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This paper presents a biomechanical study of stems of two liana species, Clematis vitalba and Vitis vinifera, investigates the mechanical performance of these two liana species and attempts to enhance the understanding of structure–function relationships. The investigation involved mechanical testing of whole plant stems, supplemented by X-ray micro-CT (X-ray computed tomography at micron voxel size) imaging and 2D microscopic images of stained cross sections of the plant stems, to derive structure–function relationships with potential for application in bioinspired composite materials. The micro-CT images were compared to the microscopic images of stained cross sections, in order to show benefits and potential drawbacks of the X-ray micro-CT method with respect to traditional methods. The high-resolution 3D imaging capacity of micro-CT is exploited to explain the structural functionality derived from the mechanical testing. A simple finite element model is developed based on the plant topology derived by the micro-CT images and proved accurate enough to model the plant’s mechanical behaviour and assess the influence of their structural differences. The two plants exhibit different to each other physical and mechanical properties (density, strength and stiffness) due to their common growth form. Anatomical cross-sectional observation and X-ray micro-CT provide complementary information. The first method allows the identification of the lignified parts, supposedly more resistant mechanically, of these structures, while the second one provides a full 3D model of the structure, admittedly less detailed but providing the spatial distribution of density contrasts supposed to be important in the mechanical properties of the plant. The proposed methodological approach opens new perspectives to better understand the mechanical behaviour of the complex structure of plants and to draw inspiration from it in structural engineering. [ABSTRACT FROM AUTHOR]

The poroid species of Auriculariales have been placed in Aporpium, Elmerina, Protodaedalea and Protomerulius and include resupinate, effused-reflexed or pileate basidiomata, 4-celled basidia and globose, ovoid to allantoid basidiospores. According to recent DNA-based phylogenetic studies, those genera have good support in Auriculariales, but many species without phylogenetic treatment remain in uncertain taxonomic position, especially from the Neotropics. In the present paper, specimens with poroid hymenophore and septate basidia were collected in Brazil and morphological and DNA analyses, based in ITS and LSU regions, evidenced three new species (Elmerina brasiliensis, E. santanaensis and Protomerulis pedratalhadensis) and three new combinations (E. minipora, E. strigosa and E. obtusispora). Descriptions and illustrations of the new species, the new combinations and a comparative table of species of the genera are provided. [ABSTRACT FROM AUTHOR]

The Balkan Peninsula is widely acknowledged as one of the centers of European biodiversity and a major glacial refugium for plant species. Its extensive geographic heterogeneity and diverse mosaic of habitats, coupled with relatively high environmental stability over long periods, have enabled the diversification of lineages and simultaneously fostered the long-term survival of diverse species. The increasing number of phylogeographically studied plant species in the region has substantially contributed to a better understanding of the relationships among closely related taxa and provides significant insights into intraspecific lineage differentiation. The present paper reviews the current knowledge on plant phylogeography in the Balkan Peninsula. By providing an updated overview of the most recent studies dealing with the diversity and evolution of Balkan plants, we explore the phylogeographic patterns and roles of refugia in structuring genetic diversity and highlight the crucial evolutionary processes that shaped the diversity of plants in the region. Molecular clock-based estimations highlight the importance of Pleistocene climatic fluctuations across taxonomic groups and lineage distribution patterns corroborate the persistence of multiple glacial refugia. Spatial congruence in phylogeographic splits is determined and discussed. An examination of phylogeographic connections with adjacent regions (i.e., the Alps, Apennine Peninsula, Asia Minor, Carpathians, and central Europe) uncovers several consistent patterns. Additionally, allopatric and ecological speciation, polyploidy, and hybridization are identified as crucial evolutionary mechanisms acting in the Balkan Peninsula and shaping species diversity. Furthermore, the existing research gaps are identified and future approaches with the potential to better understand the unique Balkan flora are highlighted. [ABSTRACT FROM AUTHOR]

In 2015, Brazil faced the worst environmental disaster in its history, when the collapse of an iron ore dam dumped millions of tons of tailings into the Doce River. In this paper, we describe two Hippeastrum species native to localities directly involved in the tragedy. The dam was located in the foothills of Serra do Caraça, a mountain range in the state of Minas Gerais, from where we describe the endemic H.carassense; H.velloziflorum was first found on an inselberg located on the banks of the Doce River, in the neighboring state of Espírito Santo. Comments on their distribution, ecology, and phenology are provided, as well as comparisons with the most similar taxa. The conservation status of the two new species is preliminarily assessed, and both are considered threatened with extinction. We also compared their leaf anatomy and micromorphology with related species of Amaryllidaceae. Based on nrDNA ITS, we infer the phylogenetic position of H.velloziflorum, a taxon with several unique morphological characters for Hippeastrum, as the first branch in subgenus Hippeastrum. The placement of H.velloziflorum in Hippeastrum is also supported by anatomical and cytological data. The somatic chromosome number was 2n = 22, and the karyotype formula was 2n = 8m + 12sm + 2st chromosome pairs. An identification key to the species of Hippeastrum occurring in the Doce and Jequitinhonha River basins is presented. [ABSTRACT FROM AUTHOR]

