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In this study, we conducted a field survey in Aichi Prefecture, central Japan, to clarify whether rodent activity is affected by the presence or absence of dead culms of the dwarf bamboo Sasa borealis, a species characterized by a 120-year cycle of large-scale flowering, seeding, and dying. We found that a relatively larger number of wood mice, Apodemus speciosus and Apodemus argenteus, were caught using Sherman live traps in areas with dead S. borealis culms than in areas lacking the culms, thereby indicating that S. borealis culms, even if dead and leafless, can function as shelters in which the mice can evade predation. However, in the years when A. speciosus was abundant, A. argenteus avoided areas inhabited by A. speciosus and was restricted to areas lacking dead culms, which were devoid of shelter. A feeding experiment using Castanea crenata acorns clearly revealed that a larger number of acorns were foraged by mice in areas containing dead culms. Moreover, in the area with dead culms, the mice preferentially removed sound acorns prior to taking acorns that had been vacated by infesting moth larvae. These findings indicate that the shelter function of dead culms enables mice to carefully select sound acorns, which are nutritionally more beneficial than those that have been infested by moth larvae. [ABSTRACT FROM AUTHOR]

Temperature is essential for the survival and development of eggs. Some anurans have evolved and developed foam nesting traits, with thermal insulation considered to be among their functions. Foam‐nesting frogs tend to exhibit reproductive plasticity. For example, they oviposit on both trees and the ground. How such plasticity affects foam nest function is of major relevance and is likely related to the adaptation of foam nesting frogs. However, this has not been well studied. In this study, we examined the interaction between foam nest site, foam nest function, and egg fate using the Japanese green tree frog, Zhangixalus arboreus, and analysed how nest site differences (arboreal or terrestrial) affect the thermal function of foam nests. We compared the thermal functions of foam nests between arboreal and terrestrial oviposition sites of Z. arboreus. We artificially replaced half of the arboreal nests with terrestrial environments and recorded temperature in and outside of the experimental terrestrial nest and original arboreal nests. We also examined egg survival and hatching rates for all the nests. The results indicated superior heat insulation in terrestrial nests, with warmer temperatures inside than outside the nests, especially at night, which led to a high egg survival rate. Therefore, terrestrial ovipositing should be valid under cold weather conditions. This may be related to the evolutionary history of oviposition site plasticity of this genus, which originally had an arboreal oviposition trait but evolved into terrestrial site use owing to global cooling. Our novel insights into the evolution and adaptivity of foam nesting and oviposition site use in Z. arboreus make an important contribution to animal ecology. [ABSTRACT FROM AUTHOR]

Bambusoideae is a taxon of mass‐flowering monocarpic perennials with a long life cycle. Forest ecosystems are affected by Bambusoideae seeding and death events in various ways, including an increased abundance of Apodemus spp. The utilization and preference of dwarf bamboo seeds over tree seeds by field mice remain elusive. Therefore, we aimed to determine whether field mice prefer dwarf bamboo to tree seeds. We examined one dwarf bamboo species (Sasa borealis) against four tree species with varying acorn/fruit traits (Castanea crenata, Quercus crispula, Fagus crenata, and Lindera triloba). The seeds were placed in a container in a forest among dead S. borealis culms, with an automatic camera monitoring the setup. The examined seeds were mainly foraged by two field mouse species, Apodemus speciosus and Apodemus argenteus, with preference in the following order: C. crenata, L. triloba, S. borealis, F. crenata, and Q. crispula. Our findings indicated that during S. borealis mast seeding years, predation pressure on F. crenata and Q. crispula seeds could be considerably reduced. This suggests that mast seeding might disrupt the normal pattern of survival, and seed dispersal patterns, potentially altering the forest vegetation composition. [ABSTRACT FROM AUTHOR]

