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This paper presents the karyotype and DNA content of 12 diploid species of Hippeastrum from South America. The variation in genome size is compared with the karyotype and DNA content of Amaryllis belladonna from South Africa. The Hippeastrum species present a uniform and bimodal basic karyotype formula, but significant differences are found in the total chromosome volume (TCV) and nuclear DNA content. A positive correlation between the DNA content and TCV is also observed. The karyotype’s constancy is a product of changes in DNA content occurring in the whole chromosome complement. The DNA addition to the long and short sets of chromosomes varies independently. In species with higher DNA contents, the short chromosomes add equal DNA amounts to both arms, maintaining their metacentric morphology, whereas the long chromosomes add DNA only to the short arm, increasing the chromosome symmetry. These data show that the evolutionary changes in DNA amount are proportional to chromosome length, maintaining the karyotypic uniformity. A. belladonna has a larger DNA content and possesses a karyotype different from that of Hippeastrum spp., supporting the distinction between the two genera and upholding the name Amaryllis for the South African entity against Hippeastrum for the South American genus. © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society, 2007, 155, 171–178. [ABSTRACT FROM AUTHOR]

Minthostachys (Benth.) Spach (Labiatae) is a South American genus of aromatic shrubs frequently collected as a condiment, for the preparation of tea, or for medicinal purposes. Notoriously difficult species delimitation, conflicting taxonomic treatments of the past, and the lack of a revision with modern methods have hampered the understanding of this ecologically and economically interesting group. The amplified fragment length polymorphism (AFLP) study presented in this paper supplements field and morphological studies within the framework of a taxonomic and systematic revision. AFLP is found to be unsuitable for the reconstruction of the phylogeny of Minthostachys. Although, in some cases, morphologically well-defined species are also genetically distinct, extensive gene flow seems to occur between strikingly different species growing in the immediate vicinity and even between Minthostachys and Clinopodium ( Xenopoma) vanum. Samples from the most complicated species, M. mollis, are genetically very heterogeneous and mostly fall into two clusters according to their geographical origin, exhibiting a high discrepancy with the pattern of morphological variation. © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society, 2007, 153, 9–19. [ABSTRACT FROM AUTHOR]

Wild intergeneric hybrids are recorded among six genera in the New Zealand Gnaphalieae, but little evidence substantiating their identity has been published. In this paper we evaluate the identity of putative hybrids between two species of Gnaphalieae endemic to New Zealand, Anaphalioides bellidioides and Ewartia sinclairii. The two species are occasionally sympatric in the north-east of the South Island and wild putative hybrids are rarely encountered. To test the hybridity hypothesis, specimens from nine putative hybrids were collected from one site and analysed for 76 morphological characters. The putative hybrids possessed predominantly intermediate or parental character states in comparison with A. bellidioides and E. sinclairii. Extreme traits were less common and a single novel character state was recorded in two hybrids only. Non-metric multidimensional scaling of dissimilarities derived from both continuous and discrete characters was strongly supportive of the hybridity hypothesis. Canonical discriminant analysis of the continuous characters was supportive for some putative hybrids only, in part reflecting the possession of extreme states in characters with high loadings. One of the putative hybrids was strongly indicated to be a backcross with A. bellidioides. The taxonomic treatment of cross-compatible genera is discussed. [ABSTRACT FROM AUTHOR]

Meiotic and mitotic chromosomes of 13 species of Salvia from Argentina were studied. Most of our data are new counts but some, mainly from cultivated species, confirm previous reports or represent numbers which are different from those cited previously. Only Salvia gilliesii Benth, and the introduced species S. coccinea Juss., S. farinacea Benth., S. involucrata Cav. and S. microphylla Kunth are diploids. S. cardiophylla Benth., S. procurrens Benth., S. splendens Roem. & Schult. and S. uliginosa Benth. are tetraploids; S. stachydifolia Benth. is hexaploid; and S. guaranitica A. St.-Hil., S. pallida Benth. and S. rypara Briq. are octoploids. The basic number most frequently found is x = 11, but two species, S. procurrens and S. uliginosa, have x = 13. S. farinacea has x = 10 but this species is a widespread cultivated plant, not native in this area. Seven of the studied species showed one to three B chromosomes. We discuss some systematic and evolutionary aspects of the genus in the light of the cytogenetic data, the relationships between geographical distribution and chromosome numbers in relation to levels of ploidy and basic chromosome numbers, and make comparisons with some of the different taxonomic sections. [ABSTRACT FROM AUTHOR]

