Old-growth forests host a rich diversity of invertebrate assemblages. Among them, saproxylic insects play a fundamental role in the nutrient cycle and ecosystem functioning. In these environments, coevolution between insect and plants have reached a stable equilibrium over millions of years. These delicate ecosystems are threatened mainly by habitat loss and fragmentation, and to date, they have to face the new \"plastic threat.\" Plastics are widespread in all biomes and ecosystems accumulating throughout the years due to their low degradation rate. Once accumulated, large pieces of plastics can be degraded into smaller particles, the latter representing a great threat to biodiversity and ecosystem health, producing detrimental effects on biota. Since the effects of plastics on terrestrial systems remain largely unexplored, this study aimed at contributing to increasing the knowledge on the interaction between plastics and terrestrial biota. We put our emphasis on the novel and broad topic of plastic degradation by saproxylic beetle larvae, describing how they fragmented macroplastics into microplastics. To investigate whether saproxylic cetonid larvae could degrade expanded polystyrene, we performed an experiment. Thus, we put larvae collected in the field in an expanded polystyrene box. We observed that larvae dug in the thickness of the box fragmenting macroplastics into microplastics and producing a total of 3441 particles. Then, we removed the larvae from the EPS box and isolated them in glass jars filled with natural substrate. The substrate was checked for EPS microplastics previously ingested and now egested by larvae. Additionally, we pointed out that plastics remained attached to cetonid larvae setae, with a mean number of 30.7 ± 12.5 items. Although preliminary, our results highlighted that microplastics attached to saproxylic cetonid larvae might be transported into habitats and transferred along the food web. In conclusion, plastic pollution might affect vulnerable species and ecosystem services representing a risk also for human health.

Rotting wood is inhabited by a large diversity of bacteria, fungi, and insects with complex environmental relationships. The aim of this work was to study the composition of the microbiota (bacteria and fungi) in decaying wood from a northwest Spanish forest as a source of industrially relevant microorganisms. The analyzed forest is situated in a well-defined biogeographic area combining Mediterranean and temperate macrobioclimates. Bacterial diversity, determined by metagenome analyses, was higher than fungal heterogeneity. However, a total of 194 different cultivable bacterial isolates (mainly Bacillaceae, Streptomycetaceae, Paenibacillaceae, and Microbacteriaceae) were obtained, in contrast to 343 fungal strains (mainly Aspergillaceae, Hypocreaceae, and Coniochaetaceae). Isolates traditionally known as secondary metabolite producers, such as Actinobacteria and members of the Penicillium genus, were screened for their antimicrobial activity by the detection of antibiotic biosynthetic clusters and competitive bioassays against fungi involved in wood decay. In addition, the ability of Penicillium isolates to degrade cellulose and release ferulic acid from wood was also examined. These results present decaying wood as an ecologically rich niche and a promising source of biotechnologically interesting microorganisms.

Five yeast strains were isolated from the gut of the groundbeetle Pterostichus gebleri and rotting wood, which were collected from two different localities in China. These strains were identified as representing two novel species of the genus Blastobotrys through comparison of sequences in the D1/D2 domains of the LSU rRNA gene and other taxonomic characteristics. Blastobotrys baotianmanensis sp. nov. produces two to three spherical ascospores per ascus, and is most closely related to the type strains of B. elegans, B. capitulata, B. arbuscula, and an undescribed species represented by strain BG02-7-20-006A-3-1. Blastobotrys baotianmanensis sp. nov. differed from these strains by 3.6-8.4 % divergence (21-46 substitutions and 0-4 gaps) in the D1/D2 sequences. Blastobotrys xishuangbannaensis f.a., sp. nov. is closely related to B. nivea, B. elegans and B. aristata but the formation of ascospores was not observed on various sporulation media, and it differed from its relatives by 6.2-8.5 % divergence (34-43 substitutions and 2-6 gaps) in the D1/D2 sequences. The holotype of Blastobotrys baotianmanensis sp. nov. is NYNU 1581 and the holotype of Blastobotrys xishuangbannaensis f.a., sp. nov. is NYNU 181030.

