Description of the stridulatory apparatus of the Far Eastern bark beetles <Emphasis Type="Italic">Polygraphus proximus</Emphasis> Blandford, 1894 and <Emphasis Type="Italic">P. jezoensis</Emphasis> Niisima, 1909 (Coleoptera,Curculionidae: Scolytinae)

The stridulatory organ structure in two Far Eastern bark beetles, Polygraphus proximus and P. jezoensis, is described. The elytro-tergal type of the stridulatory apparatus is found in P. jezoensis. The structure involved in acoustic communication of P. jezoensis is present only in males. The plectrum of P. proximus males is re-described. Similarly to that in P. jezoensis, it is formed by two tubercles at the distal margin of tergite VII. An additional type of stridulatory organ used for the producing of precopulatory courtship signals is described for males of P. proximus. In this type of stridulatory organ, transverse ridges on the costal margin of the elytron act as pars stridens, and the hind tibia, as the plectrum.     

Insects inhabiting the galleries of the four-eyed fir bark beetle <Emphasis Type="Italic">Polygraphus proximus</Emphasis> Blandf. (Coleoptera,Curculionidae: Scolytinae) in Siberia

A review of 28 species of insects from 17 families of 4 orders that inhabit the galleries of the four-eyed fir bark beetle Polygraphus proximus in the area of its invasion in Siberia is given with data on their distribution, trophic associations, occurrence, abundance, and locations. A characteristic of the xylophilous insect community associated with Polygraphus proximus is given. The impact of this invasive species on the composition and structure of the bark beetle consortia in the native ecosystems is shown.     

Flies (Diptera) Associated with <Emphasis Type="Italic">Polygraphus proximus</Emphasis> Blandford, 1894 (Coleoptera,Curculionidae) in Siberia and the Russian Far East

The faunal composition of Diptera (Insecta) inhabiting the galleries of Polygraphus proximus over the territory of Siberia and the Russian Far East was studied. As a result, 14 species of Diptera were discovered representing 8 families. Within its secondary range, the invasive beetle P. proximus Blandford, 1894 is affected not only by the well-known introduced species Medetera penicillata Negrobov, 1970 but also by numerous other widespread predatory flies, such as Medetera excellens Frey, 1909, M. pinicola Kowarz, 1877, Xylophagus cinctus (De Geer, 1776), and Toxoneura ephippium (Zettersted, 1860). Four predatory fly species, M. penicillata, M. signaticornis Loew, 1857, Lonchaea bukowskii Czerny, 1934, and Xylophagus sachalinensis (Pleske, 1925), affect P. proximus within its native range in the Russian Far East. Data on the predation of each species of Diptera on several species of bark beetles testify to their polyphagy. Saprophagous larvae of Dicranomyia modesta (Meigen, 1818), Chalcosyrphus piger (Fabricius, 1794), Xylosciara lignicola (Winnertz, 1867), and Pseudolycoriella unispina (Mohrig et Krivosheina, 1983) were discovered in bark beetle galleries for the first time.     

Host Foraging Behavior of <Emphasis Type="Italic">Dastarcus helophoroides</Emphasis> (Coleoptera: Bothrideridae) Adults,a Coleopteran Parasitoid of <Emphasis Type="Italic">Monochamus alternatus</Emphasis> (Coleoptera: Cerambycidae)

Dastarcus helophoroides adults, a coleopteran parasitoid of Monochamus alternatus, were reared in the laboratory. The objectives of this paper are to investigate the host foraging behavior of D. helophoroides, and the evidence for learning in such behaviors. Choice and no-choice experiments were carried out. The choice experiments show that the number of D. helophoroides adults choosing the Pinus massoniana log infested with M. alternatus larvae was significantly higher than that choosing the blank (a flavorless simulative log made of brown kraftpaper), and the number of D. helophoroides adults choosing the uninfested P. massoniana log was also significantly higher than that choosing the blank. The no-choice experiment shows no significant difference between the number of D. helophoroides adults that chose the infested log and that chose the uninfested log, despite previous experience with uninfested log, infested log, or neither of them. No evidence of learning in host foraging behavior in D. helophoroides adults was found. The results indicate that the volatile chemicals emitted by uninfested P. massoniana logs and infested logs with M. alternatus larvae are equally attractive to D. helophoroides.     