Aiming to shed light on the influence of Pleistocene geoclimatic events on the current genetic patterns in the flora of the South American Chaqueño Phytogeograpic Domain, we performed phylogeographic and Bayesian ancestral area reconstruction analyses based on plastid DNA sequences of Turnera sidoides. Lineages started to diversify 2.02 Mya, forming two major clades, one comprising extant populations from the western boundary and the other including populations from the eastern boundary of the distribution of T. sidoides. Major divergences within clades occurred at two years 1.44 and 1.72 Mya. Ancestral area reconstruction analyses suggest a western origin of T. sidoides in the Peripampasic Arc. Our results support the hypothesis that Pleistocene geoclimatic events in the Chaqueño Domain played an important role in shaping genetic variation. The establishment of the Arid Diagonal acted as a barrier to gene flow between the western and eastern populations during the Pleistocene Patagonian Glaciations. After this period, the orogeny of the region and Pleistocene climatic oscillations played a role in the divergence of isolated ancestral populations followed by migrations to the Chaco-Pampa plain. [ABSTRACT FROM AUTHOR]

Many factors influence leaf anatomy and morphology in the crown of a tree, particularly those resulting from microclimatic differences between the periphery and the interior of the crown. These influences can be so strong that single species can produce different leaf forms in which shade and sun leaves exhibit consistently distinctive morphological and epidermal character sets. Here we show, using Liquidambar as a model system, that the principal morphological characters for distinguishing shade and sun leaves in two modern Liquidambar spp. with different lamina types (entire in L. chinensis and lobate in L. formosana) are the leaf lamina length to width ratio, the degree of development of venation networks, tooth size and tooth shape. The main epidermal characters are ordinary cell size and anticlinal wall outlines. Many fossils, however, are only preserved as impressions and morphological characters alone have been used to distinguish shade and sun leaf morphotypes. To evaluate the utility of our approach, populations of fossil Liquidambar leaves from the Eocene of southern China, preserved only as impressions, were categorized into sun and shade morphotypes. Recognition that sun and shade leaf morphological diversity exists in fossil populations will enable palaeobotanists to identify more reliably foliar polymorphisms that would otherwise be used to describe, incorrectly, different species. [ABSTRACT FROM AUTHOR]

The Lotus corniculatus complex (Fabaceae, Loteae) includes diploids (2 n = 2 x = 12) and tetraploids (2 n = 4 x = 24). Monophyly of the complex was supported by recent phylogenetic analyses, but evolutionary relationships within it remain debatable. The present study aims to outline species relationships in the L. corniculatus complex and evolutionary history of the group in eastern Europe and northern Asia. Genetic variability (based on plastid trnL – trnF sequences and eight nuclear microsatellite loci) is described for 51 local populations of six species in the complex (the diploids L. krylovii, L. frondosus, L. tenuis and L. stepposus and the tetraploids L. corniculatus and L. × ucrainicus) in northern Eurasia and compared to the patterns of morphological differentiation. A representative set of species of Lotus section Lotus was also included in phylogenetic and phylogeographic analyses. The morphological and genetic variation patterns indicate sporadic interspecific hybridization in sympatric zones. The genetic structure of the species is different in the European and Asian parts of the distribution area. Taxonomic significance of indels in the trnL-F region is confirmed by phylogenetic studies of section Lotus. A reconstructed plastid haplotype network of the L. corniculatus group indicated that haplotype A is closest to the hypothetical ancestral type in one of the Mediterranean glacial refugia. The proposed phylogeographic scenario suggests a European origin of the L. corniculatus complex and its geographical expansion parallel to the changes in plastid haplotypes from group A in Western Europe to group D in Central Asia, as well as the existence of a possible ‘southern’ lineage represented by the haplotype E group. The decrease of population genetic variability in Asia is probably due to the change of prevailing mating system from cross-pollination to autogamy. [ABSTRACT FROM AUTHOR]