Cellulosic biomass degradation still needs to be paid more attentions as bioenergy is the most likely to replace fossil energy in the future, and more evaluable cellulolytic bacteria isolation will lay a foundation for this filed. Qinling Mountains have unique biodiversity, acting as promising source of cellulose-degrading bacteria exhibiting noteworthy properties. Therefore, the aim of this work was to find potential cellulolytic bacteria and verify the possibility of the cloning of cellulases from the selected powerful bacteria.
In present study, 55 potential cellulolytic bacteria were screened and identified from the rotten wood of Qinling Mountains. Based on the investigation of cellulase activities and degradation effect on different cellulose substrates, Bacillus methylotrophicus 1EJ7, Bacillus subtilis 1AJ3 and Bacillus subtilis 3BJ4 were further applied to hydrolyze wheat straw, corn stover and switchgrass, and the results suggested that B. methylotrophicus 1EJ7 was the most preponderant bacterium, and which also indicated that Bacillus was the main cellulolytic bacteria in rotten wood. Furthermore, scanning electron microscopy (SEM) and X-ray diffraction analysis of micromorphology and crystallinity of wheat straw also verified the significant hydrolyzation. With ascertaining the target sequence of cellulase β-glucosidase (243 aa) and endoglucanase (499 aa) were successfully heterogeneously cloned and expressed from B. methylotrophicus 1EJ7, and which performed a good effect on cellulose degradation with enzyme activity of 1670.15 ± 18.94 U/mL and 0.130 ± 0.002 U/mL, respectively. In addition, based on analysis of amino acid sequence, it found that β-glucosidase were belonged to GH16 family, and endoglucanase was composed of GH5 family catalytic domain and a carbohydrate-binding module of CBM3 family.
Based on the screening, identification and cellulose degradation effect evaluation of cellulolytic bacteria from rotten wood of Qinling Mountains, it found that Bacillus were the predominant species among the isolated strains, and B. methylotrophicus 1EJ7 performed best on cellulose degradation. Meanwhile, the β-glucosidase and endoglucanase were successfully cloned and expressed from B. methylotrophicus for the first time, which provided new materials of both strain and the recombinant enzymes for the study of cellulose degradation and its application in industry.

During studies on the yeast communities associated with rotting wood in the Xishuangbanna Tropical Rainforest in PR China, four novel yeast strains were found. Phylogenetic analysis based on the concatenated sequences of the D1/D2 domains of the large subunit rRNA gene and the ITS regions showed that these strains represented two novel species in the Candida albicans/Lodderomyces clade. The novel species, represented by strains NYNU 17948 and NYNU 17981, formed a clade with Candida maltosa and Candida baotianmanensis, with 1-1.8% sequence divergence in the D1/D2 domains and 8.9-10% sequence divergence in the ITS regions. The other novel species, represented by NYNU 17105 and NYNU 17763, is most closely related to Candida blackwelliae with 0.7 % sequence divergence in the D1/D2 domains and 6.9 % sequence divergence in the ITS regions. The two novel species could be distinguished from their closest described species in terms of physiological traits. The two novel species are described as Candida yunnanensis sp. nov. (holotype NYNU 17948) and Candida parablackwelliae sp. nov. (holotype NYNU 17763).

Five strains, NUNU 16637, NYNU 16645, NYNU 1673, NYNU 1680 and NYNU 1689, of a novel ascomycetous yeast were isolated from the Xishuangbanna tropical rainforest, Yunnan Province, PR China. The five strains shared identical sequences in both of the D1/D2 domains of the large subunit rRNA gene and the internal transcribed spacer (ITS) regions. Sequence analysis showed that they represent undescribed yeast species belonging to the genus Wickerhamomyces. They differed from their closest known species, Wickerhamomyces xylosivorus NBRC 111553T, by 3.4 % sequence divergence (14 substitutions and six gaps out of 584 bp) in the D1/D2 domains and by 9.6 % sequence divergence (28 substitutions and 24 gaps over 543 bp) in the ITS regions, respectively. The five strains of novel species reproduced asexually; no sexual reproduction could be found. In contrast to W. xylosivorus, the novel yeast species were able to assimilate l-arabinose, inulin, soluble starch, d-mannitol and citrate, and unable to assimilate trehalose, raffinose, 5-keto-d-gluconate, d-gluconate, ethanol, ethylamine and cadaverine. Growth was observed at 35 °C. The name Wickerhamomyces menglaensis f.a., sp. nov. is proposed to accommodate these strains, with NYNU 1673 as the holotype.

Three strains of a novel basidiomycetous yeast were isolated from the Xishuangbanna Tropical Rainforest, Yunnan Province, PR China. Sequence analysis of the D1/D2 domains of the large subunit (LSU) rRNA gene and the internal transcribed spacer (ITS) regions indicated that the novel species represents a member of the genus Vanrija. It differed from the most closely related known species, Vanrija albida CBS 2839T, by 1.5 % sequence divergence (seven substitutions and two gaps out of 597 bp) in the D1/D2 domains and by 7.4 % sequence divergence (17 substitutions and 20 gaps over 495 bp) in the ITS regions, respectively. The three strains of the novel species reproduced asexually, and no mating could be found. In contrast to V. albida, the novel yeast species was able to assimilate d-glucosamine, inulin, erythritol and galactitol and unable to assimilate raffinose. The name Vanrija jinghongensis sp. nov. is proposed to accommodate these strains, with NYNU 17910T (=CICC 33269=CBS 15229) as the type strain.

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.

THIS STUDY DESCRIBES AND ILLUSTRATES THE LARVAE AND PUPAE OF TWO NORTH AMERICAN DARKLING BEETLES (COLEOPTERA: Tenebrionidae) in the subfamily Stenochiinae, Glyptotus cribratus LeConte from the southeastern United States, and Cibdelis blaschkei Mannerheim from California. Both species inhabit forested regions where adults and larvae occur in soft rotten dry wood of dead branches on living trees or in sections recently fallen from them. Species identity was confirmed by rearing of adults and pupae and the discovery of both in pupal cells with associated exuvia. Specimen label data and notes on habitats are provided. Antipredator defense structures and behaviour are noted for larvae and pupae of both species.