The Structure and Density of Aggregations of the Hermit Crab <Emphasis Type="Italic">Pagurus proximus</Emphasis> Komai, 2000 in Epibiosis of the Brown Alga <Emphasis Type="Italic">Costaria costata</Emphasis> (C. Agardh) De A. Saunders, 1895 in the Sublittoral Zone of Vostok Bay,Sea of Japan

A study of epibiosis of the brown alga Costaria costata in the sublittoral zone of Vostok Bay, Sea of Japan during the spring and summer of 2016 showed that hermit crabs of the following four species accounted for approximately 85% of the total biomass: Pagurus proximus, P. minutus, P. brachiomastus, and P. middendorffii. Of these, the most abundant one (96.5% of the total number of hermit crabs) was P. proximus, the mean aggregation density of which on C. costata (429 ± 221 ind./m²) was higher by an order of magnitude than that in the adjacent area of the bouldery bottom. The size ranges of males and females of this species in aggregations on boulders and those on C. costata were similar, with a predominance of larger individuals on algae. In the size–frequency distribution, three groups of individuals corresponding to three size–age cohorts were differentiated. The male-to-female ratio was 1 : 1.7. Hermit crab aggregations on C. costata are ephemeral; their existence is determined by the duration of the period of algae development, that is, from late spring to the middle of the summer.     

Additions to the check list of bark beetles (Coleoptera,Curculionidae: Scolytinae) from Leningrad Province,Russia

The field work of the authors during the last 16 years in both the western and the eastern parts of Leningrad Province, Russia, has resulted in the addition of 7 species to the regional list of bark beetles, namely: Hylurgus ligniperda F., Crypturgus subcribrosus Egg., Pityogenes irkutensis Egg., Scolytus mali Bechst., S. scolytus F., S. pygmaeus F., and Xyleborinus attenuatus Blandf. Of these species, P. irkutensis occurs only in the eastern districts of Leningrad Province, C. subcribrosus, over the whole territory, and the remaining species, only in the western districts. We suggest excluding Polygraphus proximus Blandf. from the regional faunal list. As a result, the updated list of the bark beetle species of Leningrad Province comprises 75 taxa. New data on findings of rare species in the region are considered.     

Female Responses to Synthetic Pheromone and Plant Compounds in <Emphasis Type="Italic">Agriotes brevis</Emphasis> Candeze (Coleoptera: Elateridae)

Traps baited with synthetic pheromone components of Agriotes brevis [geranyl butanoate + (E,E)-farnesyl butanoate] captured significantly higher numbers of not only male, but also female beetles, compared to unbaited controls. Catches of both sexes showed a clear positive relationship with increasing doses. In electroantennogram tests, antennal responses of females and males to a number of known Agriotes pheromone components, identified from pheromone glands, showed a similar trend, with geranyl butanoate eliciting the strongest responses. This suggests that the female and male A. brevis antennae are similar with respect to the perception of pheromone compounds, and female beetles have the sensory capabilities to perceive the pheromone components which they produce. Addition of the plant-derived compounds (Z)-3-hexenyl acetate, methyl benzoate, (Z)-3-hexenol and methyl salicylate (identified earlier from foliage as attractive for A. brevis) to the synthetic pheromone significantly increased catches. All the above results suggest that geranyl butanoate and (E,E)-farnesyl butanoate are constituents of an aggregation pheromone of A. brevis, in contrast to the general view of click beetle pheromones being “classical” sex pheromones. These findings could be useful for more precise monitoring and forecasting of damage, based on female catches.     