The grass Deschampsia cespitosa is a variable taxon out of which many varieties, subspecies and endemic species have been separated. In this paper, the variation in genome size (GS) and ploidy of this grass including several of its subspecies and two related species in Eurasia was investigated by flow cytometric (FCM) measurements. GS and ploidy data were also related to specific environments and reproduction mode. Ploidy levels found by FCM were confirmed by chromosome counts of diploid (2n = 28) and tetraploid (2n = 52) samples. Seminiferous (seed bearing) D. cespitosa was mainly diploid (GS between 3.754 and 5.438 pg/1C). GS variation in diploids showed a geographic pattern with a significant difference (H = 41,441, P < 0.001) between European (median = 4.377 pg) and Asian (median = 4.881 pg) accessions. Genome size (1C) in tetraploids ranged from 7.9426 to 9.0399 pg. Tetraploid seminiferous D. cespitosa was found mostly in disturbed habitats in western and southern Europe, while tetraploids in Asia were registered in wet Arctic habitats. Genome size (1C between 8.3278 and 8.8603 pg) of the pseudoviviparous plants (spikelets produce plantlets asexually) of wet habitats in central and northern Europe indicated tetraploidy. A putative triploid (GS 6.6817 pg) was detected in Iceland. Summing up, we found a high variation in GS on the geographic scale with significant regional differences in diploid D. cespitosa. Among the tetraploids, the asexually reproducing plants were bound to specific habitats, while the seminiferous plants showed a habitat preference similar to the diploids. [ABSTRACT FROM AUTHOR]

In this paper we review the fragmentary fossil pollen record of Hamamelidaceae which extends back to the middle Eocene until the Early Pleistocene in the Iberian Peninsula. Records of fossil palynomorphs related to Hamamelidaceae are very scarce in the European Cenozoic, in part due to difficulty in confident identification at a generic or even familial rank. The present review contributes to improving the accuracy of identification of Cenozoic Hamamelidaceae in standard palynological studies, which should help trace its poorly understood fossil and evolutionary history. The review of all published Iberian records indicates a considerable generic diversity. At least four genera can be confidently identified. The examination of new material from the Oligocene of north-west Spain has led to the formal description of three new fossil pollen genera that are related to extant genera currently restricted geographically to Asia: Disanthuspollenites, Embolantherapollenites and Parrotiapollenites. Based on SEM analysis, a new combination of the fossil species Tricolpopollenites indeterminatus, traditionally used to designate fossil pollen related to Hamamelidaceae in Europe, is proposed. Additionally, we discuss the occurrence of pollen forms that can be tentatively attributed to Corylopsis and Fothergilla. [ABSTRACT FROM AUTHOR]

We propose here a new genus to accommodate Tragia rubiginosa, previously considered endemic to Peru, based on morphological characters, including pollen. A multivariate analysis was performed to assess the dissimilarity of T. rubiginosa in relation to Tragia and the other genera of Tragiinae. In this paper, we present a detailed morphological description, a full pollen description of the new genus, its geographic and ecological distribution, an identification key for all genera of Tragiinae, and a comparative table of the sections of Tragia and the American genera of Tragiinae. [ABSTRACT FROM AUTHOR]

Portulaca minensis is a poorly known species of Portulacaceae, considered exclusive to the campo rupestre vegetation in Minas Gerais, Brazil. It shares morphological features with members of the Cryptopetala clade, composed of P. mucronata, P. cryptopetala, and P. hirsutissima. The purpose of this paper is to expand the knowledge about the taxonomy, distribution, and micromorphology of P. minensis, comparing it to its morphologically related species occurring in the Espinhaço Range, along Eastern Brazil. We analyzed specimens of this group in herbaria and in the field and gathered data on micromorphology of seeds surface and pollen grains using scanning electron microscopy. In addition, we also analyzed leaf anatomy using light microscopy for the first time to this species. Portulaca minensis can be distinguished from its allies within the P. hirsutissima complex by glabrous leaves and sepaloid (vs. pilose) and from P. mucronata, it differs by reddish sepaloid structures (vs. greenish). As this species showed leaf anatomy with intermediate metabolism C3–C4, we consider it as a probable member of the Cryptopetala clade. The pantocolpate pollen grains were similar to most Portulaca species (except the P. hirsutissima complex), but the slightly convex ornate seeds with par-dome type projections were considered diagnostic to P. minensis. We also indicate new localities of occurrence to P. minensis in the state of Bahia, expanding the species distribution toward the Northeastern region. This species is classified as endangered according to the IUCN criteria (EN B1 + b(i, ii, iii), with EOO = 3,557,978 km2 and AOO = 28,000 km2. [ABSTRACT FROM AUTHOR]

Polystachya is a large, pantropical orchid genus of 200 species, most of which occur as epiphytes in sub-saharan Africa. The three-lobed labellum of most Polystachya species possesses a fleshy callus and various types of trichomes and papillae. In this paper, we present the results of micromorphological studies on the labellum of 20 species, representing eight of the 13 sections in the genus, using scanning electron microscopy (SEM). Our results show the scale of infrageneric diversity of trichomes and papillae relative to the sampled sections. They also demonstrate the taxonomic value of labellar micromorphology at the sectional level. The study revealed seven types of papillae and five types of trichomes (uni- and multi-cellular) in Polystachya, some of which, are described here for the first time. Clavate trichomes are the most common and are present in 60% of the species studied. Moniliform trichomes mainly occur in sect. Polystachya and are strongly characteristic of the section. Pseudopollen is formed by fragmentation of moniliform trichomes or the detachment of other trichomes as bicellular units. We provide, for the first time, evidence for the detachment of the terminal cells of capitate trichomes. [ABSTRACT FROM AUTHOR]

