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— Lithocarpus cadamensis Ngoc & Son, a new species of Fagaceae, is described and illustrated from Mt. Ca Dam, Tra Bong District, Quang Ngai Province, central Vietnam. The new species is characterized by its large leaf blades with long petioles, solitary and subsessile cupules which almost completely cover the nut, and spiny cupule scales, in a combination that clearly differs from the previously known species of Lithocarpus including the most similar species in the region, L. campylolepis, L. eucalyptifolius, and L. gougerotae. A MIG-seq phylogeny based on genome-wide SNPs reveals a phylogenetic position close to L. eucalyptifolius, from which the new species is differentiated by multiple morphological characters. A morphological description and comparison with related species, photographs, line drawing, preliminary conservation status, and DNA barcode sequences are provided for the new species.

An unknown species of the genus Sedum was discovered in Kawara-dake and Ryu-ga-hana, limestone mountains in Kyushu, Japan. The present study aimed to clarify the taxonomic status of the unknown Sedum species through morphological and ecological comparisons and molecular phylogenetic analysis using ITS sequences based on comprehensive taxon sampling of sect. Sedum in East Asia. Morphologically and ecologically, the unknown species was most similar to S. lipingense in China, but was distinguished by having larger spatulate rosulate leaves and more flowers per flowering stem. Phylogenetically, it belonged to a clade with four Chinese endemics including S. lipingense and two other species widely distributed in East Asia. The clade showed polytomy at the base, but the unknown species was genetically differentiated from the other species. Therefore, we describe the unknown species from Kawara-dake as a new species, S. kawaraense.

Three new species, Lithocarpus bidoupensis Ngoc & Tagane, L. congtroiensis Ngoc & Yahara, and L. hongiaoensis Ngoc & Binh are described from Bidoup-Nui Ba National Park, Central Highland of Vietnam. Morphological analyses and Maximum likelihood tree based on genome-wide SNPs support the distinction of those species from the previously known taxa in the region. The three new species are considered to be endemic to the Bidoup-Nui Ba National Park and the preliminary conservation status for each species is evaluated as Critically Endangered.

Hydrangea marunoi Tagane & S. Fujii, from the Kimotsuki Mountains in the Ohsumi Peninsula, southern Japan, is described and illustrated. It is morphologically similar to H. alternifolia in having three-petaloid calyx lobes in marginal flowers, but is distinguished by the larger stamen number, and longer styles and seeds. Multiplex ISSR genotyping by sequencing (MIG-seq) demonstrated that the new species is monophyletic and closely related to H. amamiohsimensis and H. moellendorffii rather than H. alternifolia.

A new species, Quercus sontraensis Ngoc, Binh & Son is described from Son Tra Nature Reserve, Son Tra Peninsula, Central Vietnam. We examined the morphology and constructed a highly resolved phylogeny of Q. sontraensis and its relatives (including Q. langbianensis and Q. cambodiensis) using Multiplex ISSR genotyping by sequencing (MIG-seq). The morphological analyses and molecular evidence support the distinction between the new species (Q. sontraensis) and its relatives.

Six pteridophyte species of five families and 12 spermatophyte species of 10 families are reported from Bolaven Plateau, southern Laos, as new records to the flora of Laos. Moreover, two new species, Sterculia bolavenensis (Malvaceae) and Wikstroemia bolavenensis (Thymelaeaceae), are described. For each species, voucher specimens are cited, photographs are shown and additional information including geographical distribution, ecology and taxonomic notes are provided.

A new species of Paraboea (Gesneriaceae), P. khotamiae, from a limestone karst in central Laos, is described and illustrated. The species resembles Paraboea bintangensis, P. prazeri and P. robusta, but differs in leaf shape and floral features, especially corolla shape and size, the interior of the corolla tube, and capsule characters. In addition, we report the occurrence of Middletonia reticulata (Gesneriaceae) for the flora of Laos for the first time.

A new species of Diospyros, D. laoensis, from Nam Kading National Protected Area, central Laos, is described and illustrated. It morphologically resembles D. longipilosa of Thailand, D. martabanica of India and Southeast Asia, and D. xishuangbannaensis of China, but is distinguished by its adaxially glabrous midrib, shorter calyx lobes and shorter fruiting pedicel. DNA barcodes of the rbcL and matK regions, a vernacular name and preliminary conservation assessment are also provided. As the species is considered to be endemic to a restricted area which is under threat from deforestation, it is here suggested for assessment under the category of Endangered (EN) within the IUCN Red List of Threatened Species.