The ambrosia beetle, Euwallacea interjectus, is a wood-boring pest and a vector of Ceratocystis ficicola, a pathogenic fungus causing fig (Ficus carica) wilt disease (FWD) in Japan. The ambrosia fungi, Fusarium kuroshium and Neocosmospora metavorans, have been frequently isolated from heads (including mycangia) of wild and reared adult female E. interjectus, respectively. However, the exact mechanisms driving FWD as well as the interactions between F. kuroshium and C. ficicola in fig orchard remain unclear. To verify the role of the mycangial fungi in the FWD progression, fig saplings were subjected to inoculation treatments (T1, F. kuroshium; T2, N. metavorans, reference positive control; T3, C. ficicola; T4, F. kuroshium + C. ficicola, realistic on-site combination). T3 and T4 saplings began wilting approximately 12 days after inoculation, leading to eventual death. Median duration from inoculation to death of the T4 saplings was approximately four days significantly faster than that of the T3 saplings. Xylem sap-conduction test indicated that dysfunction and necrosis area were considerably wider in the T4 saplings than in T3 saplings. These results demonstrate that the synergistic action of F. kuroshium and C. ficicola contributed to accelerated wilting in the saplings. Based on these discoveries, we proposed a model for system changes in the symbiosis between E. interjectus and its associated fungi in FWD in Japan. [ABSTRACT FROM AUTHOR]

Ambrosia beetles bore into host trees, and live with fungi symbiotically that serve as a food source. However, it is challenging to directly observe these beetles in the wild. In this study, Euwallacea interjectus (Blandford) (Coleoptera: Curculionidae: Scolytinae), a pest of fig trees in Japan, were reared under artificial conditions to emulate the behavior of ambrosia beetle. Fungi were isolated from the adult females of E. interjectus to identify the species associated with secondary symbiosis. In total, nine filamentous fungi and one yeast were identified using morphological characteristics and DNA sequence data. Neocosmospora metavorans (Hypocreales: Nectriaceae), Fusarium sp. (Hypocreales: Nectriaceae), that is undescribed, and Meyerozyma guilliermondii (Saccharomycetes: Saccharomycetales) (yeast) were isolated more frequently from the head (including from mycangia, the fungus-carrying organ) than from the thorax and abdomen of adult beetles. Neocosmospora metavorans was the dominant species isolated from 12 out of 16 heads at 200 to 3300 CFUs/head, compared to the primary mycangia fungus from wild beetles, i.e., Fusarium kuroshium (Hypocreales: Nectriaceae). Temperature had a marked effect on fungal growth in the three symbiont species. Our results represent a major paradigm shift in understanding beetle–fungal interactions, as they show specific symbiont switching can occur in different nesting places. [ABSTRACT FROM AUTHOR]

Summary: We isolated two tylenchid species belonging to the Sychnotylenchinae, Sychnotylenchus hibisci n. sp. and Neoditylenchus xiphydriae n. sp., from the bark beetle Ernoporus corpulentus and wood wasp Xiphydria ogasawarai , respectively. Sychnotylenchus hibisci n. sp. is characterised by its moderately stout body in both male and female, gubernaculum to spicule length ratio of one-third or less, crustaformeria structure composed of four columns with six large, rounded cells, and a broad female tail with a rounded terminus. The new species is closely related to S. ulmi , with which it shares body shape and gubernaculum to spicule length ratio, but is distinguished by the female tail shape and several morphometric values. Neoditylenchus xiphydriae n. sp. is characterised by its oval to leaf-shaped male bursa, male tail tip reaching the distal end of, and protruding beyond the bursa, a long post-vulval uterine sac (PUS), and a conical female tail with a narrowly rounded terminus. The species is typologically similar to N. pinophilus but is distinguished by its male spicule shape, gubernaculum to spicule length ratio, and longer PUS. Phylogenetically, the Sychnotylenchinae belongs under the Anguinidae (superfamily Sphaerularioidea) and is closely related to several Ditylenchus , Neotylenchus , Neomisticius , and Ficotylus species. [ABSTRACT FROM AUTHOR]