Odontarrhena is a taxonomically difficult genus of the tribe Alysseae, including a number of critical species complexes in the Balkan Peninsula. One of these is O. baldaccii, which was previously included in the inconsistent taxon Alyssum fallacinum but recently shown to be distinct from it. In this paper, we analyzed the still uncertain taxonomic circumscription of O. baldaccii by a comparative analysis of the population from the type locality in Crete and other populations from mainland Greece, which were previously attributed to A. fallacinum or dubitatively included in O. baldaccii s.l. The results supported the separation of these mainland populations in a new distinct species, here described as Odontarrhena stridii, sp. nov. Plant habit, leaf shape and size and silicle shape were the major distinguishing morphological characters. Molecular data also suggested divergence between the two groups of populations, while supporting their phylogenetic affinity. The two species are diploid schizo-endemics with 2n = 16, allopatric distribution and specialization for serpentine soils. Shoot Ni concentrations well above 1000 µg g−1 dry weight were confirmed for the Cretan population of O. baldaccii and found for the first time in two populations of O. stridii, which is therefore a new hyperaccumulating species of the Balkan Mediterranean flora. An updated key to the Greek Odontarrhena taxa is provided. [ABSTRACT FROM AUTHOR]

In this paper, we present a new online comprehensive database developed for genome-related information of Indian plants (dGRIP). In strict sense, dGRIP database displays for each species and genus, its chromosome number(s) with comprehensive cytogenetic data, genome size, ploidy, systematics and molecular genetics related to Indian angiosperms, gymnosperms, pteridophytes and bryophytes. The data are described in the form of datasheets encompassing 29 parameters available for users to consolidate the knowledge with respect to comprehensive cytogenetical details. The chromosome database is developed based on object-relational database management system (Sequence Query Language) and includes references from which the information was sourced. The online database is currently available at http://sbtju.in/Dgrip/index.html consists of a main page, project information, collaborators and search tools for each group, namely angiosperms, gymnosperms pteridophytes and bryophytes. Currently, the information is available for about 1500 species (Release 1.0); however, the dGRIP continues to expand with goal to include data of more than 17,000 plant species from India. [ABSTRACT FROM AUTHOR]

The taxonomy of the Cyanus tuberosus group has been unsettled since its first members were described in the nineteenth century. In this paper, we provide a revision of the group based on analyses of its genetic (amplified fragment length polymorphisms; 240 individuals), morphological (48 morphological traits, 611 individuals), ecological (42 studied sites) and phenological (281 individuals) variability, supplemented with field observations and a study of relevant herbarium specimens. We found that the studied group is extensively radiated and comprises nine almost allopatric genetic lineages which should be classified at the species or subspecies rank. The C. tuberosus group, as defined here, comprises eight Balkan endemic species, namely C. adamovicii (comb. nov.), C. austrobalcanicus (sp. nov.), C. nissanus, C. orbelicus, C. tuberosus, C. velenovskyi, C. vichrenensis (sp. nov.) and C. vorasanus (sp. nov.). Within C. austrobalcanicus, two subspecies are recognised, namely C. austrobalcanicus subsp. austrobalcanicus (sp. nov. et subsp. nov.) and C. austrobalcanicus subsp. prisadanus (subsp. nov.). An identification key, distribution map and taxonomic treatments of the recognised taxa are provided. [ABSTRACT FROM AUTHOR]

In this paper, we present results of palynomorphological studies of 45 species and 71 specimens of the family Grossulariaceae that are native or cultivated in the Russian Federation and adjacent regions. Pollen was studied with light microscopy, a confocal laser scanning microscope and a scanning electron microscope. Pollen grains of Ribes species are radially symmetrical and isopolar, spheroidal, rarely ellipsoidal and medium-sized (15 to 40 µm). We describe three pollen morphological types in the family: (1) 4-porate type in the subgenus Grossularioides, with echinate mesoporium and atectate exine; (2) 4-7-colporate with 6-12 endopori type in the subgenus Grossularia and the section Heritiera, with psilate, microperforate, rugulate or microechinate mesocolpium and tectate exine; and (3) 4-10-porate-orate type in R. inerme from the subgenus Grossularia and in all other currant taxa except section Heritiera, with psilate or rugulate mesoporium and tectate exine. Pollen data of all studied Ribes species attest to isolation of the family Grossulariaceae based on aperture types and fine pollen morphology; pollen types agree with some taxonomy groups. The content of subgenera and sections and position of some species are discussed. [ABSTRACT FROM AUTHOR]