The stability of the pheromones of xylophagous insects to environmental factors: An evaluation by quantum chemical analysis

The ground and excited states of the pheromone molecules produced by xylophagous insects (the bark beetle Ips typographus L., the black fir sawyer beetle Monochamus urussovi Fisch., and the black pine sawyer M. galloprovincialis Oliv.) were modeled using a quantum chemical method utilizing DFT (density functional theory) with the B3LYP functional. The absorption wavelengths (energies) and dipole moments were calculated; the transitions of electrons from occupied to empty molecular orbitals were considered. The computed data were used to assess the stability of pheromone molecules exposed to environmental factors, such as solar radiation and humidity.     

Reproductive tables of predatory phytoseiid mites (<Emphasis Type="Italic">Phytoseiulus persimilis,Galendromus occidentalis</Emphasis>, and <Emphasis Type="Italic">Neoseiulus cucumeris</Emphasis>)

Feeding of predatory mites (Phytoseiulus persimilis, Galendromus occidentalis, and Neoseiulus cucumeris) on different life stages of Tetranychus atlanticus under optimal conditions was studied. Daily and total consumption of prey by predators and selection of prey of different life stages were studied for 5 days and for the entire feeding period. Average daily food consumption [number of individuals] for the entire life period of mature mite females constituted 0.43 females + 5.0 [nymphs and males] + 3.4 eggs of Tetranychus atlanticus in P. persimilis; 0.12 females + 3.70 [nymphs and males] + 3.10 eggs in G. occidentalis; and 0.19 females + 4.10 [nymphs and males] + 3.50 eggs in N. cucumeris. During the entire period of feeding, P. persimilis preferred large individuals and at the postembryonic stages selected prey to a greater extent than G. occidentalis and N. cucumeris (61.8 and 55.1%, respectively). The use of a 5-day express-method is possible for estimation of some biological characteristics of phytoseiids that previously consumed the same food for a long period. In other cases, analysis of characteristics for the entire life period is necessary.     

Detection of <Emphasis Type="Italic">Rickettsia</Emphasis> spp. in ticks parasitizing toads (<Emphasis Type="Italic">Rhinella marina</Emphasis>) in the northern Brazilian Amazon

This study evaluated rickettsial infection in ticks collected on toads from the northern Brazilian Amazon (Amapá state), where to our knowledge there are neither records of ticks from amphibians nor rickettsial infections in ticks. During 2016–2017, a total of 22 free-living toads were captured and identified as Rhinella marina. Overall, 12 (54.5%) toads were parasitized by a total of 97 ticks (6 males, 39 females, 31 nymphs, 21 larvae), giving a mean intensity of 8.1 ticks per infested toad. Two tick species were morphologically identified: Amblyomma rotundatum Koch (31 females, 14 nymphs), and Amblyomma dissimile Koch (6 males, 8 females, 17 nymphs). The 21 larvae were morphologically denoted as Amblyomma sp. Five toads were co-infested by A. rotundatum and A. dissimile. Morphological identifications were confirmed by nucleotide sequencing of fragments of the mitochondrial genes 16S rDNA, 12S rDNA and/or COX1. A total of 54 ticks were analyzed for the presence of rickettsial DNA. Eleven (9 females and 2 nymphs) out of 14 A. rotundatum ticks contained Rickettsia bellii. None of the 25 specimens of A. dissimile (6 males, 6 females, 13 nymphs) contained amplifiable rickettsial DNA. From 15 Amblyomma sp. larvae, a pool of 10 individuals contained Rickettsia sp. strain Colombianensi. Sequencing of the 16S rDNA amplicon derived from the positive pool yielded a sequence of A. dissimile. We detected Rickettsia sp. strain Colombianensi for the first time in Brazil. Prior records of this agent were restricted to Colombia and Honduras. In addition, we report the presence of A. rotundatum for the first time in the state of Amapá, where the only other record of A. dissimile was registered over 20 years ago.     