Summary: A Bursaphelenchus sp. belonging to the B. idius -group was isolated from a bark beetle, Ernoporus corpulentus , which had emerged from dead twigs of Hibiscus tiliaceus collected in Okinawa, in the subtropical region of Japan. In addition to its group-specific characters, i.e. , four lateral lines in both male and female and less developed capitulum and relatively broad blade of the male spicules, the species is characterised by a relatively slender female tail with various tip shapes. Molecularly, the species is close to B. fagi and B. tiliae based on SSU and D2-D3 LSU sequences, but can be clearly distinguished from these two species. The species is described and illustrated herein as B. hibisci n. sp. [ABSTRACT FROM AUTHOR]

Ficus carica plantations in Japan were first reported to be infested by an ambrosia beetle species, identified as Euwallacea interjectus , in 1996. The purpose of this study was to determine the symbiotic fungi of female adults of E. interjectus emerging from F. carica trees infected with fig wilt disease (FWD). Dispersal adults (51 females) of E. interjectus , which were collected from logs of an infested fig tree in Hiroshima Prefecture, Western Japan, were separated into three respective body parts (head, thorax, and abdomen) and used for fungal isolation. Isolated fungi were identified based on the morphological characteristics and DNA sequence data. Over 13 species of associated fungi were detected, of which a specific fungus, Fusarium kuroshium , was dominant in female head (including oral mycangia). The plant-pathogenic fungus of FWD, Ceratocystis ficicola , was not observed within any body parts of E. interjectus. We further discussed the relationship among E. interjectus and its associated fungi in fig tree. [ABSTRACT FROM AUTHOR]

Summary: Two Bursaphelenchus spp. belonging to the eggersi group (subgroup 3) were isolated from bark beetles (Cryphalus spp.). One species, isolated from Cryphalus sp. cf. carpini that emerged from a log of an unidentified broad-leaved tree (considered to be Carpinus sp.) collected in Sugadaira, Nagano, Japan, was identified molecularly and typologically as B. carpini. The other species, isolated from C. abbreviatus that emerged from a dead log of Ficus microcarpa collected in Okinawa, Japan, was differentiated molecularly from other eggersi group species. The new species is characterised by its three-lined lateral field, seven genital papillae with the posteriormost pair forming 'glandpapillae', short and stout male spicule with a strongly dorsally recurved and pointed condylus, small and rectangular male bursal flap with a variable terminus, female vulva with a 'side flap', broadly rounded female tail tip and molecular sequences of the ribosomal RNA region and partial mtCOI gene. The species is described and illustrated herein as B. microcarpae n. sp. [ABSTRACT FROM AUTHOR]

We provide an overview of both traditional and innovative control tools for management of three Xylosandrus ambrosia beetles (Coleoptera: Curculionidae: Scolytinae), invasive species with a history of damage in forests, nurseries, orchards and urban areas. Xylosandrus compactus, X. crassiusculus and X. germanus are native to Asia, and currently established in several countries around the globe. Adult females bore galleries into the plant xylem inoculating mutualistic ambrosia fungi that serve as food source for the developing progeny. Tunneling activity results in chewed wood extrusion from entry holes, sap outflow, foliage wilting followed by canopy dieback, and branch and trunk necrosis. Maintaining plant health by reducing physiological stress is the first recommendation for long-term control. Baited traps, ethanol-treated bolts, trap logs and trap trees of selected species can be used to monitor Xylosandrus species. Conventional pest control methods are mostly ineffective against Xylosandrus beetles because of the pests' broad host range and rapid spread. Due to challenges with conventional control, more innovative control approaches are being tested, such as the optimization of the push–pull strategy based on specific attractant and repellent combinations, or the use of insecticide-treated netting. Biological control based on the release of entomopathogenic and mycoparasitic fungi, as well as the use of antagonistic bacteria, has yielded promising results. However, these technologies still require validation in real field conditions. Overall, we suggest that management efforts should primarily focus on reducing plant stress and potentially be combined with a multi-faceted approach for controlling Xylosandrus damage. [ABSTRACT FROM AUTHOR]