Yooprasert, Sawita, Culham, Alastair, Tagane, Shuichiro, Yahara, Tetsukazu, Nguyen, Van Du, Nguyen, Khang Sinh, Utteridge, Timothy M. A. (2022): New species and new status of Urophyllum Wall. (Rubiaceae) from Cambodia and Viêtnam. Adansonia (3) 44 (11): 91-114, DOI: 10.5252/adansonia2022v44a11

This paper presents a re-evaluation of the taxonomic identity of Sciaphila major described from Sarawak, Borneo, Malaysia which has been considered conspecific with S. secundiflora. We revealed that S. major is clearly distinguishable from S. secundiflora s.s. by the arrangement of flowers on rachis (spirally and subdensely arranged vs. secundly and laxly arranged), rachis length in a fully developed inflorescence [(2–)3–6(–7) cm vs. 6–19 cm], tepal length of male flowers (2–2.3 mm vs. 3–4 mm) and the number of perianth segments (more than 6 vs. 6). By spirally-arranged and white flowers, S. major is most similar to S. alba, but is distinguishable by plant height (15–25 cm vs. 25–35 cm in S. alba), rachis length in a fully developed inflorescence [(2–)3–6(–7) cm vs. 8–14 cm)], the number of flowers (usually less than 20 vs. usually more than 20), the arrangement of flowers on rachis (subdensely arranged vs. laxly arranged), the number of male perianth segments (usually more than 6 vs. usually 6) and the condition of floral disc (flat vs. bowl-shaped). We also provide an updated key to the species of Sciaphila distributed in Borneo.

Mallotus tokiae (Euphorbiaceae), a poorly known species, was described based upon a single fruiting specimen from Surat Thani Province, peninsular Thailand. We found this species with staminate and slightly mature pistillate flowers in Lampi Island, Myanmar. A new locality record, description of flowers, preliminary conservation assessment and DNA barcoding of this species are provided.

An unknown taxon of Stellaria was discovered in Yakushima, a Japanese island known to harbor several endemic species. To determine the identity of this taxon, this study employed MIG-seq for the reconstruction of a finely resolved phylogenetic tree of the newly discovered taxon, along with some related species of Stellaria. The results showed that the newly discovered taxon is a relative of S. alsine. Based on this result, Stellaria alsine subsp. nanasubsp. nov. was published.

Molecular phylogenetic studies of Hosta pulchella (Asparagaceae) and its relatives, which are native to Japan, have been conducted and resulted in a highly resolved phylogeny. Specifically, the relationship of H. pulchella to H. alata Hatusima, nom. nud. is investigated. These data include genome-wide SNPs obtained through conducting multiplexed ISSR genotyping by sequencing (MIG-seq). Based on these phylogenetic results, morphological observations, distribution, and differences in flowering periods of H. alata collections sympatric with H. pulchella, we find the two species closely related, but distinct. As such, we formally describe Hosta alatasp. nov. from the Oita Prefecture of Kyushu island, southwestern Japan.

Premise Flowering phenology may differ among life forms due to the costs and benefits to attract pollinators, dependence on outcross pollination, and resource availability in their habitats. However, few studies have compared flowering phenology among life forms within a community and described flowering phenology at the individual, species, and community levels. Methods We recorded flowering events for individuals of insect-pollinated trees, perennial herbs, and annuals from spring to summer of 2016 and 2017 in a warm-temperate forest in Japan. To compare phenological variables including mean and variance of flowering length, we standardized the number of observed individuals for each species and tested differences in variables, considering the phylogenetic relationships among species. Results Total flowering length in trees (9-50 d) was significantly shorter than perennial herbs (27-113 d) or annuals (22-89 d), but mean flowering length was not significantly different among them. Flowering length variance was significantly smaller and intraspecies synchrony significantly higher in trees than in perennial herbs and annuals. At the community level, flowering times largely overlapped among successively flowering species, but interspecies synchrony was positive for all life forms. Conclusions Shorter total flowering length and higher intraspecific synchrony in trees are explained by a modified pollinator attraction hypothesis suggesting that selection favors higher intraspecific synchrony because it promotes between-individual movement of pollinators. At the community level, positive interspecific synchrony for all life forms supports the hypothesis that flowering times tend to converge among species.