Apiaceae tribe Scandiceae includes species with diverse fruits that depending upon their morphology are dispersed by gravity, carried away by wind, or transported attached to animal fur or feathers. This diversity is particularly evident in Scandiceae subtribe Daucinae, a group encompassing species with wings or spines developing on fruit secondary ribs. In this paper, we explore fruit evolution in 86 representatives of Scandiceae and outgroups to assess adaptive shifts related to the evolutionary switch between anemochory and epizoochory and to identify possible dispersal syndromes, i.e., patterns of covariation of morphological and life-history traits that are associated with a particular vector. We also assess the phylogenetic signal in fruit traits. Principal component analysis of 16 quantitative fruit characters and of plant height did not clearly separate species having different dispersal strategies as estimated based on fruit appendages. Only presumed anemochory was weakly associated with plant height and the flattening of mericarps with their accompanying anatomical changes. We conclude that in Scandiceae, there are no distinct dispersal syndromes, but a continuum of fruit morphologies relying on different dispersal vectors. Phylogenetic mapping of ten discrete fruit characters on trees inferred by nrDNA ITS and cpDNA sequence data revealed that all are homoplastic and of limited use for the delimitation of genera. Spines evolved from wings developing on secondary ribs. We hypothesize that spines cannot form on primary ribs because these contain vascular bundles that may constrain such a transformation. We describe a new subtribe for Artedia and propose three new combinations in Daucus. [ABSTRACT FROM AUTHOR]

Tropical and subtropical plants provide to pollinators a range of nutritive and non-nutritive materials as alternative to pollen and nectar, including resins, which are gathered by females of several groups of social and solitary bees. Although resin-like material has previously been recorded in Maxillariinae, these investigations generally did not present data relating to pollinators. In fact, the collection of resins has never been recorded elsewhere in orchids. The aim of this paper was to provide a detailed study of the reproductive biology of an Amazonian Heterotaxis, H. superflua, based on records of flowering phenology, floral morphology, pollinator behavior and breeding system. Heterotaxis superflua offers resin-like material to pollinators and is pollinated by a single species of stingless bee. The resin is a heterogeneous material rich in mucilage, starch and sugars, while lipoidal substances occur as small droplets. Chemical analyses confirm the presence of sugar, which explain the presence of reducing sugars and mucilage detected in the histochemical investigations. Our data also showed the Heterotaxis is self-compatible and pollinator dependent. This study demonstrates for the first time the collection of resin-like material in orchids. The gathering of resin is frequently associated with the nest construction, since this material is considered to be a water-repellent and has anti-pathogen chemical properties. Despite offering of a floral reward, fruit set under natural conditions is lower than for experimental pollinations, suggesting limited pollen flow within the population. [ABSTRACT FROM AUTHOR]

Members of Oncidiinae are widely known for their interactions with oil-collecting bees that explore lipophilic secretions on flowers. They may also be pollinated through food deception and the offering of nectar. Although data on breeding systems are available for many Oncidiinae orchids, little is known about the reproductive strategies in Rodriguezia, a neotropical genus of ca. 55 species. In this paper, we explore the reproductive biology of two species of Rodriguezia with distinctive morphologies: R. decora and R. lanceolata. Floral features, spectral reflectance, pollinators and pollination mechanisms, and breeding systems were studied. Both species are scentless and produce nectar as a reward. Floral nectar is secreted by a gland at the base of the labellum and stored into the sepaline spur. Rodriguezia decora reflects mainly in the blue and red regions of the light spectrum, while R. lanceolata reflects in the red region. Rodriguezia decora is exclusively visited and pollinated by butterflies, while Trochilidae hummingbirds are the pollinators of R. lanceolata. Pollinaria attach to the upper third of the proboscis of butterflies (R. decora), and to the bill of hummingbirds (R. lanceolata), during the collection of nectar from the spur. Both Rodriguezia species are self-sterile. Flower features and floral reflectance support the occurrence of psychophily in R. decora and ornithophily in R. lanceolata. [ABSTRACT FROM AUTHOR]

A multivariate morphometric study of the genus Nicoraepoa was carried out to examine patterns of morphological variation among the species and to identify additional characters to allow a clearer delimitation among species. Nicoraepoa is a taxonomically complex genus comprising seven species endemic to South America. Although most of the species are well delimited, two of them, N. andina and N. chonotica, are morphologically similar and very difficult to separate. The morphological variation among species, with overlapping morphological characters, pseudovivipary and possible hybridization make species boundaries unclear. In the present paper, sixty-seven characters were scored for a total of 216 specimens and analyzed using ordination, cluster and discriminant analyses. Based on multivariate results, we recognized species groups and morphological diagnostic characters that allow clearer species delimitation. As a result, N. chonotica has been transferred to N. andina as a subspecies that inhabit southern Patagonia. Other taxa could be recognized and delimited by diagnostic characters: N. erinacea, N. pugionifolia, N. stepparia, N. subenervis subsp. spegazziniana and N. subenervis subsp. subenervis. Moreover, we discuss the possibility that a new species from Bolivia, based on only one specimen, closely related to N. subenervis should be ascribed in Nicoraepoa. [ABSTRACT FROM AUTHOR]

