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The zeylanica group is one of the six species groups of the anthophilic genus Colocasiomyia de Meijere in the family Drosophilidae. In addition to two known species, five morphospecies have been recognized as members of this species group but left undescribed formally. In this study, species delimitation of these putatively new species was determined by barcoding of the mitochondrial COI (cytochrome c oxydase subunit I) gene and morphological comparison. Phylogenetic relationships within the genus Colocasiomyia were inferred by a cladistic analysis of 89 morphological characters. Based on the results of these analyses, we redefined the zeylanica species group and established two subgroups within it: the zeylanica subgroup comprised of C. zeylanica, C. nepalensis, C. pinangae sp. nov., C. besaris sp. nov. and C. luciphila sp. nov., and the oligochaeta subgroup of C. oligochaeta sp. nov. and C. grimaldii sp. nov. In addition, we briefly address the anthophilic habits of drosophilid flies using palm (Arecaceae) inflorescences, especially of the zeylanica group, compiling scattered collection records from the Oriental and Papuan regions.

The phylogeny of the Colocasiomyia cristata species group is reconstructed as a hypothesis, based on DNA sequences of two mitochondrial and six nuclear genes and 51 morphological characters. The resulting tree splits this species group into two clades, one of which corresponds to the colocasiae subgroup. Therefore, a new species subgroup named as the cristata subgroup is established for the other clade. Within the cristata subgroup, three subclades are recognized and each of them is defined as a species complex: the cristata complex composed of five species (including three new ones: C. kinabaluana sp. nov., C. kotana sp. nov. and C. matthewsi sp. nov.), the sabahana complex of two species (C. sabahana sp. nov. and C. sarawakana sp. nov.), and the xenalocasiae complex of five species (including C. sumatrana sp. nov. and C. leucocasiae sp. nov.). There are, however, three new species (C. ecornuta sp. nov., C. grandis sp. nov. and C. vieti sp. nov.) not assigned to any species complex. In addition, breeding habits are described for four cristata-subgroup species, each of which monopolizes its specific host plant. And, data of host-plant use are compiled for all species of the cristata group from records at various localities in the Oriental and Papuan regions. The evolution of host-plant selection and sharing modes is considered by mapping host-plant genera of each species on the phylogenetic tree resulting from the present study.

Flies of the Colocasiomyia toshiokai species group depend exclusively on inflorescences/infructescences of the aroid tribe Homalomeneae. The taxonomy and reproductive biology of this group is reviewed on the basis of data and samples collected from Southeast Asia. The species boundaries are determined by combining morphological analyses and molecular species delimitation based on sequences of the mitochondrial COI (cytochrome c oxidase subunit I) gene. For the phylogenetic classification within this species group, a cladistic analysis of all the member species is conducted based on 29 parsimony-informative, morphological characters. As a result, six species are recognised within the toshiokai group, including one new species, viz. C. toshiokai, C. xanthogaster, C. nigricauda, C. erythrocephala, C. heterodonta and C. rostrata sp. n. Various host plants are utilised by these species in different combinations at different localities: Some host plants are monopolized by a single species, while others are shared by two or three species. C. xanthogaster and C. heterodonta cohabit on the same host plant in West Java, breeding on spatially different parts of the spadix. There is a close synchrony between flower-visiting behaviour of flies and flowering events of host plants, which indicate an intimate pollination mutualism.

The risk of extreme events due to weather and climate change, such as winds of unprecedented magnitude, is predicted to increase throughout this century. Artificial ecosystems, such as coniferous plantation forests, can suffer irreversible deterioration due to even a slight change in environmental conditions. However, few studies have examined the effects of converting natural forests to plantations on their vulnerability to catastrophic winds. By modelling the 2004 windthrow event of Typhoon Songda in northern Japan using the random forest machine learning method, we answered two questions: do Abies plantation forests and natural mixed forests differ in their vulnerability to strong winds and how do winds, topography and forest structure affect their vulnerability. Our results show that Abies plantation forests are more vulnerable to catastrophic wind than natural mixed forests under most conditions. However, the windthrow process was common to both types of forests, and the behaviour of wind inside the forests may determine the windthrow probability. Future management options for adapting to climate change were proposed based on these findings, including modifications of plantation forest structure to reduce windthrow risk and reconversion of plantations to natural forests.

