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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.

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.

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.

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.