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The larvae of Japanese rhinoceros beetle, Trypoxylus dichotomus, feed on dead plant material in forest soils that are derived from fallen leaves broken down by basidiomycete fungi. Our previous work provided an understanding of the degradation of polysaccharides in dead plant material by T. dichotomus larvae and reported the complexity of the physicochemical and biochemical environment of the larval gut. Here, we examined ten divisions of the digestive tract of T. dichotomus larvae for physicochemical and biochemical conditions to elucidate site‐specifically functional properties along the tract. The distribution of potassium ions, pH, and acetic acid differed markedly along the length of the digestive tract with the potassium ion concentration profile closely reflecting that of pH along the length of the digestive tract. Distinct physicochemical environments were maintained in the digestive tract along with site‐specific polysaccharide degradation. Based on these findings, we suggest that there are metabolic relationships between the activities of the enzymes involved in polysaccharide degradation, the presence of intermediate metabolites and location along the digestive tract. Furthermore, we revealed that the anterior region of the gut plays an important role in the degradation of polysaccharides in the digestive tract of T. dichotomus larvae.

We investigated the cannibalism and its association with cannibalistic grooming in Reticulitermes speratus (Kolbe), first by observing workers’ cannibalistic behavior against workers artificially wounded on different body parts. Almost all the wounded thoraces and abdomina were eaten, while in some of the abdomen-wounded individuals, nestmates’ cannibalism extended from the abdomen to the thorax, and thorax was cannibalistically attacked in all the abdomen-wounded individuals. In thorax-wounded individuals cannibalistic damage mostly extended from the thorax to the abdomen to a lesser degree. In the assessments of the frequencies and durations of the cannibalistic groomings toward different body parts, the wounded individuals, upon being groomed, occasionally exhibited vibrational behavior, and its frequencies upon the groomings toward wounded body parts were significantly higher than those toward non-wounded body parts. Vibration significantly reduced the duration of cannibalistic grooming on the wounded head and abdomen, while it reduced the grooming frequency and did not reduce the duration of grooming on wounded thorax. These results suggest that the vibration serves as a vital sign or death-negative factor in death recognition. A feeding experiment with workers’ cuticular hydrocarbon extract showed that it did not promote cannibalistic behavior. A feeding experiment with filter papers impregnated with different body part extracts showed that all the extracts exhibited phagostimulant activity, with workers’ body extracts resulting in significantly higher quantity of consumption than in soldiers’ except abdomen. Further assay revealed a stronger activity of labial gland compared to the labial gland-removed thorax, suggesting the key role of labial gland in cannibalism.

Two rove beetle species in the tribe Termitohospitini (Coleoptera: Staphylinidae: Aleocharinae), Sinophilus yukoae MaruyaMa et Iwata, 2002 and Japanophilus hojoi MaruyaMa et Iwata, 2002, are termitophiles associated with the Formosan subterranean termite, Coptotermes formosanus ShIrakI, 1909 (Blattodea, Rhinotermitidae). Sinophilus yukoae was recorded from the Nansei Archipelago (Iheya-jima, Ishigaki-jima, and Iriomote-jima Islands), and J. hojoi was reported from the Tokara Archipelago (Nakano-shima and Suwanose-jima Islands) and Yaku-shima Island in the original descriptions (MaruyaMa & Iwata, 2002). Subsequently, both beetles were collected in coastal regions of Wakayama Prefecture, Central Japan (MaruyaMa et al., 2012). We renew the distributional ranges of the two beetles here.

Members of the termitophilous subtribe Termitozyrina (Aleocharinae: Lomechusini) associated with Hodotermopsis sjostedti are taxonomically treated. The genera Hodotermophilus Naomi & Terayama and Termophidoholus Naomi & Hirono, and each type species (monotypic) are redescribed. Termophidoholus formosanus, originally described from Taiwan, and its host termite H. sjostedti are newly recorded from Laos. Yakuus iwatai Kanao & Maruyama gen. & sp. nov. and H. gloriosus were collected sympatrically in the same nests in Yaku-shima, Japan. All of the above species, belonging to the three genera, share the presence of a batch of spurs at the tibial apex of fore and mid legs. Habitus photographs and illustrations of diagnostic features are provided for these species, and their phylogenetic relationships are discussed based on morphological similarities and the extant distribution of the host termite species.