Earwigs (Dermaptera), such as Forficula auricularia L., are important euryphagous predators for a wide variety of prey and can markedly influence the populations of orchard pests. Most previous studies on earwig feeding behaviour have not used adult beetles of the prey species; few researchers have focused on prey preference in earwigs. Some fragments of beetle exoskeleton and an earwig adult, Anisolabella marginalis (Dohrn), were found in the same cage, where adults of ambrosia beetle, Euwallacea interjectus (Blandford), were emerging from the logs of a fig tree infected with Ceratocystis canker (fig wilt disease). Thus, A. marginalis was suspected of being a predator of E. interjectus. To shed light on this issue, in the laboratory, we set up a test arena and observed and recorded behavioural interactions between A. marginalis and E. interjectus. E. interjectus was collected from the logs of fig trees and reared on an artificial diet, along with six different ambrosia beetle species, which were collected from a trap (baited with ethanol) and a fallen maple tree. A series of laboratory experiments demonstrated that A. marginalis is actually a predator of E. interjectus and other species of ambrosia beetle, indicating its a potential for use in effective pest control in the field. The predators frequently consume and tend to select their prey depending on prey size, rather than sex and beetle species. Furthermore, earwigs have alternative predatory strategies for dealing with seven different species, although they use their forceps to cut the body of most tested beetles. [ABSTRACT FROM AUTHOR]

The development of an efficient and cost‐effective method for monitoring animal populations or biodiversity is urgently needed, and invertebrate‐derived DNA (iDNA) may offer a promising tool for assessing the diversity and other ecological information of vertebrates. We studied the host species of a hematophagous leech (Haemadipsa japonica) in Yakushima by genetic barcoding and compared the results with those for mammal composition revealed by camera trapping. We analyzed 119 samples using two sets of primers by Sanger sequencing and one set of primer by next generation sequencing. The proportion of the samples that were successfully sequenced and identified to at least one species was 11.8–24.3%, depending on the three different methods. In all of these three methods, most of the samples were identified as sika deer (18/20, 6/15 and 16/29) or human (2/20, 7/15 and 21/29). The nonhuman mammal host species composition was significantly different from that estimated by camera trapping. Sika deer was the main host, which may be related with their high abundance, large body size and terrestriality. Ten samples included DNA derived from multiple species of vertebrates. This may be due to the contamination of human DNA, but we also found DNA from deer, Japanese macaque and a frog in the same samples, suggesting the mixture of the two meals in the gut of the leech. Using H. japonica‐derived iDNA would not be suitable to make an inventory of species, but it may be useful to collect genetic information on the targeted species, due to their high host selectivity. [ABSTRACT FROM AUTHOR]

In this study, we examined the genetic structures of the ambrosia fungus isolated from mycangia of the scolytine beetle, Xylosandrus germanus to understand their co-evolutionary relationships. We analyzed datasets of three ambrosia fungus loci (18S rDNA, 28S rDNA, and the β-tubulin gene) and a X. germanus locus dataset (cytochrome c oxidase subunit 1 ( COI) mitochondrial DNA). The ambrosia fungi were separated into three cultural morphptypes, and their haplotypes were distinguished by phylogenetic analysis on the basis of the three loci. The COI phylogenetic analysis revealed three distinct genetic lineages (clades A, B, and C) within X. germanus, each of which corresponded to specific ambrosia fungus cultural morphptypes. The fungal symbiont phylogeny was not concordant with that of the beetle. Our results suggest that X. germanus may be unable to exchange its mycangial fungi, but extraordinary horizontal transmission of symbiotic fungi between the beetle's lineages occurred at least once during the evolutionary history of this symbiosis. [ABSTRACT FROM AUTHOR]

