects, the following metrics of cold-hardiness were measured: supercooling point (SCP), freezing point (FP), supercooling capacity (SCP-FP), and temperature minima at the beetles’ overwintering sites. In Ph. rotundicollis, mean SCP was -11.1 ± 0.7°C (ranging from - 7.9 to -18.8°C, n + 15), which was insufficient for successful overwintering even on the coast, since temperature minima in leaf litter during a snow-deficient winter fell to -14°C at the depth of 5 cm and -12°C at 20 cm. The beetles could not burrow deep into stiff soil and made use of crevices in dry peat-like soil layers as well as tunnels of soil- and rootdwelling animals, including carpenter ants. The presence of this rove beetle species in the ant nest was probably due to feeding on ant larvae because, at near-zero temperatures, the activity threshold of the beetles was lower than that of the ants that guarded the larvae.