Extensive phylogeographic and population studies in Nothofagus revealed that hybridization, introgression and plastid capture are common phenomena that have occurred throughout the evolutionary history of the genus. Here, detailed karyotypes of ten South American Nothofagus spp. were constructed using chromosome fluorescent banding with the aim of (1) investigating if karyotype features were compatible with the formation of fertile interspecific hybrids, particularly when growing in sympatry and (2) identifying species-specific chromosomal markers to enable further studies of hybridization in Nothofagus. Similar karyotype formulas and heterochromatin patterns among species of the same clade (i.e. subgenus) revealed a low rate of chromosomal change. This finding reinforces the idea that hybrids between Nothofagus spp. can be fertile and that chromosome pairing in meioses could be successful. Genome conservation and extensive hybridization that resulted in plastid capture has been observed in other woody genera. Hybridization in tree species could be a survival strategy to enable the successful colonization of sites after disturbance and the introgression of genes from their congeners (adaptive introgression) may play an important role in adapting to climate change. Finally, N. antarctica has one more nucleolus organizing region (NOR) than its congeners that is easily identifiable and therefore could be used in future studies of hybrids. [ABSTRACT FROM AUTHOR]

Genetic diversity and population structure in plants are directly associated with the reproductive system and gene flow by pollen and seeds. We examined the reproductive system, pollination biology, genetic diversity and structure, and gene flow in Bromelia hieronymi , an endemic species of the humid Brazilian chaco. We characterized the reproductive system by hand-pollination experiments and the pollination biology by observations, both in situ. For the genetic analysis we used nuclear and plastid microsatellite markers. Bromelia hieronymi is allogamous, self-incompatible and clonal. The potential pollinators were hawkmoths and hummingbirds, but butterflies were also observed. The three populations studied showed high levels of genetic diversity for nuclear (mean observed and expected heterozygosity H O = 0.624 and H E = 0.558) and plastid markers (mean H E = 0.688) and moderate genetic structure (fixation index F ST = 0.138); we found evidence of genetic bottlenecks in two populations. The self-incompatibility system may have a strong relationship with gene flow, and its association with clonality may be responsible for the high genetic diversity observed. Gene flow by seeds was more efficient than gene flow by pollen. These results show that B. hieronymi responds negatively to reduction in population size. Therefore, continuous conservation strategies are necessary to avoid increasing genetic differentiation in the species, maintaining its evolutionary potential for adaptation. [ABSTRACT FROM AUTHOR]

To better understand the responses of arid-adapted, alpine plants to Quaternary climatic oscillations, we investigated the genetic variation and phylogeographic history of Orinus, an endemic genus of Poaceae comprising three species from the dry grasslands of the Qinghai-Tibet Plateau (QTP) in China. We measured the genetic variation of 476 individuals from 88 populations using three maternally inherited plastid DNA markers (matK, rbcL and psbAtrnH), the biparentally inherited nuclear ribosomal internal transcribed spacer (nrITS) and amplified fragment length polymorphisms (AFLPs). We found that the plastid DNA, nrITS and AFLPs show considerable, recent differentiation among the species. We detected 14 plastid haplotypes (H1-H14), of which only three were shared among all species, and 30 nrITS ribotypes (S1-S30), of which one (S10) was shared between two species, O. kokonoricus and O. intermedius, but absent in O. thoroldii. The nrITS types formed clades that were inconsistent with species boundaries. Based on these data, we propose and illustrate a complex hypothesis for the evolutionary history of Orinus involving lineage sorting and introgression, the latter of which may explain the shared S10 nrITS type. The AFLP results showed clades corresponding to current species delineation and suggest that lineage sorting in the genus is probably complete. We estimated the crown age of Orinus to be 2.85 (95% highest posterior density: 0.58-12.45) Mya (late Pliocene), and subsequent divergence occurred in the Quaternary. Early divergences were allopatric. More recently, Orinus probably underwent regional expansions corresponding to Quaternary climatic changes, especially glaciation, which is consistent with our divergence time estimates. These climatic changes could have facilitated the S10 event and other hybridization events. Our data also suggest that species of this small genus of grasses survived the Quaternary glacial period in the extremely adverse habitats of the QTP. [ABSTRACT FROM AUTHOR]

