Hironori Toyama

A new subfamily classification of the leguminosae based on a taxonomically comprehensive phylogeny

The classification of the legume family proposed here addresses the long-known non-monophyly of the traditionally recognised subfamily Caesalpinioideae, by recognising six robustly supported monophyletic subfamilies. This new classification uses as its framework the most comprehensive phylogenetic analyses of legumes to date, based on plastid matK gene sequences, and including near-complete sampling of genera (698 of the currently recognised 765 genera) and ca. 20% (3696) of known species. The matK gene region has been the most widely sequenced across the legumes, and in most legume lineages, this gene region is sufficiently variable to yield well-supported clades. This analysis resolves the same major clades as in other phylogenies of whole plastid and nuclear gene sets (with much sparser taxon sampling). Our analysis improves upon previous studies that have used large phylogenies of the Leguminosae for addressing evolutionary questions, because it maximises generic sampling and provides a phylogenetic tree that is based on a fully curated set of sequences that are vouchered and taxonomically validated. The phylogenetic trees obtained and the underlying data are available to browse and download, facilitating subsequent analyses that require evolutionary trees. Here we propose a new community-endorsed classification of the family that reflects the phylogenetic structure that is consistently resolved and recognises six subfamilies in Leguminosae: a recircumscribed Caesalpinioideae DC., Cercidoideae Legume Phylogeny Working Group (stat. nov.), Detarioideae Burmeist., Dialioideae Legume Phylogeny Working Group (stat. nov.), Duparquetioideae Legume Phylogeny Working Group (stat. nov.), and Papilionoideae DC. The traditionally recognised subfamily Mimosoideae is a distinct clade nested within the recircumscribed Caesalpinioideae and is referred to informally as the mimosoid clade pending a forthcoming formal tribal and/or cladebased classification of the new Caesalpinioideae. We provide a key for subfamily identification, descriptions with diagnostic charactertistics for the subfamilies, figures illustrating their floral and fruit diversity, and lists of genera by subfamily. This new classification of Leguminosae represents a consensus view of the international legume systematics community; it invokes both compromise and practicality of use.

effects of logging and recruitment on community phylogenetic structure in 32 permanent forest plots of kampong thom, cambodia

Ecological communities including tropical rainforest are rapidly changing under various disturbances caused by increasing human activities. Recently in Cambodia, illegal logging and clear-felling for agriculture have been increasing. Here, we study the effects of logging, mortality and recruitment of plot trees on phylogenetic community structure in 32 plots in Kampong Thom, Cambodia. Each plot was 0.25 ha; 28 plots were established in primary evergreen forests and four were established in secondary dry deciduous forests. Measurements were made in 1998, 2000, 2004 and 2010, and logging, recruitment and mortality of each tree were recorded. We estimated phylogeny using rbcL and matK gene sequences and quantified phylogenetic α and β diversity. Within communities, logging decreased phylogenetic diversity, and increased overall phylogenetic clustering and terminal phylogenetic evenness. Between communities, logging increased phylogenetic similarity between evergreen and deciduous plots. On the other hand, recruitment had opposite effects both within and between communities. The observed patterns can be explained by environmental homogenization under logging. Logging is biased to particular species and larger diameter at breast height, and forest patrol has been effective in decreasing logging.

Comparative phylogeography of two closely related Viola species occurring in contrasting habitats in the Japanese archipelago

Similar distribution ranges shared by closely related plant species may have been shaped through different migration histories if those species have differing habitat preference. To test this hypothesis, phylogeographical patterns and population genetic structures were compared between two sister Viola species: Viola eizanensis preferring woodland and V. chaerophylloides var. sieboldiana preferring grassland, both being native to the Japanese Archipelago. Amplified fragment length polymorphism (AFLP) was used for phylogenetic reconstruction, together with Bayesian ancestry analysis, AMOVA, analysis of genetic diversity statistics, and analysis of the relative contribution of each population to total diversity. The results indicated that V. eizanensis had two distinct lineages occurring in the western and eastern part of Japan, but such lineages are not distinct in V. chaerophylloides var. sieboldiana. Both species exhibited the low genetic diversity and high between-population differentiation typical of selfing plants. In V. chaerophylloides var. sieboldiana, one particular population made a significantly higher contribution to the total heterozygosity (HT), whereas in V. eizanensis, no population was identified as making a particularly higher contribution to HT. These findings suggest that V. eizanensis had been isolated in two large glacial refugia, whereas populations of V. chaerophylloides var. sieboldiana were restricted to a single small refuge. Different light requirements between these two closely related species probably caused these differing responses to climatic change during the last ice age.