Rapid expansion of exotic bamboos has lowered species diversity in Japan's ecosystems by hampering native plant growth. The invasive potential of bamboo, facilitated by global warming, may also affect other countries with developing bamboo industries. We examined past (1975–1980) and recent (2012) distributions of major exotic bamboos (Phyllostachys edulis and P. bambusoides) in areas adjacent to 145 weather stations in central and northern Japan. Bamboo stands have been established at 17 sites along the latitudinal and altitudinal distributional limit during the last three decades. Ecological niche modeling indicated that temperature had a strong influence on bamboo distribution. Using mean annual temperature and sun radiation data, we reproduced bamboo distribution (accuracy = 0.93 and AUC (area under the receiver operating characteristic curve) = 0.92). These results infer that exotic bamboo distribution has shifted northward and upslope, in association with recent climate warming. Then, we simulated future climate data and projected the climate change impact on the potential habitat distribution of invasive bamboos under different temperature increases (i.e., 1.5°C, 2.0°C, 3.0°C, and 4.0°C) relative to the preindustrial period. Potential habitats in central and northern Japan were estimated to increase from 35% under the current climate (1980–2000) to 46%–48%, 51%–54%, 61%–67%, and 77%–83% under 1.5°C, 2.0°C, 3.0°C, and 4.0°C warming levels, respectively. These infer that the risk areas can increase by 1.3 times even under a 1.5°C scenario and expand by 2.3 times under a 4.0°C scenario. For sustainable ecosystem management, both mitigation and adaptation are necessary: bamboo planting must be carefully monitored in predicted potential habitats, which covers most of Japan.

Supply of non-timber Forest Products (NTFPs) is an important provisioning ecosystem service. It is often argued that forest conservation contributes to poverty alleviation through provisioning of NTFPs to the poor. However, implicit assumptions of the argument that NTFPs are more intensively utilized by poor who lack alternative subsistence options, and that NTFP supplies are limited by forest cover, have rarely been critically examined. This study investigated social and environmental factors affecting NTFP uses in rural areas of Borneo, using a land cover map and socio-economic dataset collected from 1596 households in 87 villages. The NTFPs examined were wild boars, sambar deer, wild fruits, firewood, wild vegetables, and wild mushrooms. To explain the variations in NTFP uses among households, four village and nine household characteristics were considered using generalized linear mixed models. We found that forest cover and collection pressure limit the use of some NTFPs, supporting the second assumption. On the other hand, the first assumption was supported only for firewood, and animals and wild fruits were more frequently used by wealthier households, contrary to this assumption. Other factors (education, age and sex of householder and agricultural activities) were also related to the use of one or more NTFPs. This study demonstrates the complexity of the process by which forest cover and other factors affect the ecosystem services people receive. Evaluation of ecosystem services is an important and urgent research subject today, but it is also necessary to pay attention to who receives the benefits, and who does not.

Facing potential coastal disasters such as storm surges, storm waves, and tsunamis, Japan has planned the construction of coastal structures such as seawalls or breakwaters along its coastal areas. However, some conflicts exist among the public whether such constructions should be undertaken or whether the natural coast should be conserved. This study uses a choice experiment to investigate opinions of coastal citizens about (1) the acceptable loss of coastal wildlife species as a tradeoff for seawalls; (2) the willingness to pay (WTP) for conservation of coastal wildlife as a compromise for disaster risk reduction; (3) the influence on popular preferences in coastal management of individual characteristics, such as frequency of visiting the sea and public recognition of disaster risk; and (4) civil trust in scientific information. The survey was conducted among 7496 respondents in municipalities around the Japanese coast. As a result, the acceptable loss of coastal wildlife species was 18.7 %. The marginal WTP for conserving the coastal wildlife was 680.95 JPY per percent in the number of species per capita. We found that people who frequently visit the sea preferred ecosystem conservation and disliked seawall construction, whereas people strongly recognizing disaster risks preferred seawall construction. Furthermore, we found that civil trust in scientific information affects civil preferences regarding coastal management. Our study indicates the need to reduce negative effects of coastal constructions on coastal ecosystems and to consider other options, such as ecosystem-based disaster risk reduction. It also indicates the social influences of raising public trust in scientific information to enable citizens to make better decisions regarding coastal management., 巨大防潮堤建設では生態系にも配慮を -全国沿岸地域7500人のアンケートで明らかに-. 京都大学プレスリリース. 2016-03-09.