The taxonomic status and phylogenetic position of three pyrogenic geofrutex members of Rubiaceae confined to grassland or savannah in central and southern Africa are clarified. Eriosemopsis, represented by E. subanisophylla, is a monotypic genus endemic to South Africa. Although morphologically clearly a member of tribe Vanguerieae (Rubiaceae), its exact phylogenetic placement was hitherto unknown. Using five molecular markers, we confirmed the separate generic status of Eriosemopsis and demonstrated that it is part of the Canthium group, closely related to Pygmaeothamnus chamaedendrum. This last species is shown not to be closely related to Pygmaeothamnus zeyheri, the type species of Pygmaeothamnus, and is therefore transferred to a new monotypic genus, namely Bridsonia. Recognition of Bridsonia chamaedendrum also renders Pygmaeothamnus monotypic. Illustrations of all three species involved and a distribution map for B. chamaedendrum are provided. [ABSTRACT FROM AUTHOR]

Deschampsia antarctica is the only grass naturally occurring in Antarctica, and it is also indigenous to southern South America. We aimed to evaluate patterns of within-population genetic diversity and between the focal areas Patagonia and Antarctica by using 144 sequences of nuclear internal transcribed spacer and non-coding plastid regions. We analysed phylogenetic relationships between these two main areas and performed demographic and landscape analysis. To test the divergence time between Antarctic and Patagonian populations we used approximate Bayesian computation. We found 17 nuclear and eight plastid haplotypes. For both molecular markers, Patagonia was the most genetically variable area in the range of D. antarctica. The divergence time between populations from Antarctica and Patagonia was dated to the mid to late Pleistocene. The large number of private haplotypes found in Patagonia and the great genetic variability support the hypothesis of a South American origin of the Antarctic populations of D. antarctica. Finally, we suggest that D. antarctica probably survived the Last Glacial Maximum and possibly earlier glaciations in ice-free refugia in Patagonia and Antarctica. Dispersal to Antarctica possibly occurred in the mid to late Pleistocene through bird-aided long-distance transport from South America. [ABSTRACT FROM AUTHOR]

We used data from 12 allozyme loci for two endemic Brassicaceae from Gran Canaria (the endangered narrow endemic Crambe tamadabensis and its more widespread congener C. pritzelii) to assess whether their genetic diversity patterns reflect their phylogenetic closeness and contrasting population sizes and distribution areas, and to derive conservation implications. Genetic diversity values are high for both species and slightly higher in C. tamadabensis, despite its narrow distribution in north-western Gran Canaria. At odds with the generally high interpopulation diversity levels reported in Canarian endemics, values of GST in C. tamadabensis and C. pritzelii are rather low (0.067 and 0.126, respectively). We construe that the higher genetic structure detected in C. pritzelii is mainly a result of unbalanced allele frequencies and low population sizes at the edges of its distribution. The overall high allozyme variation detected in C. tamadabensis and C. pritzelii is nevertheless compatible with an incipient but consistent genetic differentiation between the two species, modulated by recurrent bottlenecks caused by grazing and drift. Our data suggest that conservation efforts aimed at maintaining the existing genetic connectivity in each species and ex situ conservation of seeds are the best strategies to conserve their genetic diversity. [ABSTRACT FROM AUTHOR]

Phaedranassa schizantha (Amaryllidaceae) is an endangered species endemic to Ecuador and two varieties have been described: P. schizantha var. schizantha and P. schizantha var. ignea. We assessed population genetic structure and demographic patterns in 11 populations across the range of the species using 13 microsatellite loci. Our data show that genetic diversity was generally lower in the southern part of the range and was especially low in populations closest to cities. We found significant population differentiation ( FST = 0.14, DEST = 0.34) and evidence of a genetic bottleneck. Genetic variation did not show isolation by distance. Instead, results suggest genetic barriers around two main cities. Bayesian analysis identified two genetic groups, neither of which represents either of the two varieties previously recognized. Coalescent analysis indicates a relatively recent colonization pattern between the two genetic groups (< 3000 generations). Conservation efforts need to be taken to facilitate genetic exchange between the groups, especially between locations that seem to be genetically isolated. [ABSTRACT FROM AUTHOR]