A new species, Gynochthodes honbaensis (Rubiaceae), from Hon Ba Nature Researve, Khanh Hoa Province, southern Vietnam, is described, with a key to the species of Gynochthodes in Vietnam. This species is phenotypically most similar to G. macrophylla distributed in Nicobar Islands, Thailand, and Peninsular Malaysia, but differs in having smaller leaves, and much longer and glabrous peduncles.

A new species of Lauraceae,Cryptocarya kaengkrachanensisM.Z.Zhang, Yahara & Tagane, from Kaeng Krachan National Park, Phetchaburi Province, southwestern Thailand, is described and illustrated. This species is morphologically most similar toC. amygdalinain that its leaves are pinnately veined, leathery, and apparently glabrous (but microscopically hairy) abaxially, twigs are yellowish brown hairy, and fruits are 1.36 to 1.85 times longer than width. However,C. kaengkrachanensisis distinguished fromC. amygdalinain having the leaves of ovate and elliptic (vs. oblong-lanceolate) with leaf aspect ratio (length:width) from 1.38 to 2.28 (vs. 2.46–3.43), and ovoid fruits (vs. ellipsoid) with stalk distinctly swollen (vs. not or only slightly swollen). In addition, phylogenetic trees constructed based on internal transcribed spacer sequences (ITS) and genome-wide SNPs using MIG-seq showed thatC. kaengkrachanensisis not sister toC. amygdalinaand is distinct from all the otherCryptocaryaspecies hitherto recognized in Thailand. Analysis including other species demonstrates thatC. floribundashould be a synonym ofC. amygdalina, but we recognizeC. scortechiniias a distinct species.

Didymocarpus middletonii Souvann., Soulad. & Tagane, a new species of Gesneriaceae from Nam Kading National Protected Area, is described and illustrated. The new species is morphologically similar to Didymocarpus brevicalyx, D. formosus and D. puhoatensis but distinguished from the three by its fewer-flowered inflorescence, longer pedicel, and urceolate and multicellular eglandular hairy calyx. Based on the latest IUCN criteria, Didymocarpus middletonii is proposed to be Critically Endangered (CR). Our record of Didymocarpus represents a new genus record for the flora of Laos.

Cardamine occulta, recently reported also as 'Asian C. flexuosa', is originally a native East Asian weed of paddy fields and other open habitats. It has been recorded throughout the world and is now also spreading widely in Europe. However, how this species differs morphologically from European C. flexuosa and its closest relatives in Asia (C. kokaiensis and C. scutata) is not fully known, particularly because it became widely recognized as a new taxon only recently. We used chromosome counting and flow cytometry to determine ploidies and genome size variation in these four species and morphometric analyses to ascertain their morphological differentiation. A uniformly octoploid level (2n = 64) is confirmed here for C. occulta and a tetraploid level for C. flexuosa and C. scutata (2n = 32). Here we formally describe C. kokaiensis, which is restricted to East Asia (Japan, Honshu; eastern China, Zhejiang Province; perhaps also the Russian Far East) and determine it to be a tetraploid. Considerable differences in monoploid genome size were revealed between these taxa, suggesting their mostly allopolyploid origins. Morphological differences between the species are demonstrated, and detailed morphological descriptions and an identification key are provided.

In wind-pollinated plants, apical damage may decrease male fitness by reducing height-dependent pollen dispersal distance, but may not affect female fitness because plant height is not always correlated with female fitness. We hypothesized that Ambrosia artemisiifolia responds to apical damage by (1) restoring plant height through compensatory growth from lateral buds, and/or (2) increasing the sex allocation to female function to compensate for the loss of male fitness. We tested these hypotheses by comparing a group of experimental removal of the apical meristem with three control groups and by field surveys on apically damaged plants. Experimental apical damage suppressed main stem growth, but promoted vertical secondary growth from lateral buds. These responses resulted in compensation of stem height in the apically damaged plants to the same height as one of three control groups. The numbers of male and female flowers and male racemes did not differ between damaged and undamaged plants, indicating that apically damaged plants did not change their sex allocation. Therefore, our results support our first hypothesis. The results of a field survey of naturalized populations also supported the first hypothesis in that plant height and the number of male racemes did not change in plants with apical damage. Consequently, our results suggest that A. artemisiifolia has a high ability of fitness compensation after apical damage by restoring height and male function. This ability may contribute to its invasiveness in disturbed habitats.