Cytoplasmic incompatibility (CI)-inducing endosymbiotic bacteria, such as Wolbachia and Cardinium, have been well studied through field data and validations on the basis of numerical simulations. However, the analytically derived equilibrium frequency of multiple infections has not yet been determined, although the equilibrium for cases of single infection has been reported. In this study, we considered the difference equation for endosymbionts using three parameters: the probability of the failure of vertical transmission (), CI strength (), and the level of host inbreeding (). To analyze this model, we particularly focused on , i.e., the frequency of host individuals completely infected with all -bacterial strains in the population. , at the equilibrium state, was analytically calculated in the cases where and is any arbitrary value. We found that can be described using two parameters: and , which is identical to . has a larger value in a system with a smaller . In addition, determines the maximum number of strains that infect a single host. Our results revealed the following: i) three parameters can be reduced to a single parameter, i.e., and ii) the threshold of the maximum number of infections is defined by , which prevents additional invasions by endosymbionts. [ABSTRACT FROM AUTHOR]

Simple Summary: The sycamore lace bug (Corythucha ciliata Say, 1832) is one of the most abundant and widespread pests on plane trees (Platanus spp.) across the globe. The native range of the species is in North America, but it has been introduced to Europe (1964), South America (1985), Asia (1995), Australia (2006), and Africa (2014). To understand the genetic background behind this successful colonisation, we analysed a fragment (1356 bp) of the mitochondrial DNA. The 327 individuals revealed 17 haplotypes forming two separated groups. One group includes North American and Japanese individuals, while the other group comprises North American, European, and Asian individuals. We found a much higher genetic diversity in the native area (North America, 12 haplotypes) than in the invaded areas (Europe, five and Asia, four). The longer DNA fragment provided detailed information about the genetic structure of the species both in its native range and in the invaded areas, but the shorter DNA fragment could not provide a clear link between the genetic variation and the geographic origin. The sycamore lace bug (Corythucha ciliata Say, 1832) is of North American origin, but after its introduction to Europe (1964), South America (1985), Asia (1995), Australia (2006), and Africa (2014), it became an abundant and widespread pest on plane (Platanus spp.) trees. We analysed a 1356 bp long fragment of the mtDNA (COI gene) of 327 sycamore lace bug individuals from 38 geographic locations from Europe, Asia, and North America. Seventeen haplotypes (17 HTs) were detected. C. ciliata populations from North America exhibited higher haplotype diversity (12 HTs) than populations from Europe (6 HTs), Asia (4 HTs), or Japan (2 HTs). The haplotypes formed two haplogroups separated by at least seven mutation steps. One of these mutation steps includes HTs from North America and Japan. Another includes HTs from North America, Europe, and Asia. Haplotypes from Asia Minor, the Caucasus, and Central Asia are linked to haplotypes from Europe, while haplotypes found in Japan are linked to haplotypes found in North America only. The incorporation of published data from the GenBank into our dataset (altogether 517 individuals from 57 locations, but only 546 bp long fragment of the mtDNA) did not show any structure according to the geographic origin of the individuals. [ABSTRACT FROM AUTHOR]

The bark beetle Scolytogenes birosimensis Niijima is suspected to be involved in the decline of Pittosporum tobira (Thunb. ex Murray) Aiton in the coastal areas of Japan. We isolated fungi from adult S. birosimensis in nine different localities in Japan to assess their potential association and predict their contribution to the success of the beetle. Results from morphological identification of associated fungi showed that the beetle was associated with Fusarium solani and Candida spp. Furthermore, molecular analysis showed that F. solani was most closely related to the plant pathogenic fungus F. solani f. sp. mori. Fungal isolation from surface-sterilized, dissected beetles and scanning electron miscroscope (SEM) observation of the body surface suggested that the associated fungi were carded in the pits on the beetles' elytra. These findings contribute to the understanding of the relationships between S. birosimensis and its associated fungi. [ABSTRACT FROM AUTHOR]