The increase in gene diversity from high to low latitudes is a widely recognized biogeographical pattern, often shaped by differential effects of Late Quaternary climatic changes. Here, we evaluate the effects of Pleistocene climatic changes from northern Europe to North Africa and their implications on the population differentiation of the widespread, short-lived herb P lantago coronopus. We used amplified fragment length polymorphism to investigate the population structure and phylogeography of P . coronopus in 273 individuals from 29 populations covering its complete latitudinal range. Although Bayesian clustering, principal coordinates analysis and a consensus UPGMA tree were not fully congruent, two well-supported clades, associated with distinct latitudinal zones (northern Europe and the Mediterranean region), were revealed as a general pattern. Moreover, populations from the western Atlantic edge and, to a lesser extent, the central Mediterranean region exhibited signs of admixture, suggesting secondary contacts. The admixed populations in the western Atlantic and central Mediterranean are geographically intermediate between the northern and southern lineages. The northernmost lineage exhibited low genetic diversity, a clear sign of a recent colonization. In contrast, populations from the southernmost part of the range showed the highest level of genetic diversity, indicating possible refugia for the species during the Quaternary ice ages. Overall, our study allows spatial structure of the genetic variation of a widespread herb across its latitudinal range to be disentangled and provides insights into how past climatic history influences present genetic patterns. © 2015 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 179, 618-634. [ABSTRACT FROM AUTHOR]

The development of spatial genetic structure ( SGS) in seed plants has been linked to several biological attributes of species, such as breeding system and life form. However, little is known about SGS in ferns, which together with lycopods are unique among land plants in having two free-living life stages. We combined spatial aggregation statistics and spatial genetic autocorrelation analyses using five plastid microsatellites and one nuclear gene to investigate SGS in two populations of the outcrossing tree fern Alsophila firma ( Cyatheaceae). We assessed how the observed patterns compare with those estimated for other ferns and seed plants. Populations of A. firma exhibited strong SGS, spatial clustering of individuals, substantial clonal diversity and no inbreeding. SGS in ferns appears to be higher than in most seed plants analysed to date. Contrary to our expectations, an outcrossing breeding system, wind dispersal and an arborescent life form did not translate into weak or no SGS. In ferns, SGS is probably being affected by the life cycle with two free-living life stages. The reproductive biology of ferns appears to be more complex than previously thought. This implies that SGS in ferns is affected by some factors that cannot be inferred from the study of flowering plants. © 2015 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 177, 439-449. [ABSTRACT FROM AUTHOR]

We used plastid sequences ( trn L, trn L-trn F, pet N- psb M and trn T- trn L) to infer the phylogenetic relationships and inter-island connections of the Canarian Juniperus cedrus, and AFLP fingerprints to assess its genetic diversity patterns. Maximum Likelihood, Maximum Parsimony and Bayesian methods suggest independent colonization events for the three Macaronesian junipers and support the monophyly of J. cedrus. Plastid sequences reveal a low genetic diversity (three haplotypes) and do not provide sufficient information to resolve its temporal and geographical origin. AFLPs indicate a greater isolation in J. cedrus than in other Macaronesian trees with similar distributions and dispersal syndromes. Gran Canaria harbours the least genetically diverse population, which justifies immediate conservation actions. This island and Tenerife also show independent genetic structure, meaning that genetic exchange from other islands should be avoided in eventual reinforcements. Populations from La Palma and La Gomera show the highest genetic diversity levels and number of polymorphic AFLPs, probably because a lower incidence of felling has allowed a less dramatic influence of genetic bottlenecks. We suggest that management efforts should prioritize populations from these islands to preserve the evolutionary potential of the species, but we also stress the importance of knowledge of the evolutionary history, genetic structure and ecological interactions in conservation strategies. © 2014 The Linnean Society of London, Botanical Journal of the Linnean Society, 2014, 175, 376-394. [ABSTRACT FROM AUTHOR]