Some plants rapidly close their leaves in response to mechanical stimulation, but no case is known in which mechanical stimulation causes rapid petal closure. In this study, we found that Drosera tokaiensis closes petals within 2–10 min after experimental stimulation of the calyx, closed flowers or scapes with a pair of tweezers. Although petal closure was induced more rapidly by touching a position closer to a flower, it was not induced by stimulating stamens and pistils. The habit of petal closure varies among species of Drosera: after experimental stimulations of the calyx or scapes, D. tokaiensis and D. spatulata often closed petals but D. rotundifolia and D. toyoakensis did not close them. The petal closure may function as defense against a specialist florivore.

A new species, Quercus xuanlienensis Binh, Ngoc & Bon, is described from Xuan Lien Nature Reserve, Vietnam. The new species is morphologically similar to Q. edithiae Skan, in having 8–11 pairs of secondary veins, bowl-shaped cupules and ellipsoid to cylindrical-ellipsoid and basally convex nuts. It differs in having serrulate leaf margins only at apical 1/5–1/7, almost entire margins of bracts on cupule and much longer nuts. The species is also similar to Q. fleuryi Hickel & A. Camus in having leaves glabrous on both surfaces with only an apically serrulate margin but differs in having shorter petioles, cupules enclosing 1/5 of the nut and much longer nuts. In addition, Q. disciformis Chun & Tsiang. and Q. bella Chun & Tsiang., previously known from China, are newly recorded from Ba Vi National Park, Vietnam.

A new species of Gentiana (Gentianaceae), G. laotica Soulad., Tagane & Yahara, from Phou Khao Khouay National Protected Area, Vientiane Province, central Laos, is described. Photographs, vernacular name, DNA barcodes of rbcL, matK and ITS, and preliminary conservation status are provided for the new species.

Thirty angiosperm species in 20 families, collected in Nam Kading National Protected Area, are recorded in Laos for the first time. Because the flora of Nam Kading is rich in endemic species, the area represents one of the core sites of plant biodiversity in Laos. To elucidate the plant diversity accurately, further intensive floristic surveys are required.

A new species of Acanthaceae, Strobilanthes namkadingensis Soulad. & Tagane from Nam Kading National Protected Area, Bolikhamxay Province, central Laos, is described and illustrated. It is characterized by long spicate inflorescences consisting of 6-32 flowers, yellow corolla, the absence of long white hairs on the bracts and 4–6 seeds per capsule. Three DNA barcode regions of the partial genes for the large sub-unit ribulose-1,5-bisphosphate carboxylase oxygenase (rbcL) and maturase K (matK) and internal transcribed spacers (ITS) are also provided.

Macrosolen bidoupensis Tagane & V.S.Dang, sp. nov. (Loranthaceae) is newly described from Bidoup Nui Ba National Park in Lam Dong Province, southern Vietnam. The new species is characterized by small broadly elliptic to circular leaves, sessile to short petioles, slightly cordate to rounded leaf bases, 4–5 pairs of lateral veins and a basally green corolla tube. An illustration, a summary of DNA barcoding of the plastid genes rbcL and matK, and a key to the species of Macrosolen in Vietnam are provided.

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 recircum-scribed Caesalpinioideae and is referred to informally as the mimosoid clade pending a forthcoming formal tribal and/or clade-based 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.

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 Asplenium (Aspleniaceae), A. minutifolium Kanem. & Tagane, from Phu Kradueng National Park, Loei Province, Northeast Thailand and Khao Yai National Park, Nakhon Nayok Province, Central Thailand, is described and illustrated. This species can be distinguished from all similar species in East and South-East Asia by its simple and small lamina (1–5 × 0.3–0.7 cm), small and entire pinnae (1–4 × 0.8–2.5 mm), reflexed pinna arrangement (>90° from the midrib) in the lower 2/3 of the lamina and a sori arrangement that is almost always arranged in a single row on the basiscopic vein.