We examined the nematode fauna associated with a species of bark beetle, Dryocoetes uniseriatus Eggers, as part of a biodiversity survey of forest beetle-associated nematodes. Collections were made in a pine stand at an experimental forest station in Ibaraki, Japan, from April to July of 2011; we examined the nematode association in 273 insects collected during this time. In total, 68% of the insects were associated with at least one species of nematode. Six species of nematodes, including two phoretic microbe feeders (Bursaphelenchus rainulfi BraaschBurgermeister and Micoletzkya sp.), one insect parasite and nematode predator (Devibursaphelenchus cf. eproctatus), one insect parasite (Contortylenchus sp.), one insect parasite and potential microbe feeder (unidentified rhabditid parasite), and one potential insect parasite and fungal feeder (B. sinensis) were recovered from the beetles. D. cf. eproctatus was enclosed in nematangia on the backsides of the elytra, B. rainulfi was isolated from the backsides of the elytra or enclosed in nematangia, Micoletzkya sp. was isolated from under the elytra, Contortylenchus sp. and a rhabditid parasite parasitized the body cavity, and B. sinensis was found in the digestive tract of the insect. The association patterns of the nematode species varied seasonally, although definitive interactions among species (e.g., segregation, competition) were not observed.

Beetles of the family Passalidae (Coleoptera: Scarabaeoidea) are termed subsocial. The insects inhabit rotten wood as family groups consisting of the parents and their offspring. The Japanese species Cylindrocaulus patalis has the lowest fecundity among passalids because siblicide occurs among the first-instar larvae; accordingly, parental care toward the survived larva is the highest among Passalidae. To clarify the nutritional relationships between the parents and their offspring, we investigated their ability to digest three types of polysaccharides that are components of wood (cellulose and β-1,4-xylan) and fungal cell walls (β-1,3-glucan). Although carboxymethyl-cellulase activity was barely detectable, β-xylosidase, β-glucosidase, β-1,4-xylanase and β-1,3-glucanase activities were clearly detected in both adults and larvae. Because the activities of enzymes that digest β-1,3-glucan were much higher than those for degrading β-1,4-xylan, in both adults and larvae, it is concluded that they are mainly fungivorous. Furthermore, these digestive enzymatic activities in second- and third-instar larvae were much lower than they were in adults. Although all larval instars grew rapidly when fed chewed wood by their parents, larvae ceased growing and died when fed only artificially ground wood meals. We conclude that the larvae are assumed to be provided with chewed predigested wood in which β-1,3-glucan is degraded by parental enzymes.

Estimating the genetic structure of a population is important for the conservation and management of wildlife. In the present study, our aim was to estimate the genetic structure of the brown bear (Ursus arctos) population in eastern Hokkaido by performing a Bayesian clustering analysis. To accomplish this goal, we used 15 microsatellites to generate genotypic data from tissue samples collected from 646 bears between 1996 and 2008. Using this genotypic data and the geographic locations where the bears were captured, GENELAND analysis detected six subpopulations. Based on the genotypic data, the STRUCTURE analysis revealed three subpopulations. As inferred from the GENELAND analysis, the core zones of the subpopulations (G-a through G-f) were located in the Shiranuka Hills (G-a), the northern area of the Shiranuka Hills (G-b), the eastern slope of the Daisetsuzan Mountains (G-c), the northern slope of the Akan Mountain Range (G-d), the Shiretoko Peninsula (G-e), and Akkeshi District (G-f). The STRUCTURE analysis indicated that G-b and G-d were influenced by gene flow from other subpopulations. National routes, towns, and farm fields were considered to have formed the distribution boundaries among the subpopulations. A high level of genetic differentiation was not observed among the six subpopulations, with the exception of G-f (Fst = 1.35–0.176, Ds = 0.246–0.349), which showed a geographically discontinuous distribution. We suggest that the loss of forest areas through future regional development and road building should be avoided to facilitate gene flow in brown bears in Hokkaido.

Male brown bears (Ursus arctos) generally disperse over longer distances than females, which have conservative habitats around their natal areas. Our previous study indicated that the distributions of mitochondrial DNA (mtDNA) subhaplotypes in females were allopatric in the southern Akan—Shiranuka region of eastern Hokkaido. Dispersal of males from their natal area to another natal area is easily detected from the allopatric distributions of two of the mtDNA subhaplotypes of female bears (HB02a and HB13b). Here, to investigate the effectiveness of gene flow and dispersal of male bears between two natal areas, we assessed the genetic diversity and kinship of 132 brown bears from 1996 and 2008 in this area by analyzing the polymorphisms of mtDNA and microsatellite DNA. Parentage testing revealed that there were 48 potential father—offspring pairs, nine potential mother—offspring pairs, and four potential parent—offspring trios. Among 33 of the 48 father—offspring pairs, the mtDNA subhaplotypes dif...