Hybridization has a number of ecological and evolutionary consequences by either increasing intraspecific genetic diversity or by altering morphological characters and secondary chemical content of recombinant individuals. In this paper, we reanalyzed through nSSR and secondary metabolites four mixed stands between Tithonia tubaeformis and T. rotundifolia previously studied with RAPD markers. We amplified nSSR regions to classify individuals in mixed stands as pure or admixed individuals. Then, we explored the chemical profile of each individual in pure and mixed stands by scoring the presence/absence of one abundant flavonoid unique to T. tubaeformis and two sesquiterpene lactones unique to T. rotundifolia. Bayesian analysis of SSR data revealed the presence of pure and admixed individuals in all but one mixed stand, where no pure T. tubaeformis individuals were found. Also, contrary to previous RAPD analysis, we identified a significant number of backcrosses toward T. tubaeformis in two mixed stands. Regarding secondary chemical profiles, pure T. tubaeformis and T. rotundifolia showed characteristic chemical profiles, while admixed individuals showed a mosaic of chemical profiles; some individuals exhibited additivity, while most individuals identified as backcrosses showed dominance. However, some individuals identified as backcrosses toward T. tubaeformis lacked parental compounds, and a new chemical profile was recorded. A new flavonoid (5,3′,4′-trihydroxy-6,7,8-trimethoxyflavanone) was found in these individuals exhibiting the new chemical profile. We suggest that the presence of admixed individuals with novel combinations of secondary metabolites may increase their fitness due to their phytotoxicity and also by the protectant activities against insect herbivores and environmental stress. [ABSTRACT FROM AUTHOR]

Salvia subg. Calosphace (Lamiaceae, Lamiales) is a highly diverse clade endemic to the New World. The phylogenetic relationships of Calosphace have been previously investigated using DNA sequences of nuclear ITS region and plastid psbA- trnH intergenic spacer, but the resulting trees lack resolution and support for many clades. The present paper reassesses the phylogenetic relationships of subgenus Calosphace, including a broader taxon sampling, with a special focus on representing previously unsampled sections, and using an additional plastid marker ( trnL- trnF region). Our results show increased resolution and overall patterns of support, recovering ten main clades. Within core Calosphace, the most inclusive of these main clades, 17 new subclades were identified. Of the 42 sections for which more than one species was analysed, only 12 are monophyletic. Our biogeographical analysis identified at least twelve migrations to South America from Mexican and Central American lineages, in agreement with previous suggestions of multiple origins of South American Calosphace diversity. This analysis also confirmed a colonization of the Antilles by Andean lineages. The reconstruction of ancestral states of pollination syndromes showed multiple shifts to ornithophily from melittophily and one reversal to the latter. [ABSTRACT FROM AUTHOR]

Here we present the third release of the plant rDNA database (March 2017), an open access online resource with information on numbers, locations and structure of 5S and 18S-5.8S-26S (35S) ribosomal DNA (rDNA) (). Data are now available for 2148 species (3783 entries), extracted from 785 papers published until the end of 2016. This means an expansion of 33.5% in terms of new species and 13% in new publications consulted. We appreciate an increased interest on rDNA loci research in recent years, since 10.78% of all data available were published only in 2016. The database has been expanded to include information on telomere composition and on species whose genome has been fully sequenced up to date. Telomere sequence is only known with certainty for 9.60% of species in the database and for 36.79% at the genus level, indicating, potentially, that the consensus plant telomere ( Arabidopsis-type) might not be as extended as previously thought. We have also introduced the taxonomic category order as an additional option for data browsing. Similarly, we have included a new category to indicate the hybrid status of taxa. In addition, we upgraded and/or proofread tabs and links and slightly modified the website for a more dynamic appearance. This manuscript provides a synopsis of these changes and developments. [ABSTRACT FROM AUTHOR]

This paper aims at detecting the relationships between phytogeographical patterns of genera of Chinese endemic seed plants and latitude or climatic factors. The landmass of China was divided into four latitudinal zones, each of c. 8°. Based on a total of 1664 indigenous genera of Chinese endemic seed plants which were grouped into fifteen geographical elements, belonging to three major categories (cosmopolitan, tropical and temperate) and which were absent or present in 28 provinces in China, we analyzed the phytogeographical patterns of genera of Chinese endemic seed plants and detected the relationships between them and main climatic factors. Our results showed that the proportion of tropical genera decreases with the increase in latitude; the proportion of temperate genera increases with the increase in latitude; and the proportion of cosmopolitan genera increased gradually increased gradually with latitude. There are a slow decrease in the proportion of tropical genera and slow increase in the proportion of temperate genera at latitudes 35°-40°. Alternatively, the tropical genera and the temperate genera have the same proportion at latitude c. 25°. These changes and issues about the different genera also appeared in main climate factors. In general, the genera present in a more northerly flora are a subset of the genera present in a more southerly flora. In summary, the large-scale patterns of phytogeography of endemic flora in China are strongly related to latitude, which covary with several climatic variables such as temperature. [ABSTRACT FROM AUTHOR]