Lithocarpus dahuoaiensis Ngoc & L. V. Dung, a new species from the Central highland of Vietnam, is described and illustrated. The new species is morphologically similar to Lithocarpus macphailii (M. R. Hend.) Barnett or Lithocarpus encleisocarpus (Korth.) A. Camus in having completely entire leaf margin, solitary cupule, long stalks of fruits, deeply cup-shaped or turbinate cupules, with a number of horizontal filiform lines. The species differs in its nut enclosure ca. 1/2 – 2/3 of the nut, adaxially glabrous leaf blades, secondary veins 11–12 pairs and faintly to very faintly visible hairs on the outside of the cupule. A table showing the morphological comparison of Lithocarpus dahuoaiensis with Lithocarpus macphailii and Lithocarpus encleisocarpus is also provided.

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.

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.

Two new species, Machilus bokorensis Yahara & Tagane and Machilus brevipaniculata Yahara & Tagane (Lauraceae) are described from Bokor National Park, Cambodia with their illustrations and DNA barcodes of the two plastid regions of rbcL and matK and the nuclear region of ITS.

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.

A new species, Glycosmis suberosa H.Toyama & Rueangr. is described from Khao Luang National Park, Nakhon Si Thammarat Province, Thailand. This species is distinguished from the other Glycosmis species by its characteristic corky branches.

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.

Lithocarpus vuquangensis Ngoc & Hung is described from Vu Quang National Park, North Central Vietnam. The morphological comparison and phylogenetic analysis based on rbcL, matK and ITS provided evidence that the new species was not assignable to any of the previously known taxa in Vietnam and its surrounding countries. The description, photographs, preliminary conservation status and DNA barcode sequences are also provided for the new species.

The taxonomy of Quercus langbianensis and its relatives in Vietnam and Cambodia have been revised based on evidence obtained from field observations, morphological comparison of herbarium specimens and molecular analyses using both classic and next generation DNA markers. Based on Bayesian inference using rbcL, matK and ITS regions and Neighbour-joining tree using genome-wide sequences amplified with multiplexed inter-simple sequence repeat (ISSR) primers (MIG-seq), the authors recognised ten species in the complex in Vietnam and Cambodia, three of which are newly described in this paper: Q. baolamensis sp. nov., Q. bidoupensis sp. nov. and Q. honbaensis sp. nov. These new species are all phenotypically similar to Q. langbianensis s. str. in having lanceolate to oblanceolate leaf shape, upper 4–5/6–serrated leaf margin, acute or acuminate leaf apex and bracts of cupule arranged in 5–9 rings but distinguished both morphologically and phylogenetically. In molecular phylogenetic reconstructions, Q. bidoupensis is not close to any other species. In the Bayesian tree, Q. honbaensis is sister to both Q. blaoensis and Q. camusiae that are found in the same locality but morphologically distinct and those three species are sister to Q. langbianensis s. str., while Quercus baolamensis is not sister to Q. langbianensis s. str. in both the Bayesian tree and MIG-seq tree. In addition, Q. cambodiensis and Q. baniensis previously reduced to Q. langbianensis s. lat. have been recognised as distinct species. Six species were in need of lectotypification and that is undertaken herein.

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.

The genus Stevia comprises approximately 200 species, which are distributed in North and South America, and are representative of the species diversity of the Asteraceae in the New World. We reconstructed the phylogenetic relationships using sequences of ITS and cpDNA and estimated the divergence times of the major clade of this genus. Our results suggested that Stevia originated in Mexico 7.0–7.3 million years ago (Mya). Two large clades, one with shrub species and another with herb species, were separated at about 6.6 Mya. The phylogenetic reconstruction suggested that an ancestor of Stevia was a small shrub in temperate pine–oak forests and the evolutionary change from a shrub state to a herb state occurred only once. A Brazilian clade was nested in a Mexican herb clade, and its origin was estimated to be 5.2 Mya, suggesting that the migration from North America to South America occurred after the formation of the Isthmus of Panama. The species diversity in Mexico appears to reflect the habitat diversity within the temperate pine–oak forest zone. The presence of many conspecific diploid–polyploid clades in the phylogenetic tree reflects the high frequency of polyploidization among the perennial Stevia species.