Comparative study on intestinal bacterial communities of <Emphasis Type="Italic">Boleophthalmus pectinirostris</Emphasis> and <Emphasis Type="Italic">Periophthalmus magnuspinnatus</Emphasis> with different sexes and feeding strategies

Intertidal mudflats are unique, highly productive ecosystems. Boleophthalmus pectinirostris and Periophthalmus magnuspinnatus are common fish species that are distributed in the intertidal mudflats of the Yangtze Estuary in China. They perform important ecological functions and have different feeding strategies. Herein, we studied the intestinal microbial diversity and structure of wild B. pectinirostris and P. magnuspinnatus with different sexes and feeding strategies during their breeding season. Gut samples of B. pectinirostris and P. magnuspinnatus individuals (female:male ratio?=?1:1) were collected and subjected to high-throughput DNA sequencing. The results showed Proteobacteria was the most dominant phylum in all the four sample groups: 73.5% in the males and 52.6% in the females of B. pectinirostris and 40.2% in the males and 40.9% in the females of P. magnuspinnatus. Aeromonas, Shewanella, Halomonas, and Acinetobacter of the phylum Proteobacteria were dominant genera in all the sample groups and accounted for 62.13% of the ten dominant genera. The diversity of the intestinal microflora in the omnivorous P. magnuspinnatus was significantly higher (P?<?0.05) than that in the herbivorous B. pectinirostris. Beta diversity, including PCoA and UPGMA of unweighted UniFrac distances, showed that B. pectinirostris samples were clustered together, and P. magnuspinnatus samples were clustered together, implying the effect of the feeding habits on the microbial community structure is more considerable than that of sex.     

The Parasitic Fauna of Common Species of Hermit Crabs of Vostok Bay (Sea of Japan)

The parasitic fauna of common species of hermit crabs was investigated in Vostok Bay (the northwestern Sea of Japan). Pagurus proximus and Areopaguristes hirsutimanus had no parasites. The average prevalence of rhizocephalan infestation in other five species of hermit crabs ranged from 5.67 to 20.83%. The prevalence of the isopod Parapseudione lata on hermit crabs did not exceed 1%, the prevalence of infestation with the isopod Athelges takanoshimensis was significantly higher, reaching 14.58% in Pagurus middendorffii. Parasitism by the isopod P. lata on the hermit crabs Pagurus minutus and P. ochotensis, as well as parasitism by the rhizocephalan Peltogaster reticulata on P. minutus were recorded for the first time. Several variants of simultaneous infestation with two parasitic species were found. The decline in the abundance of P. middendorffii accompanied by the high prevalence of parasites, primarily the colonial rhizocephalan Peltogasterella gracilis, suggests that parasite invasion may play a more significant role in regulating the abundance of hermit crabs than was previously assumed.     

Gene pool state and degree of infestation by bark beetle (<Emphasis Type="Italic">Ips tipographus</Emphasis> L.) of Norway spruce (<Emphasis Type="Italic">Picea abies</Emphasis> L. Karst.) natural populations and planted stands in Moscow region

A comparative analysis of the gene pool state in natural populations and planted stands of Norway spruce and the degree of their infestation by the bark beetle in the Moscow region was conducted taking into account the dynamic state of communities (4 populations, 148 samples, 24 isoenzyme loci). The degree of infestation by the bark beetle of conditionally native communities is 0%; for planted stands, it is 90–100%; and for a short-term community, it is 15–20%. The comparison of “healthy” populations and those infested with bark beetle by average values of observed heterozygosity (H _O) detected no significant differences. However, the test on allelic frequency heterogeneity demonstrated the difference of planted stands from conditionally native populations both by three loci (Fe-2, Idh-1, Mdh-3) and by the totality of 18 polymorphic isoenzyme loci; the short-term population differs from conditionally native population only by two loci. The value of the inbreeding coefficient by the Idh-1 locus is significantly higher in both populations infested with the bark beetle than in “healthy” populations. The results of conducted studies demonstrate the necessity of continuation of the study on the gene pool state in Norway spruce populations owing to the degree of their infestation by the bark beetle along with the study on the dynamic state of the communities; this can provide a key to solving the problem of the forest preservation from pests.     