The genus Leucheria Lag. (Asteraceae Bercht. and J. Presl, tribe Nassauvieae Cass.) comprises 45 species and three infraspecific taxa distributed in the Andean region from southern Chile and Argentina to Peru. Six species are annual herbs. The genus has had a long taxonomic history involving the transference of species described originally under many different genera. The main objectives of this paper were to determine the phylogenetic relationships of species of Leucheria, examine the hypothesis that the ancestor of Leucheria would have originated in a forested habitat and examine the validity of nine morphologically defined evolutionary lines recognized in earlier work on the genus. Additionally we investigated whether the annual species of Leucheria are derived. We extracted DNA from leaf material for 45 taxa (94%) of Leucheria. We used Bayesian inference and plastid and nuclear genes to construct a phylogenetic hypothesis. Results show that Leucheria is monophyletic and is comprised of two main clades. One clade comprises perennial acaulescent/subacaulescent species, all with a solitary capitulum. We recognized three lineages in the second clade comprised of caulescent species that exhibit multiple capitula. Optimization of life-form over the phylogeny showed that five of the six annual species studied are derived in our tree. We conclude that the appearance of the annual habit is associated with the colonization of arid conditions in the winter rainfall coastal desert of northern Chile. Our result shows that species of Leucheria from forested habitats are derived. Discrepancies with previously recognized morphologically defined evolutionary lines were detected. [ABSTRACT FROM AUTHOR]

This paper describes and illustrates Heteropterys serrata, a new species endemic to semideciduous forests associated with inselbergs in the state of Espírito Santo, Brazil. Morphological and wood anatomical traits of the new species are compared to those of other species of the Heteropterys Metallophyllis informal group. Based on wood anatomy, H. serrata and H. nitida (the most morphologically similar species) have different axial parenchyma, which is scarce paratracheal in H. nitida (and some other species of the Metallophyllis informal group) and aliform confluent in H. serrata. The most notable morphological and anatomical characters that distinguish the new species are the young hexagonal stems, the unusual widely serrate leaf margins and the aliform confluent axial parenchyma in the wood. [ABSTRACT FROM AUTHOR]

In this paper, we report the microspore morphology of 18 species in genus Selaginella P.Beauv. of family Selaginellaceae Willk. from China observed using scanning electron microscopy. Among these species, the morphological characteristics of 17 species have not been reported previously. The results show that the surface ornamentation of microspores of Selaginellaceae can be differentiated into nine major types including granulate, tuberculate, verrucate, verrucate-rugulate, spinate, baculate, reticulate, lamellate and cerebroid. These characteristics as taxonomic basis for subgenus classification support the view of Hieronymus (Die naturlichen pflanzenfamilien. Verlag von Wilhelm Engelmann, Leipzig, ) that genus Selaginella should be classified as two sub-genera Homoeophyllum and Heterophyllum. [ABSTRACT FROM AUTHOR]

Turnera sidoides is a complex of dystilous perennial rhizomatous herbs with five subspecies in which diploid (2 n = 2 x = 14) to octoploid (2 n = 8 x = 56) cytotypes were found. Previous studies have suggested an autopolyploid origin of the complex, and provided evidence for the production of 2 n pollen in experimental conditions as well as in natural populations. However, only the production of 2 n pollen has been demonstrated so far, while the production of 2 n eggs on experimental crosses or in natural populations of T. sidoides remains unknown. In this paper we investigate the production of 2n eggs in diploid individuals to understand how they may have contributed to the origin and establishment of polyploids in diploid populations of T. sidoides. Our progeny test and flow cytometric analysis of seeds collected in natural populations of this species complex, show that the triploid embryos originated from 2n eggs, suggesting that 2n eggs can contribute to the origin of neopolyploids by sexual unilateral polyploidization as well as by sexual bilateral polyploidization. The occurrence of plants that continuously form many 2n eggs and pollen would play a key role in the establishment of neopolyploids in natural diploid populations. [ABSTRACT FROM AUTHOR]

This paper presents a taxonomic revision of species of the genus Sobralia (Orchidaceae) in the Guyanas (Guyana, Suriname & French Guiana) based on an extensive study of herbarium material. Descriptions of their morphology, ecology and distribution are included and supported by illustrations of their habits and floral parts. A determination key is provided. Sobralia agnieszkae Baranow and Sobralia romeroana Baranow & Szlach.-two new species of the genus discovered among material collected in Guyana-are described. Including the newly described taxa, 14 species of the genus occur in the study area and, based on literature data, two further species ( S. crocea (Poepp. & Endl.) Rchb.f. and S. fimbriata Poepp. & Endl.) are expected to be found there. [ABSTRACT FROM AUTHOR]

This paper presents results of examination of fruit surface in the genus Lamium L. (Lamiaceae) using scanning electron microscopy (SEM). The purpose of this study was to define new features that differentiate taxa difficult to identify on the basis of macromorphological features, such as species of hybrid origin and subspecies within Lamium. The results of our research show that the SEM analysis of fruit surface allowed defining new diagnostic features for almost all studied representatives of the genus Lamium except for L. confertum from L. coutinhoi and L. album subsp. album from L. album subsp. barbatum. The most useful feature in distinguishing the examined species was cuticle striation. I turn, the type of secondary sculpturing of the cell walls divided the species studied into two main groups. One of them consisted of four taxa ( L. album, L flexuosum, L. garganicum, L. orvala) with thickenings of the cell walls in the form of irregular ridges and tubercles. The other one comprised all the remaining species, with cell wall thickenings forming regular papillae. The only species which could not be qualified to any of these groups was L. moschatum. The obtained results demonstrated also high similarity of L. galeobdolon to the remaining species of Lamium, especially L. flexuosum and L. orvala. This observation provides an argument for the inclusion of L. galeobdolon to the genus Lamium. [ABSTRACT FROM AUTHOR]