Hybrid zones formed from genetically and ecologically differentiated species provide an opportunity to examine how genetics and ecology interact to determine species boundaries. In this study, we examined a hybrid zone generated by invasion of shade-loving Viola eizanensis into habitat occupied by its close relative, V. chaerophylloides var. sieboldiana, which prefers more open areas. We used 339 AFLP loci to estimate genomic composition and generation of hybrids, and confirmed maternal inheritance through sequencing of the cpDNA atpI–atpH intergenic spacer region. Phenotypic variation was assessed using leaf thickness (leaf mass/area) and leaf dissection (leaf perimeter/area), which were diversified between species. Genetic analyses showed that the AFLP of hybrid individuals in having maternal origin from V. chaerophylloides var. sieboldiana were replaced by V. eizanensis in response to habitat. Significant correlations were observed between hybrid indices and the two leaf traits. These results suggest that genes of V. eizanensis that are adaptive to shaded habitats are fixed in the hybrids, and that the degree of leaf thickness and dissection is important in adaptation of the hybrids to their light environments.

Summary 1. Taller plant species can pre-empt solar energy and suppress growth of subordinate species in vegetation stands, which is described through one-sided competition. Yet, in much of the world’s vegetation species of different statures coexist. This study aims to clarify the mechanisms underlying this apparent paradox. 2. We quantified how co-occurring species and individuals intercepted and used light for growth in a mature, warm-temperate evergreen forest. This was performed by determining the 3D distribution of foliage and light with a ground-based lidar system in combination with nondestructive measurements of plant growth. 3. Taller trees intercepted light more efficiently per unit of above-ground biomass than shorter trees did (=higher light interception efficiency, LIE). However, taller trees tended to have lower biomass production per unit light interception (=lower light use efficiency, LUE). Reduced LUE in taller trees was associated with their higher biomass allocation to nonphotosynthetic organs and probably with over-saturated light intensity for photosynthesis at high canopy positions. Due to the increased LIE and decreased LUE with tree heights, a trade-off between LIE and LUE was found, and this trade-off resulted in trees of different statures having similar relative growth rates. 4. Synthesis. Light competition drives trees to grow taller, and the light interception efficiency is higher in taller trees; however, this benefit comes at a cost of decreased efficiency of light use for growth. This trade-off allows trees of different statures to grow at proportionally comparable rates and may promote coexistence of tree species in one-sided light competition.

The genus Dalbergia with c. 250 species has a pantropical distribution. In spite of the high economic and ecological value of the genus, it has not yet been the focus of a species level phylogenetic study. We utilized ITS nuclear sequence data and included 64 Dalbergia species representative of its entire geographic range to provide a first phylogenetic framework of the genus to evaluate previous infrageneric classifications based on morphological data. The phylogenetic analyses performed suggest that Dalbergia is monophyletic and that it probably originated in the New World. Several clades corresponding to sections of these previous classifications are revealed. Taking into account that there is not a complete correlation between geography and phylogeny, and the estimation that the Dalbergia stem and crown clades are 40.4–43.3 mya and 3.8–12.7 mya, respectively, it is plausible that several long distance dispersal events underlie the pantropical distribution of the genus.

Agamospermous dandelions of hybrid origin between a native sexual diploid species (Taraxacum platycarpum Dahlst. or T. japonicum Koidz.) and an alien agamospermous triploid [T. officinale Weber and T. laevigatum (Willd.) DC.] are now widely distributed throughout mainland Japan. These hybrid dandelions are known to be genetically variable. We hypothesized that this variability is maintained by repeated ongoing hybridization, based on the fact that triploid dandelions not only produce seeds agamospermously, but also produce some functional pollen grains that are able to sire seeds of sexual dandelions. To test this hypothesis, we examined whether heads of Japanese diploid dandelions produce new hybrid seeds after fertilization by pollen from triploid agamosperms under field conditions. One of the 430 tested plants grown from sexual dandelion seeds had morphological and molecular characteristics, which are consistent with a hybrid origin. The plant formed a hybrid surrounded by many individuals having recurved involucral bracts, in which frequency of T. officinale was very low (3.5 %). Cytological data and bagging experiments demonstrate triploidy and asexual seed production of the hybrid. Taken together, these results supported that the new hybrid is probably derived from a backcross of a hybrid to the native sexual species. Our findings provide evidence for the evolution of a new agamosperm through interspecific hybridization as a contemporary population process.