The phylogenetic structure of Asclepiadoideae ( Apocynaceae) has been elucidated at the tribal and subtribal levels in the last two decades. However, to date, the systematic positions of seven Asian genera, Cosmostigma, Graphistemma, Holostemma, Pentasachme, Raphistemma, Seshagiria and Treutlera, have not been investigated. In this study, we examine the evolutionary relationships among these seven small enigmatic Asian genera and clarify their positions in Asclepiadoideae, using a combination of plastid sequences of rbc L, rps16, trn L and trn L- F regions. Cosmostigma and Treutlera are resolved as members of the non- Hoya clade of Marsdenieae with strong support (maximum parsimony bootstrap support value BSMP = 96, maximum likelihood bootstrap support value BSML = 98, Bayesian-inferred posterior probability PP = 1.0). Pentasachme is resolved as sister of Stapeliinae to Ceropegieae with moderate support ( BSMP = 64, BSML = 66, PP = 0.94). Graphistemma, Holostemma, Raphistemma and Seshagiria are all nested in the Asclepiadeae- Cynanchinae clade ( BSMP = 97, BSML = 100, PP = 1.0). The study confirms the generally accepted tribal and subtribal structure of the subfamily. One exception is Eustegia minuta, which is placed here as sister to all Asclepiadeae ( BSMP = 58, BSML = 76, PP = 0.99) and not as sister to the Marsdenieae + Ceropegieae clade. The weak support and conflicting position indicate the need for a placement of Eustegia as an independent tribe. In Asclepiadeae, a sister group position of Cynanchinae to the Asclepiadinae + Tylophorinae clade is favoured ( BSMP = 84, BSML = 88, PP = 1.0), whereas Schizostephanus is retrieved as unresolved. Oxystelma appears as an early-branching member of Asclepiadinae with weak support ( BSMP = 52, BSML = 74, PP = 0.69). Calciphila and Solenostemma are also associated with Asclepiadinae with weak support ( BSMP = 37, BSML = 45, PP = 0.79), but all alternative positions are essentially without support. The position of Indian Asclepiadoideae in the family phylogeny is discussed. © 2014 The Linnean Society of London, Botanical Journal of the Linnean Society, 2014, 174, 601-619. [ABSTRACT FROM AUTHOR]

Studies of ecological and phenotypic diversity in adaptive radiations have greatly contributed to our understanding of the patterns and processes of species diversification, whilst also challenging our assessment of the nature of species. Here, analyses of bioclimatic, molecular and morphological data, interpreted in phylogenetic and geographical contexts, were carried out to understand species limits in the Madagascar olive ( Noronhia, Oleaceae). Most species hypotheses exhibit clear boundaries and are supported by at least one line of evidence, but a contrasting pattern of high morphological and ecological variation with relatively low nucleotide sequence divergence characterizes the diversification of Noronhia. This diversification was probably driven by fine-scale ecological and evolutionary processes, as suggested by the poor fit with four models of species diversification of the biota of Madagascar and the apparent lack of differentiation detected from large-scale bioclimatic data. Overall, this study offers useful insights into the patterns of plant diversification in Madagascar, the understanding of which requires good circumscription of species, improved knowledge of their distribution and operational models of diversification that take into account the particular biology of plants. © 2013 The Linnean Society of London, Botanical Journal of the Linnean Society, 2014, 174, 141-161. [ABSTRACT FROM AUTHOR]

The Iberian mountain spiny fescues are a reticulate group of five diploid grass taxa consisting of three parental species and two putative hybrids: F. × souliei ( F. eskia × F. quadriflora) and F. × picoeuropeana ( F. eskia × F. gautieri). Phenotypic and molecular studies were conducted with the aim of determining the taxonomic boundaries and genetic relationships of the five taxa and disentangling the origins of the two hybrids. Statistical analyses of 31 selected phenotypic traits were conducted on individuals from 159 populations and on nine type specimens. Molecular analyses of random amplified polymorphic DNA ( RAPD) markers were performed on 29 populations. The phenotypic analyses detected significant differences between the five taxa and demonstrated the overall intermediacy of the F. × picoeuropeana and F . × souliei between their respective parents. The RAPD analysis corroborated the genetic differentiation of F. eskia, F. gautieri and F. quadriflora and the intermediate nature of the two hybrids; however, they also detected genetic variation within F. × picoeuropeana. These results suggest distinct origins for F. × picoeuropeana in the Cantabrian and Pyrenean mountains, with the sporadic Pyrenean populations having potentially resulted from recent hybridizations and the stabilized Cantabrian ones from older events followed by potential displacements of the parents. © 2013 The Linnean Society of London, Botanical Journal of the Linnean Society, 2013, 173, 676-706. [ABSTRACT FROM AUTHOR]