Strategies to Observe and Assess Changes of Terrestrial Biodiversity in the Asia-Pacific Regions

Biodiversity loss is one of the most critical threats to global environments that has already transgressed planetary boundaries (Rockstrom et al. 2009). Indeed, nonlinear, often abrupt changes can drive unacceptable and irreversible deterioration. Rockstrom et al. (2009) claimed that earth’s system cannot sustain the current rate of biodiversity loss without significant erosion of resilience. To halt this biodiversity loss, global efforts to achieve “by 2010 a significant reduction of the current rate of biodiversity loss at the global, regional, and national level,” called the 2010 biodiversity targets, have been made since the agreement by the world’s governments in 2002. However, the latest data on the status and trends of biodiversity summarized in the third edition of Global Biodiversity Outlook (GBO-3) show that the target had not been met (Secretariat of the Convention on Biological Diversity 2010).

Goniothalamus flagellistylus Tagane & V. S. Dang (Annonaceae), a new species from Mt. Hon Ba, Vietnam

Abstract A new species, Goniothalamus flagellistylus Tagane & V. S. Dang, sp. nov. from Hon Ba Nature Reserve in Khanh Hoa Province, South Vietnam is described and illustrated. This species is most similar to Goniothalamus tortilipetalus M.R.Hend., but distinct in having 308–336 stamens (vs. ca. 170–260) and ca.120 carpels (vs. ca. 50–100) per flower, and Stigma and pseudostyles ca.8.5 mm (vs. 4–4.5 mm) long.

Homalium glandulosum (Salicaceae), a new species from Vu Quang National Park, North Central Vietnam

Abstract Homalium glandulosum Tagane & V. H. Nguyen, from Vu Quang National Park in northern Vietnam, is newly described. This species is characterized by distinct glands, often stalked, at the base of the lamina and along the margin of the stipules and bracteoles. Illustrations, DNA barcodes of the two regions of rbcL and matK, and a key to the species of Homalium in Vietnam are also provided.

Aporosa tetragona Tagane & V. S. Dang (Phyllanthaceae), a new species from Mt. Hon Ba, Vietnam

Abstract A new species, Aporosa tetragona Tagane & V. S. Dang, sp. nov., is described and illustrated from Mt. Hon Ba located in the Khanh Hoa Province, South Vietnam. This species is characterized by tetragonal pistillate flowers and fruits, which are clearly distinguishable from the other previously known species of the genus. The morphology and phylogeny based on rbcL and matK of this species indicated that the new species belongs to section Appendiculatae Pax & K. Hoffm.

Garcinia hopii (Clusiaceae), a new species from Bidoup Nui Ba National Park, southern Vietnam

Abstract A new species, Garcinia hopii H.Toyama & V.S.Dang is described from Bidoup Nui Ba National Park, southern Vietnam. This species is similar to Garcinia hendersoniana Whitmore but differs from that species in having larger leaves, clustered pistillate flowers, a greater number of sterile anthers and a larger stigma of young fruits. A description, preliminary conservation assessment, illustration, photographs and DNA barcodes of the new species are provided, as well as an updated key to Garcinia sect. Hebradendron in Indochina.

A new species of Eustigma (Hamamelidaceae) from Hon Ba Nature Reserve, Vietnam

Abstract A new species of Hamamelidaceae, Eustigma honbaense H.Toyama, Tagane & V.S.Dang, sp. nov., is described from Hon Ba Nature Reserve, Vietnam. This species is similar to Eustigma oblongifolium Gardner & Champ., but differs from it in having entire leaves, longer infructescences, capsules with a longer apical part and seeds with a larger hilum. A description, preliminary conservation assessment, illustration and photographs of the new species are provided, as well as an updated key to the genus Eustigma.

Lasianthus honbaensis (Rubiaceae), a New Species from Southern Vietnam

Lasianthus honbaensis V.S. Dang, Tagane & H. Toyama sp. nova (Rubiaceae) is described and illustrated from Hon Ba Nature Reserve, Khanh Hoa Province, southern Vietnam. It resembles L. inodorus and L. inodorus subsp. pubescens in leaf morphology, but differs from them in having shorter stipules, calyx tubes and corolla, and orange fruits. It is also similar to L. latifolius and L. calycinus in deeply disected calyx lobes and orange fruits, but differs from them by having persistent bracts and shorter calyx tubes. A table comparing the new species with its closest allies is provided.