We examined 24 microsatellite markers to select those most suitable for individual identification and parentage tests of brown bears (Ursus arctos) based on statistical parameters and experimental error using liver samples (38 issues) from nuisance bears killed in the Akan–Shiranuka Region, eastern Hokkaido, Japan from 1996 to 2006. We found seven microsatellite markers suitable for identifying individuals (G1A, G10B, G10L, UarMU5, UarMU23, UarMU50, and UarMU51; probability of identity P id = 3.17 × 10−7; probability of identity of sibs P id-sib = 2.23 × 10−3), 12 microsatellite markers suitable for parentage testing when one parent is known [G1A, G1D, G10B, G10L, G10P, UarMU5, UarMU23, UarMU50, UarMU51, UarMU59, UarMU61, and UarMU64; probability of excluding one parent (PE I = 0.9991)], and 15 microsatellite markers for parentage testing when neither parents are known [three markers added to the above: G10M, G10X, and UarMU9; probability of excluding both parents (PE II = 0.9869)].

The cerambycid borers Callidiellum rufipenne (Motschulsky) and Semanotus bifasciatus (Motschulsky) infest coniferous logs in Japan, with the latter distributed in the north and at high altitudes, where both species occur sympatrically. Semanotus bifas- ciatus adults were active at low temperatures and very active after sunset, and less active but never inactive in the daytime, whereas C. rufipenne adults were usually active at high temperatures and almost only in the daytime. At an almost constant temperature, C. rufipenne adults were almost inactive at night, whereas S. bifasciatus adults showed only an obscure decline in activity in the morn- ing. Of a horizontal log, the upper surface tended to be drier and lower surface wetter, and C. rufipenne larvae grew large if they were in the upper part of a log, whereas S. bifasciatus larvae grew large if in the lower part. Thus, the coexistence of these two spe- cies can be ascribed to two major segregation factors: adult segregation based on temperature and sunshine, and larval segregation associated with the moisture content of the wood.

Larval behavior of Dinoptera minuta (Gebler) (Coleoptera: Cerambycidae) was observed in natural and experimental situations. In dead twigs of Cornus controversa, the larvae were found only under the rotten, fragile bark, and were observed to subsist on inner phloem, whereas xylem portions were never eaten. Mature larvae crept under the bark with their dorsum facing the xylem side. Meanwhile, as the outer phloem was broken, mature larvae left the dead twig and burrowed into the soil beneath. In the laboratory, movement of the larvae from the twigs to the soil took place from late August to late December. Most of the mature larvae transferred to test tubes filled with soil were observed to stay at certain positions in the soil at an average depth of 4.3 cm. A comparison of digestive tracts of an immature feeding larva and a mature moving larva revealed little change of total tract length, marked atrophy of the midgut of the latter, little change of hindgut, and a color change from ocherous to clear...

We observed the mating behavior of Monochamus saltuarius (Cerambycidae: Lamiinae) and confirmed the following behavioral actions. The male reacted to the female with his antennae or tarsi, the male dashed to the female and mounted her back. Copulation consisted of three phases: First, while bending at the abdomen, the male inserted his penis into the female's genitalia, second, the male is motionless with the females genitalia being pulled out from her abdomen by the males penis, outside of both body cavities, finally, the male tries to pull out his penis from the female genitalia. The copulation was shown to take place mostly for one and a half minutes, with a significant tendency to be slightly shortened as the pair progressed from the first through the third copulation. The violent fight between two males took place in the presence of a female and sometimes she changed her mate. The male did not differentiate between dead and live females, because the male mounted dead females as same as live them.

The nutrient intake of the third instar larvae of Anomala cuprea (Ac) and Protaetia orientalis submarmorea (Pos) (Coleoptera: Scarabaeidae) from a mixture of cow dung and wood chips of two wood species (Cryptomeria japonica and Quercus mongolica), was assayed by the stable isotope technique. The values of δ15N and δ13C (deviations of 15N/14N and 13C/12C from the standard materials) were measured in the following samples: (1) the integument plus the head of the 3rd instar larvae of both species reared in 1999 autumn fed with a mixture of cow dung and wood chips or with leaf mold, (2) cow dung, (3) wood chips, and (4) leaf mold as the larval food before onset of rearing. The δ values of the bodies of larvae fed with leaf mold differed with the beetle species. The δ15N values of the larval bodies of both species fed with the mixture were close to those of cow dung, whereas the δ13C values were in between those of cow dung and wood chips. Therefore, both species were presumed to obtain almost all their nitrogen from cow dung, and their carbon from both cow dung and wood chips.

The termitophilous tribe Termitohospitini was discovered in Japan. Sinophilus yukoaesp.nov. and Japanophilus hojoigen.nov., sp.nov. are described from specimens collected in Nansei-shotô. The genus Sinophilus is redefined. These species are the first-discovered inquilines of Coptotermes formosanus Shiraki in Japan. This suggests that C. formosanus is native to Japan rather than an introduced species, as previously believed.