Detection of <Emphasis Type="Italic">Rickettsia</Emphasis> spp. in ticks associated to wild mammals in Northeastern Brazil,with notes on an undetermined <Emphasis Type="Italic">Ornithodoros</Emphasis> sp. collected from marsupials

We report tick infestations and rickettsial detection in ticks infesting free-living wild mammals (Monodelphis domestica, Tolypeutes tricinctus, Thrichomys inermis and Kerodon rupestris) captured in the Caatinga ecoregion of Bahia state, northeastern Brazil, during September to December 2016. Overall, 117 ticks (61 larvae, 25 nymphs, 25 males, 6 females) belonging to two genera, and at least three species were collected: Amblyomma auricularium, Amblyomma parvum, Amblyomma sp., Ornithodoros rietcorreai and an unidentified Ornithodoros sp. We provide new host records to the rodent T. inermis parasitized by larva and nymphs of A. auricularium and to the marsupial M. domestica infested by larvae of A. auricularium. Furthermore, we describe new tick-host association for larvae of O. rietcorreai on the rodents K. rupestris and T. inermis. Concerning tick-Rickettsia associations, we detected Rickettsia amblyommatis and an uncharacterized species of Rickettsia belonging to the spotted fever group (SFG) in both A. auricularium and A. parvum. Additionally, ‘Candidatus Rickettsia andeanae’ was detected in A. parvum as well.     

Distribution and habitats of <Emphasis Type="Italic">Phengaris</Emphasis> (<Emphasis Type="Italic">Maculinea</Emphasis>) butterflies and population ecology of <Emphasis Type="Italic">Phengaris</Emphasis><Emphasis Type="Italic">teleius</Emphasis> in China

Many species of the butterfly genus Phengaris are regarded as endangered in many parts of their distribution. Several species are also widely distributed across northern China. Due to land use change and overgrazing, their habitats are declining and many patches have been lost. This paper investigates the distribution and habitats of the Chinese Phengaris species (of the subgenus Maculinea). Shrub-grassland near forests seem the most frequent habitat for Phengaris, while flat open grasslands are mostly over-grazed and thus survival for Phengaris butterflies there seems difficult. Throughout Europe, P. teleius is an endangered species, while there is still no information on its status in China. To improve the knowledge on the population ecology of P. teleius, its population structure, adult behaviour and movement were studied through mark–release–recapture methods in the Qinling Mountains of Taibai County. Eight grassland patches which were potentially suitable were found in the area in 2013. In total, 480 individuals (274 females) were marked, resulting in an overall recapture rate of 16 %. The average daily population size was 44 butterflies (±23 SD) during the adult flight period. Sixty-seven percent of the females and 38 % of the males moved less than 50 m, and 17 % of recaptured females and 38 % of males moved more than 200 m. The mean movement distance was 107 ± 177 m for males and 182 ± 122 m for females. The majority of the recaptures (86 %) were made within the patches, only a few individuals (14 %) moved between patches. Due to human disturbance and destruction, all of the eight potentially suitable patches are becoming smaller and increasingly isolated, thus these populations of P. teleius may face an increasing risk of extinction, which may well be a tip of the iceberg of habitat loss and fragmentation of P. teleius in Taibai County and possibly beyond. Hence we hope our initial study of P. teleius could have positive impacts on the conservation of Phengaris butterflies in China.     

Morphofunctional characterization of the reproductive system of the gastropods <Emphasis Type="Italic">Littorina brevicula,L. mandshurica</Emphasis>, and <Emphasis Type="Italic">Nucella heyseana</Emphasis> from uncontaminated and contaminated areas of Peter the Great Bay,Sea of Japan

The structure and state of the reproductive system were studied in the periwinkles Littorina brevicula and L. mandshurica from the coastal area of Vladivostok and in the dogwhelk Nucella heyseana from the protected area of Vostok Bay and from contaminated sites in Amursky Bay. These species were investigated for the presence of imposex and intersex (pathological changes caused by endocrine disruption under the influence of toxic substances). The pathological changes revealed in the gonads of Littorina were oocyte resorption and lipofuscin accumulation; an intersex condition was not found. Imposex specimens (with penis formation) were found among Nucella females from Amursky Bay. The relative penis length in females was 25% of the penis length in males. This kind of pathology was not found in Nucella from clean waters of Vostok Bay.     