Iterophyllum lobatum gen. et sp. nov. is reported from the late Barremian lithographic limestones of Las Hoyas, Spain. It consists of a simple, petiolate leaf, with a pinnately lobed lamina. The dentate thickened margin bears chloranthoid-like glands at lobe apices and sinuses. The venation is pinnate and craspedodromous, with three discernible vein orders. Based on the low regularity of vein course and angles and the low leaf rank, such a venation pattern may represent an early evolved leaf archetype in early basal eudicots. An acropetal leaf development mode in I. lobatum is similar to that in several living Papaveraceae. The leaf architecture and ecophysiology, particularly the vein widths and the glands, indicate that I. lobatum leaves were aerial. The plant grew close to water in the wetland terrestrial ecosystem of Las Hoyas. Iterophyllum lobatum might have been an opportunist species in early ecological succession stages after wildfires. © 2013 The Linnean Society of London, Botanical Journal of the Linnean Society, 2013, 173, 594-605. [ABSTRACT FROM AUTHOR]

Compression fossils from the Silurian and Devonian of southern Britain, composed of cuticles and tubes, were described by W. H. Lang as the genus Nematothallus and placed, with Prototaxites, in Nematophytales, related neither to algae nor tracheophytes. Dispersed cuticles of Nematothallus and perforated forms assigned to Cosmochlaina were frequently recovered in macerates, their affinities being unresolved. New collections from a Lochkovian locality in the Welsh Borderland permitted the reconstruction of the stratified thalli of these nematophytes; they comprise a superficial cortex (which produced the cuticles) overlying a palisade zone composed of septate, parallel tubes, presumed to be hyphae, and a basal zone comprising wefts of randomly interwoven hyphae. Excellent three dimensional preservation allows the erection of a new species of Nematothallus, N. williamii. A similar anatomy is seen in a new group of fossils with either circular incisions in the cortex or complete separation of thickened cortical cells, presumably comprising a developmental sequence. By their stratified organization the nematophytes differ from extant and extinct algae and bryophytes and the enigmatic Spongiophyton. A complex anatomy and septate tubes suggest affinity with lichenized fungi. Limited data support a fungal rather than embryophyte chemistry, but a photobiont is missing. Nematophytes, globally widespread in cryptogamic covers from mid-Ordovician times, added to the biodiversity in early terrestrial ecosystems and enhanced chemical weathering. © 2013 The Linnean Society of London, Botanical Journal of the Linnean Society, 2013, 173, 505-534. [ABSTRACT FROM AUTHOR]

We examined the genetic diversity of two orchid species, the nectar-rewarding Platanthera chlorantha and the nectarless Cephalanthera rubra, in north-eastern Poland. We found lower differences in genetic diversity between the species than we expected. The level of genetic variation at species level was lower in C. rubra ( PPOL = 14%, A = 1.14 and HE = 0.060) than in P. chlorantha ( PPOL = 25.5%, A = 1.35 and HE = 0.078). In the majority of populations of both species a high proportion of unique genotypes was noted. The overall FST values for all populations were moderate and similar for both species ( P. chlorantha: 0.251, P < 0.001; C. rubra: 0.267, P < 0.001). No relationship was found between genetic and geographical distances in either species ( P > 0.05, Mantel test). We discuss the breeding systems, small population size and population subdivision as the most important factors affecting the genetic diversity of this species. We suggest that conservation programmes should be initiated to maintain or even increase the fitness and genetic variation of populations of both species. © 2013 The Linnean Society of London [ABSTRACT FROM AUTHOR]

Phenotypic plasticity is central to the persistence of populations and a key element in the evolution of species and ecological interactions, but its mechanistic basis is poorly understood. This article examines the hypothesis that epigenetic variation caused by changes in DNA methylation are related to phenotypic plasticity in a heterophyllous tree producing two contrasting leaf types. The relationship between mammalian browsing and the production of prickly leaves was studied in a population of Ilex aquifolium ( Aquifoliaceae). DNA methylation profiles of contiguous prickly and nonprickly leaves on heterophyllous branchlets were compared using a methylation-sensitive amplified polymorphism ( MSAP) method. Browsing and the production of prickly leaves were correlated across trees. Within heterophyllous branchlets, pairs of contiguous prickly and nonprickly leaves differed in genome-wide DNA methylation. The mean per-marker probability of methylation declined significantly from nonprickly to prickly leaves. Methylation differences between leaf types did not occur randomly across the genome, but affected predominantly certain specific markers. The results of this study, although correlative in nature, support the emerging three-way link between herbivory, phenotypic plasticity and epigenetic changes in plants, and also contribute to the crystallization of the consensus that epigenetic variation can complement genetic variation as a source of phenotypic variation in natural plant populations. © 2012 The Linnean Society of London [ABSTRACT FROM AUTHOR]