Phellinus piptadeniae (Hymenochaetaceae, Hymenochaetales) as currently accepted is characterized by having applanate to ungulate basidiome with the pilear surface concentrically sulcate, radially cracked in old specimens, and a sinuous black line in the context. The species has been recorded in seasonally dry forests of different Brazilian domains, often associated with legume hosts. It occurs highly specifically associated with Piptadenia gonoacantha in semideciduous forest of the Atlantic Forest domain in southeastern Brazil. In the Caatinga dry woodlands, northeastern Brazil, Phellinus piptadeniae occurs as host recurrent of different Piptadenia species. During recent polypore surveys, specimens that are morphologically similar to the type were collected in seasonally dry tropical forests (SDTFs) of northwestern Peru also on legume hosts ( Libidibia glabrata and Pithecellobium excelsum). In this paper, we discuss the morphological variation, host range, and distribution of Phellinus piptadeniae in the context of the historical biogeography of the neotropical SDTF biome. Some taxonomic implications that should be further investigated in a molecular phylogenetic framework are also addressed. [ABSTRACT FROM AUTHOR]

The patterns of relationships between species of Opuntia from southern South America are scarcely known in spite of the importance of this region as a diversification center for the Cactaceae. This paper contributes to the better understanding of the genetic and phylogenetic relationships of 15 Opuntia species from Argentina, Bolivia, Brazil, Paraguay, and Uruguay by generating new genetic data through Inter-Simple Sequence Repeat (ISSR) genotyping and the sequencing of plastid intergenic spacers trnL- trnF and psbJ- petA. The species surveyed are: O. anacantha, O. arechavaletae, O. aurantiaca, O. bonaerensis, O. colubrina, O. discolor, O. elata, O. megapotamica, O. monacantha, O. penicilligera, O. quimilo, O. salmiana, O. schickendantzii, O. sulphurea, and O. ventanensis. The genetic distance-based analysis of 110 ISSR bands, applying the Neighbor-Joining and NeighborNet algorithms, evidenced considerable intraspecific variation in O. aurantiaca, O. elata, O. discolor, and O. salmiana. The emergent clustering pattern and the species assignment to taxonomic series show a general agreement for Armatae and Aurantiacae. The phylogenetic relationships were investigated via haplotype network and maximum likelihood approaches, within a broader sampling that involves most species currently accepted for South America, and samples from throughout the American continent. Hence, 15 haplotypes are recognized for southern South American opuntias whereas eight haplotypes are established for Northern Hemisphere opuntias. Biparentally and maternally inherited genetic data yield partially consistent results, giving genetic support for morphologically defined taxonomic series. [ABSTRACT FROM AUTHOR]

Turnera sidoides is a complex of outcrossing, perennial, rhizomatous herbs that is widely distributed in southern South America. Five subspecies are recognized taxonomically based on morphological features and geographical distribution. In certain regions, the areas of distribution of the subspecies overlap partially. In such contact zones, the extent of reproductive barriers among subspecies is still largely unknown, but morphologically intermediate individuals have been found in the field, indicating that hybridization may actually occur between subspecies. Crossability among subspecies of T. sidoides has been shown by experimental studies with cultivated plants, but the mechanisms involved in natural populations are still unknown. To investigate the mechanisms that underlie gene flow within the T. sidoides complex, in this paper we analyze the morphological and genetic variation, as well as the crossability among taxa in a contact zone between subspecies pinnatifida and sidoides, in southeastern Uruguay. Our results constitute the first evidences of ongoing natural hybridization between subspecies of T. sidoides and suggest that, although hybridization may not have been of significance in the early phase of the species differentiation, reticulate evolution is ongoing enhancing the current morphological and genetic variability of the complex. [ABSTRACT FROM AUTHOR]

This paper reports on phenology, breeding system and dependence on pollinators of two sympatric Dichorisandra species. Dichorisandra incurva is a chamaephyte with continuous growth and precocious flowering, whereas D. hexandra is a geophyte with seasonal growth and delayed flowering. Flowering and fruiting occur mainly in the wet season; thus moisture can be important for both species. Besides moisture, photoperiod seems also to be related to the flowering only of D. incurva. Flowers of both species are poricidal, oligandrous, zygomorphic and buzz-pollinated by Apidae and/or Halictidae bees. Dichorisandra incurva is self-compatible, while D. hexandra shows a late-acting self-incompatible system. Moreover, herkogamy and poricidal anthers prevent spontaneous self-pollination in D. incurva. Therefore, medium- to large-sized Apidae are the most suitable pollinators as they make regular contact with anthers and stigmas and are further known to perform trapline foraging. This behaviour is particularly important for D. hexandra where Halictidae are considered pollen robbers, thus wasting pollen which, consequently, causes low reproductive efficacy in this species. Nevertheless, bee diversity is probably advantageous for the reproductive success of both Dichorisandra species. While the efficiency of each bee species is not known, further studies will show whether additional benefits are gained from the maintenance of these interactions. [ABSTRACT FROM AUTHOR]