Biology of xylophilous larvae of the rhagionid flies <Emphasis Type="Italic">Chrysopilus dives</Emphasis> and <Emphasis Type="Italic">Chrysopilus nigrifacies</Emphasis> (Diptera,Rhagionidae)

The larval morphology and biology of two species of rhagionid flies (Diptera, Rhagionidae) from the Russian Far East are described for the first time. Larvae of Chrysopilus dives Loew develop in the tunnels of xylobiont insects in the trunks of ash trees. Larvae of Ch. nigrifacies Nagatomi were found under the bark of the elm, Sakhalin cork tree, birch, and fir. Morphological characteristics of larvae of Chrysopilus are discussed.     

The fungal matrices of <Emphasis Type="Italic">Ophiostoma ips</Emphasis> hinder movement of the biocontrol nematode agent, <Emphasis Type="Italic">Deladenus siricidicola</Emphasis>, disrupting management of the woodwasp, <Emphasis Type="Italic">Sirex noctilio</Emphasis>

Deladenus (=?Beddingia) siricidicola (Tylenchida: Neotylenchidae) is the most effective biocontrol agent used against the invasive wood wasp, Sirex noctilio (Fabricius) (Hymenoptera: Siricidae). The nematodes feed and reproduce on the wood-inhabiting fungus, Amylostereum areolatum (Chaillet ex Fr.) Boidin (Russulales: Amylostereaceae) and parasitise larvae of S. noctilio. In the nematode biocontrol program, the nematodes are inoculated into herbicide-weakened ‘trap trees’. Recent declines in nematode parasitism of S. noctilio in Australia have coincided with an increased incidence of an exotic bark beetle, Ips grandicollis (Eichhoff) (Coleoptera: Curculionidae), attacking trap trees and vectoring a wood-inhabiting fungus, Ophiostoma ips (Rumbold) Nannfelt (Ophiostomatales: Ophiostomataceae), which may inhibit migration of the nematode within the tree to the detriment of S. noctilio biocontrol. Several in vitro and in vivo experiments were conducted to investigate the effect of fungal interactions on the ability of D. siricidicola to locate and reproduce on A. areolatum. Deladenus siricidicola showed preference to A. areolatum in the presence and absence of O. ips, but the presence of O. ips negatively affected the choice response and the number of eggs laid by the nematodes. Deladenus siricidicola was unable to survive and reproduce on O. ips. Results give a clearer understanding of the choice response of D. siricidicola in I. grandicollis infested trees, explaining the disruptive impact of bark beetles on biocontrol of S. noctilio, an effect that could extend from Australia to other important pine growing countries.     

Behavioral responses of <Emphasis Type="Italic">Hyalesthes obsoletus</Emphasis> to host-plant volatiles cues

The polyphagous planthopper Hyalesthes obsoletus Signoret is considered to be the principal vector of stolbur phytoplasma, which is associated with yellow diseases of grapevine. To explore the possibility of developing novel control strategies, the behavioral responses to six synthetic mixtures and nine single compounds, previously identified from the headspace of Vitex agnus-castus L. (chaste tree) and Urtica dioica L. (nettle), were investigated in Y-tube bioassays. Choice tests revealed differences in the behavioral responses of males and females to the volatiles that they were exposed to. Males were attracted to a mixture containing (E)-β-caryophyllene, 1,8-cineole, (E,E)-α-farnesene, (E)-β-farnesene, and methyl salicylate (mixture 2). The addition of methyl benzoate to this five-compound mixture (mixture 3) did not attract males but elicited positive responses in females. Furthermore, females were attracted to a mixture containing (E)-β-caryophyllene, (E,E)-α-farnesene, (Z)-3-hexenyl acetate, (Z)-3-hexen-1-ol, and benzothiazole (mixture 4), but here addition of methyl salicylate (mixture 5) did not attract females. Neither males nor females showed attractivity or repellency toward the singly tested compounds. This study enhances knowledge on the interaction of insect behaviorally effective constituents in complex plant volatile mixtures. The attractive mixtures of plant volatiles identified suggest the possibility of using them in monitoring and management of H. obsoletus.