While many plant species are considered threatened under anthropogenic pressure, it remains uncertain how rapidly we are losing plant species diversity. To fill this gap, we propose a Global Legume Diversity Assessment (GLDA) as the first step of a global plant diversity assessment. Here we describe the concept of GLDA and its feasibility by reviewing relevant approaches and data availability. We conclude that Fabaceae is a good proxy for overall angiosperm diversity in many habitats and that much relevant data for GLDA are available. As indicators of states, we propose comparison of species richness with phylogenetic and functional diversity to obtain an integrated picture of diversity. As indicators of trends, species loss rate and extinction risks should be assessed. Specimen records and plot data provide key resources for assessing legume diversity at a global scale, and distribution modeling based on these records provide key methods for assessing states and trends of legume diversity. GLDA has started in Asia, and we call for a truly global legume diversity assessment by wider geographic collabora- tions among various scientists.

A new species, Callicarpa bachmaensis Soejima & Tagane, sp. nov., is described and illustrated from Bach Ma National Park in Thua Thien Hue Province, Central Vietnam. This species has a characteristic liana habit, white corolla, and narrowly elliptic to narrowly lanceolate, entire, occasionally subequal leaves, by which it is clearly distinguished from the other previously known species of this genus.

A new species, Popowia bachmaensis Ngoc, Tagane & Yahara, sp. nov. is described from Bach Ma National Park in Thua Thien Hue Province, Central Vietnam. This species is morphologically similar to Popowia pisocarpa (Blume) Endl. ex Walp., but can be readily distinguished from it by its lower stems, smaller leaves, shorter flowering pedicels, shorter carpels, longer sepals and inner petals. A detailed description, comprising illustrations, and supplemented with DNA barcodes of the two regions of rbcL and matK, are provided.

Floral traits such as color and size are highly diversified in lilies, but their adaptive significance remains uncertain. In the present study, we compared pollination processes between Lilium japonicum var. abeanum and var. japonicum to clarify how the two varieties are adapted to different pollinators. Lilium japonicum var. japonicum is known to be pollinated by moths, and we hypothesized from its flower traits that var. abeanum is pollinated by diurnal insects. Using waterproof digital cameras set to a recording interval of 10–30 s, we recorded flower visitors for 7–9 flowers of var. japonicum and 4–6 flowers of var. abeanum over 24-h periods. We also recorded the number of versatile (T-shaped) and rigid (I-shaped) anthers per flower. For var. abeanum, we observed flowers at 05.00 and 17.00 hours to determine flower opening time and measured the intensity of floral scent using a metal-oxide semi-conductor odor sensor. Both diurnal and nocturnal insects visited flowers of the two varieties, but visitation of diurnal insects was more frequent in var. abeanum. Anthers of var. abeanum are usually rigid, as in many bee-pollinated flowers, whereas those of var. japonicum are mostly versatile. Although flowers of var. japonicum are known to open in the evening, 32% of the flowers of var. abeanum started to flower during the day. Lilium japonicum var. abeanum emitted scent at night, with a maximum intensity at 20.00 hours, just as in var. japonicum. These findings suggest that the floral traits of the two varieties are adapted to the different relative availabilities of nocturnal versus diurnal pollinators. The flower of var. abeanum is more adapted to diurnal pollinators, but retains adaptations to nocturnal pollinators, particularly with regard to its scent.

Five new species of Syzygium (Myrtaceae), S. honbaense, S. phamhoangii and S. yersinii from Khanh Hoa Province, Vietnam, S. phoukhaokhouayense from Phou Khao Khouay National Protected Area, Vientiane Province, Laos, and S. scabrum from Bung Khla, Phu Wua Wildlife Sanctuary, Buengkan Province, Thailand, are described and illustrated. Photographs, vernacular names and preliminary conservation assessments are provided for them.

Erythroxylum calyptratum, sp. nov. (Erythroxylaceae), from Mt. Fansipan, Hoang Lien National Park, Lao Cai Province, northern Vietnam, is newly described. The new species is characterized by thinly chartaceous leaves with 2–3 mm long petiole, 1–3 flowered inflorescences, downward facing white flowers, well-developed petal appendages (1/3–1/2 length of petals) and entirely free 3 styles. A description, illustrations, DNA barcodes of rbcL and matK and a key to the species of Erythroxylum in Indochina are provided.