The diversity of the Neotropical subtribe Cranichidinae comprising mostly terrestrial orchids is still discussed by numerous taxonomists. The actual number of species classified in the genera of this group seems to be underestimated in the light of the recent revisions of the herbarium material. In this paper the taxonomic affinities of three controversial species considered as representatives of Cranichis: Pseudocranichis thysanochila, Ocampoa mexicana and Exalaria parviflora are discussed. Three new combinations, one within Pseudocranichis and two within Ocampoa are proposed. Results of the taxonomic revision of Colombian Cranichis are presented together with a key to the national representatives of the genus. [ABSTRACT FROM AUTHOR]

Opuntia, commonly named 'nopal' in Mexico, is an important crop for its agronomical, economical, ecological and cultural value. Furthermore, it is known for its taxonomic complexity. In this paper, we report the genetic variability of 52 Opuntia cultivars with agronomic and economic importance, classified into 12 different species using random amplified polymorphic DNA (RAPD) and inter-simple sequence repeats (ISSR) markers. Ten primers, five for each marker type, were selected to assess their ability to detect polymorphisms in this plant accesions/varieties. Both marker systems generated a total of 307 bands, of which 50.8 % were polymorphic with an average of 15.6 polymorphic bands per primer. Thus, we assume that Mexican Opuntia varieties present broad genetic variation. Based on percentage of polymorphic bands; resolving power; polymorphic information content; and Marker Index, the K-12 (RAPD) and IS-06 (ISSR) primers were the most informative ones. Clusters obtained from RAPD, ISSR and a combination of both data sets did not match the actual taxonomic classification. On the other hand, the putative varieties currently classified in the same species were not located in the same cluster. Besides, the varieties included in O. ficus- indica, O. albicarpa and O. megacantha showed broad variation but were not well defined into separate clades; these cultivars possibly have common ancestry. The results presented here support our hypothesis about the existence of a smaller number of Opuntia species in accordance with those currently described, but with high intraspecific genetic variation. [ABSTRACT FROM AUTHOR]

Pollen grains of 450 samples of 25 species of the genus Orobanche and Phelipanche occurring in Central Europe were investigated using light and scanning electron microscopy. Palynological data on 18 species are reported here for the first time. The usefulness of micromorphological studies on pollen of Orobanche and Phelipanche is demonstrated. Previous research showed the separation of Phelipanche from Orobanche, a finding which is also supported by pollen aperture type and exine ornamentation. The pollen of Phelipanche is tricolpate, while that of Orobanche is inaperturate. Our research showed that one of the species included so far within Orobanche, namely O. coerulescens, has tricolpate pollen with microreticulate sculpture. As a consequence of the finding of tricolpate pollen and intermediate macromorphological characteristics of this species between Orobanche and Phelipanche, it is proposed to transfer it to a new genus, Orobanchella, described in the paper. A comparison of the main characteristics distinguishing Orobanche, Phelipanche, Boulardia and Orobanchella is also presented and discussed. [ABSTRACT FROM AUTHOR]

In this paper we document Fagaceae pollen from the Eocene of western Greenland. The pollen record suggests a remarkable diversity of the family in the early Cenozoic of Greenland. Extinct Fagaceae pollen types include Eotrigonobalanus, which extends at least back to the Paleocene, and two ancestral pollen types with affinities to the Eurasian Quercus Group Ilex and the western North American Quercus Group Protobalanus. In addition, modern lineages of Fagaceae are unambiguously represented by pollen of Fagus, Quercus Group Lobatae/Quercus, and three Castaneoideae pollen types. These findings corroborate earlier findings from Axel Heiberg Island that Fagaceae were a dominant element at high latitudes during the early Cenozoic. Comparison with coeval or older mid-latitude records of modern lineages of Fagaceae shows that modern lineages found in western Greenland and Axel Heiberg likely originated at lower latitudes. Further examples comprise (possibly) Acer, Aesculus, Alnus, Ulmus, and others. Thus, before fossils belonging to modern northern temperate lineages will have been recovered from older (early Eocene, Paleocene) strata from high latitudes, Engler's hypothesis of an Arctic origin of the modern temperate woody flora of Eurasia, termed 'Arcto-Tertiary Element', and later modification by R. W. Chaney and H. D. Mai ('Arcto-Tertiary Geoflora') needs to be modified. [ABSTRACT FROM AUTHOR]

The Neotropical subtribe Pachyphyllinae comprises orchids distributed mainly along the Andes and characterized by the monopodial type of growth. The systematic position of this taxon within Orchidaceae and its generic composition was intensively discussed, but so far no comprehensive morphological study on the group was conducted. In this paper the morphological descriptions of all genera included in Pachyphyllinae are provided and the key to their identification is presented. In addition, the taxonomic position of Raycadenco is discussed. The research revealed the existence of two distinctive species which were classified until now within Pachyphyllum or Fernandezia. Since neither the flower morphology of those two species nor the gynostemium structure fulfils the concept of any known orchid taxon, the new genus is described here under the name Valdiviesoa. The two representatives of the new taxon are illustrated and the photographs of the plants are provided. The information about their distribution and ecology are provided. The morphological characters of all Pachyphyllinae representatives are compared. [ABSTRACT FROM AUTHOR]