A windthrow refers to the uprooting and overthrowing of trees by the wind. Typhoons are a major cause of windthrows in Japan and are predicted to intensify under global warming. This study aimed to estimate the impact of climate change on windthrows and evaluate possible adaptation measures for sustainable forest management. We incorporated Typhoon Songda (2004) simulation experiments under current and pseudo-global warming (2075–2099, RCP 8.5 scenario) conditions with windthrow modelling in four natural and four artificial (Abies sachalinensis, Pinaceae) forests of Hokkaido. Unexpectedly, pseudo-global warming conditions decreased windthrow probabilities compared with current conditions for both forest types, presumably because wind speeds of the simulated typhoon weakened in Japan’s high-latitude regions. Our results indicate that reconversion of artificial forests into natural forests largely decreased windthrow probability, providing a potential adaptation measure for improved forest management. To fully understand the range of climate-change effects on windthrow in Japan, future studies should use different climate scenarios and data from other typhoons, geographical regions, and forest types.

In recent decades, despite their value, coral reefs have been endangered and are swiftly declining because of land overuse, rising sea temperatures, and increasing ocean acidification. This study assesses the willingness to pay (WTP) for coral reef conservation in Japan. We conducted an online discrete choice experiment with 10,573 respondents. A latent class logit model framework was used, and three respondent classes were recognized. The first, consisting of about 60% of respondents, had the highest income level and a willingness to pay 326,036–414,391 JPY (100 JPY ≓ 1 USD) over a lifetime. Individuals in the second class, comprising approximately 30% of the respondents, were willing to pay 9792–12,262 JPY. The third class, consisting of approximately 10% of the respondents, comprised individuals not willing to pay any amount. We also evaluated the relative preferences of respondents for different conservation scenarios. The most preferred conservation target was total coral reef area, followed by scenic beauty, and species richness. We further estimate the effect of the types and amount of information on the WTP. Concise or detailed information with text and static images about coral reefs increased WTP by 11.7–19.1%. Providing video information, however, decreased the WTP by 4.9–7.0%.

Pine wilt disease (PWD) is one of the most serious conifer diseases, with further expansion expected under ongoing climate change. Sustainable forest management and effective pest control of pine forests therefore requires rigorous exploration of potential PWD risk areas under current and future climate conditions. To predict potential PWD risk areas in Japan, we constructed an inhomogeneous Poisson point process (IPP) model, which allows the use of strongly biased data. We examined both current and near-future climatic conditions (2026–2050, five general circulation model under two representative concentration pathways [RCPs]). Occurrence data were obtained on three different spatial scales (national, regional and local) along with eight bioclimatic variables. The resultant model was able to correct the data bias caused by using these three different data sources and showed high predictive power as follows: (1) potential risk areas will increase more than the current PWD distribution; (2) mean annual temperature will have the highest effect of the eight predictor variables; (3) high-risk areas will expand northwards and/or upwards in the near future, at a maximum of ca. +58.6% under RCP 8.5 and a minimum of ca. +15.9% under RCP 2.6 and low risk areas will decrease. The high-resolution PWD risk maps created with the IPP model will therefore aid future pest control and forest management strategies at local, regional, and national scales.

In contrast to the large number of studies addressing the effects of deforestation on insect diversity, few studies have focused on the recovery of diversity during forest restoration. In this study, we investigated the recovery, or chronosequential change, of butterfly species richness during forest restoration after cessation of swidden cultivation in a humid tropical rainforest region in Borneo. Through conducting censuses on butterflies at 21 study plots, placed at open habitats adjoining edges of forest stands that differed in elapsed years after cessation (

Pine wilt disease (PWD) constitutes a serious threat to pine forests. Since development depends on temperature and drought, there is a concern that future climate change could lead to the spread of PWD infections. We evaluated the risk of PWD in 21 susceptible Pinus species on a global scale. The MB index, which represents the sum of the difference between the mean monthly temperature and 15 when the mean monthly temperatures exceeds 15°C, was used to determine current and future regions vulnerable to PWD (MB ≥ 22). For future climate conditions, we compared the difference in PWD risks among four different representative concentration pathways (RCPs 2.6, 4.5, 6.0, and 8.5) and two time periods (2050s and 2070s). We also evaluated the impact of climate change on habitat suitability for each Pinus species using species distribution models. The findings were then integrated and the potential risk of PWD spread under climate change was discussed. Within the natural Pinus distribution area, southern parts of North America, Europe, and Asia were categorized as vulnerable regions (MB ≥ 22; 16% of the total Pinus distribution area). Representative provinces in which PWD has been reported at least once overlapped with the vulnerable regions. All RCP scenarios showed expansion of vulnerable regions in northern parts of Europe, Asia, and North America under future climate conditions. By the 2070s, under RCP 8.5, an estimated increase in the area of vulnerable regions to approximately 50% of the total Pinus distribution area was revealed. In addition, the habitat conditions of a large portion of the Pinus distribution areas in Europe and Asia were deemed unsuitable by the 2070s under RCP 8.5. Approximately 40% of these regions overlapped with regions deemed vulnerable to PWD, suggesting that Pinus forests in these areas are at risk of serious damage due to habitat shifts and spread of PWD.