Members of the genus Termitaria are entomogenous exoparasitic deuteromycetes growing on the exoskeleton of various species of termites. Distinguished by sporodochial surface color, three types of Termitaria were found from six termite species of four genera from various localities in Japan: Black-type, White-type and Intermediate-type. Molecular phylogenetic analysis focusing on the genetic lineage of Termitaria, using sequences of the nucleotide 18S rRNA gene, suggested that these three types were actually different species. The resultant phylogenetic tree of Termitaria did not show any contradiction to the topology known in the host phylogeny. This suggests that there is a parallel cladogenesis between the hosts and fungi, and that there has been scarcely any detectable horizontal transmission of fungi between the host species. The only exception was found in Yakushima Is., where Black-type may have changed its host from Hodotermopsis japonica to Reticulitermes speratus.

White plastic insect traps (manufactured by Sankei Chemical Co., Ltd.) equipped with four chemicals with floral scents, namely, benzyl acetate, methyl benzoate, methyl phenylacetate and linalool, were set from June 28 to August 9, 1996. The traps were placed in a Japanese beech (Fagus creata) forest, Minakami, Gunma Prefecture, Central Japan, and trapped longicorn beetles were collected weekly. The greatest number of species and individuals belonged to the subfamily Lepturinae dominated by the genusPidonia. No significant differences were observed in the performances of the above four chemicals in either the total number of species or of individuals. However, more Lamiinae species were captured in the traps with methyl phenylacetate, than in those with methyl benzoate.

Beetle samples captured by traps were compared with those captured manually on flowers in a beech forest in Central Japan. Plastic traps (Sankei Chemical Co., Ltd.) equipped with benzyl acetate were set up from the 2nd of June to the 8th of September 1994, and all beetles captured were collected every week. Beetles were also captured on wild flowers blooming along the forest road. The traps captured 21,650 individuals of 169 species in 37 families. On the other hand, 971 individuals of 77 species in 19 families were captured on the flowers. All of the families and 57 (74%) species of the beetles captured on the flowers were also captured by the traps; all of the species with more than five individuals captured on the flowers were also trapped, except for one species. The present trap system is considered to be useful for faunal monitoring of flower-visiting Coleoptera, because the beetle fauna found on wild flowers was virtually covered by the trap capture.

Beetle samples were compared between catches by traps and those on flowers in a Japanese beech (Fagus crenata Blume) forest, in Minakami, Gunma Prefecture, Japan. White plastic traps (Sankei Chemical Co., Ltd.) equipped with benzyl acetate were set out for a month from July 23 to August 23, 1993, and all beetles captured were collected every six days. During six days from August 10 to August 16, beetles were captured with traps and on wild flowers (Aruncus sylvester Kostel andAngelica polyclada Franch) at three hour intervals. Over the month, the traps captured 1,677 individuals of 73 species of 20 families, which included 16 (89%) species captured on flowers in the six-day period. Over the six days, the traps captured 327 individuals of 21 species of 12 families, compared with 685 individuals of 18 species of 5 families on the flowers; all of the families and nine (50%) species of beetles taken on the flowers were also captured by the traps; all of the species with more than five individuals captured on the flowers were also trapped. This suggests that capture by traps might sufficiently cover the beetle fauna on flowers. The number of species and individuals, as well as their changing patterns, however, varied more irregularly during the six-day period with the traps than with those on the flowers.

Recent progress in molecular ecological methods has enabled us to study genetic differentiation among populations. By elucidating the genetic structure, we can trace the history of populations and to infer ongoing patterns of migration. In this chapter, we review the population structure of the pine sawyer Monochamus alternatus detected by microsatellite markers and mitochondrial DNA. First, the process of population expansion is inferred from the genetic structure determined from populations of Japan, China and Taiwan populations by mitochondrial DNA and microsatellite markers. Secondly, microsatellite markers are used to show the pine sawyers’ dispersal route in the past in the northern part of Honshu Island, Japan, which is the frontier of the area damaged by pine wilt disease. Finally we discuss further subjects in studies of the sawyers’ dispersals.

In anAbies homolepis Sieb. et Zucc. forest at Matsumoto, Nagano Pref., cumulative damage byXylotrechus villioni (Villard) (Coleoptera: Cerambycidae) was observed on tree branches. Of the 14 major branches in one sample tree, six had cumulative damage by boring larvae, of which 3 had been bored by multiple larvae. No adult emergence holes were found on the whole tree, suggesting very low survivorship from boring larva to emerging adult. Galleries made by single larvae were often observed to be terminated by a depression apparently carved by a picid woodpecker, suggesting that they are important predators of the cerambycid. The manner of cicatrix formation with phloem tissue over the larval gallery in anAbies veitchii Lindl. branch at Mt. Fuji, Yamanashi Pref. is presented.