We examined the genetic structure of populations of an ambrosia beetle, Xylosandvus brevis (Eichhoff) (Curculionidae: Scolytinae), to understand its colonization dynamics. We collected specimens from 20 sites in Japan and studied the genetic structure of these populations using portions of the mitochondrial cytochrome oxidase I gene (COl). A phylogenetic analysis showed three distinct lineages (clades A, B, and C) within X. brevis. Clade A had 65 haplotypes from all the populations, except for populations from Nagano (Chiisagata-gun) and the Ryukyu Islands (Ishigaki), whereas dade B had 14 haplotypes from nine populations (Yamagata, Saitama, Shimo-Minochi-gun, Chiisagatagun, Toyota, Watarai-gun, Wakayama, Tottori, and Kochi), and dade C had 6 haplotypes from the Ryukyu Islands (Ishigaki) population (and nowhere else). Nested dade phylogeographic analysis showed 65 dade A haplotypes and 14 dade B haplotypes geographically structured in two clades, respectively. A contact zone was identified in the Chubu and Tokai areas. Our results suggest that gene flow and individual movement of X. brevis between the Ryukyu Islands and the other three main islands of Japan has been rare, and X. brevis may be divided into two populations, eastern-central and northern-western, with little gene flow between the four areas of western Japan (Kinki, Chugoku, Shikoku, and Kyushu). [ABSTRACT FROM AUTHOR]

We examined the genetic structures of 13 Japanese populations of an ambrosia beetle, Xylosandrus germanus (Curculionidae: Scolytinae), to understand the effects of geographical barriers on the colonization dynamics of this species. The genetic structure was studied using portions of the mitochondrial cytochrome oxidase I ( COI) gene. A phylogenetic analysis revealed three distinct lineages (clades A, B and C) within X. germanus. Clade A contained 21 haplotypes from all 13 populations; whereas clade B contained eight haplotypes from Hokkaido (Sapporo and Furano), Iwate and Nagano populations; and clade C contained only a single a haplotype from the Hokkaido (Furano) population. In the analysis of molecular variance (amova), the greatest amount of genetic variation was detected between populations in Hokkaido and those in Honshu and other southern islands. Between these two groups of populations, all the values of the coefficient of gene differentiation were significantly larger than zero, except for the Hokkaido (Sapporo) versus Nagano comparison. Our results confirm that for X. germanus, gene flow has been interrupted between Hokkaido and Honshu since the last glacial maximum. [ABSTRACT FROM AUTHOR]

The dynamics of the fungal symbionts in the gallery system and the mycangia of the ambrosia beetle, Xylosandrus mutilatus, were studied in relation to its life history using both isolation experiments and scanning electron microscopy (SEM). In the galleries, Ambrosiella sp. was predominant during the larval stages but its relative dominance gradually decreased during the development of the larvae. In contrast, yeasts (mainly Candida sp.) and Paecilomyces sp. dominated continuously in the galleries after eclosion. Ambrosiella sp. was consistently stored in the mycangia in all adult stages, except in the teneral and overwintering adults when the other fungi were dominant. No fungal spores occurred in the mycangia of the adult beetles reared under aseptic conditions from the pupal stage, while only Ambrosiella sp. was stored in those reared from the teneral-adult stage. These results suggest that: (i) X mutilatus is associated with at least three fungal species, among which Ambrosiella sp. is the most essential food resource for development of the broods; (ii) immediately after eclosion, new female adults may take at least four associated fungal species, with no or incomplete selection, into their mycangia from the walls of the cradles; and (iii) conditions may well be produced in the mycangia of both matured and dispersing beetles whereby only the spores of Ambrosiella sp. can proliferate. [ABSTRACT FROM AUTHOR]