The phylogeny of Colocasiomyia (Drosophilidae) is analysed using data for 70 morphological characters, many of which are re-evaluated from or added to those used previously, for an expanded taxon sample of 24 Colocasiomyia ingroup species. A special focus is put on three species, of which two have remained unresolved for their relationships to other Colocasiomyia species, and the other is a newly discovered species. The analysis results in a single, most parsimonious cladogram, in which a clade comprising the three focal species is recognized along with other clades recovered for the known species groups of Colocasiomyia. Based on this, a new species group—the gigantea group—is established, including Colocasiomyia gigantea (Okada), C. rhaphidophorae Gao & Toda, n.sp. and C. scindapsae Fartyal & Toda, n.sp. These species of the gigantea group breed on inflorescences/infructescences of the subfamily Monsteroideae (Araceae) exceptionally among Colocasiomyia species, most of which use plants of the subfamily Aroideae as their hosts. Colocasiomyia gigantea uses Epipremnum pinnatum (L.) Engler, C. rhaphidophorae uses Rhaphidophora hookeri Schott and C. scindapsae uses Scindapsus coriaceus Engler as their hosts. The host plants of the gigantea group are epiphytes and differ in the structure of spadix and the fruiting process from those of the Aroideae. To understand how the species of the gigantea group adapt to properties of their host plants, their reproductive ecology—most intensively that of C. gigantea—is investigated. The lifecycle of C. gigantea is characterized by its relatively slow embryonic development (taking approximately 6 days), the very long duration of the full-grown first instar within the egg capsule (approximately three months) until dehiscence of host infructescence, and its relatively fast larval and pupal development (taking approximately 11 or 12 days). Some morphological adaptations and the reproductive strategy in terms of ‘egg size vs. number’ trade-off are discussed in relation to their reproductive habits and peculiar lifecycles.

We conducted phylogenetic analyses and an estimation of coalescence times for East Asian strains of HTLV-1. Phylogenetic analyses showed that the following three lineages exist in Japan: "JPN", primarily com-prising Japanese isolates; "EAS", comprising Japanese and two Chinese isolates, of which one originated fromChengdu and the other from Fujian; and "GLB1", comprising isolates from various locations worldwide, includinga few Japanese isolates. It was estimated that the JPN and EAS lineages originated as independent lineages approx-imately 3,900 and 6,000 years ago, respectively. Based on archaeological findings, the "Out of Sunda" hypothesiswas recently proposed to clarify the source of the Jomon (early neolithic) cultures of Japan. According to thishypothesis, it is suggested that the arrival of neolithic people in Japan began approximately 10,000 years ago, witha second wave of immigrants arriving between 6,000 and 4,000 years ago, peaking at around 4,000 years ago. Esti-mated coalescence times of the EAS and JPN lineages place the origins of these lineages within this 6,000-4,000 year period, suggesting that HTLV-1 was introduced to Japan by neolithic immigrants, not Paleo-Mongoloids.Moreover, our data suggest that the other minor lineage, GLB1, may have been introduced to Japan by Africansaccompanying European traders several centuries ago, during or after "The Age of Discovery." Thus, the resultsof this study greatly increase our understanding of the origins and current distribution of HTLV-1 lineages in Japanand provide further insights into the ethno-epidemiology of HTLV-1., Tropical Medicine and Health, 40(4), pp.117-124; 2013

Whereas many studies have addressed the effects of deforestation on biodiversity, few have focused on the recovery of diversity during reforestation. This study aimed at evaluating the recovery of, or chronosequential changes in, the biodiversity in the fallows (i.e., secondary vegetation or forests that form during the resting periods following harvest in shifting cultivation) of a tropical rainforest region in Borneo. We also aimed at determining the impacts of forest fragmentation and other land-use changes on biodiversity.