The amplified fragment length polymorphism (AFLP) technique was used to examine genetic variation among old and newly emerged individuals of Hyophorbe lagenicaulis (the Round Island bottle palm) on Round Island to assess surviving levels of diversity in the wild population and to evaluate the suitability of old cultivated stocks on Mauritius as a source of seed for reintroduction. The analysis of AFLP data for 48 individuals of H. lagenicaulis (individuals from Round Island and elsewhere), two H. verschaffeltii, two H. vaughanii, one H. amaricaulis and one H. indica yielded 81 variable and six monomorphic bands. Analysis of molecular variance (AMOVA) and Shannon's indices showed a high level of genetic variation within the wild population on Round Island and a smaller amount of genetic variation among cultivated individuals. A neighbor joining analysis resulted in an unrooted network of genetic distances in which the five Hyophorbe spp. were separated and much variation within H. lagenicaulis was recovered. The Round Island populations of H. lagenicaulis contain representatives of the genetic variation found within the species as a whole. However, a few individuals, both wild and cultivated, represent apparently rare AFLP profiles, and thus, if a more representative distribution of genotypes is wanted for the wild population, cultivated sources could be introduced to Round Island from Mauritian gardens and plantings. © 2011 The Linnean Society of London, Botanical Journal of the Linnean Society, 2011, 167, 301-310. [ABSTRACT FROM AUTHOR]

The relationships between genome size and the systematic and evolutionary patterns in vascular plants are equivocal, although a close relationship between genome size and evolutionary patterns has been previously reported. However, several studies have also revealed the dynamic nature of genome size evolution and its considerable 'ups' and 'downs'. Thus, in this study, the phylogenetic relationships among three previously revealed genome size groups and among species of the highly polyploid genus Curcuma were evaluated using AFLP. Our results suggest two main lineages within Indian Curcuma reflecting evolution of genome size. The first one includes hexaploids and higher polyploids of the previously recognized genome size group I, and the second one includes mainly hexaploids of genome size groups II and III. Within genome size group I, relationships among species seem to be influenced by reticulate evolution and higher polyploids are likely to be of allopolyploid origin. Reproductive systems in Indian Curcuma vary considerably among ploidy levels and these differences considerably affect morphological and genetic variation. In general, clonally reproducing species are expected to exhibit low genotypic diversity, but, at the same time, species of allopolyploid origin are expected to maintain higher levels of heterozygosity compared with their progenitors. We investigated intra-populational genetic variability in Curcuma spp. to evaluate whether mode of reproduction or ploidy represent the main factor influencing the degree of genetic diversity. We found that hexaploid species exhibited significantly higher genetic diversity than higher polyploids (9 x, 15 x). Our results suggest that this genetic diversity pattern is largely influenced by the mode of reproduction, as higher polyploids reproduce exclusively vegetatively, whereas hexaploids reproduce mainly sexually. © 2011 The Linnean Society of London, Botanical Journal of the Linnean Society, 2011, , 388-401. [ABSTRACT FROM AUTHOR]

Phylogenetic relationships in a Malagasy clade of Sapindaceae, encompassing Molinaea (with members also in the Mascarene Islands), Neotina, Tina and Tinopsis, were inferred by expanding a previous nuclear and plastid DNA data set for the family. The circumscription of these morphologically similar genera has remained problematic since the first family-wide treatment. To investigate this situation, representative taxa were analysed to: (1) test the monophyly of the genera; (2) investigate their phylogenetic relationships; and (3) explore alternative circumscriptions that reflect phylogeny and yield genera that are morphologically coherent and easily characterized. Phylogenetic inferences supported the monophyly of the group and its subdivision into three clades. All species of Molinaea sampled belong to a clade (Clade I) that is sister to a clade comprising Neotina, Tina and Tinopsis, within which one clade (Clade II) encompasses Tinopsis and Neotina (with the latter nested within the former) and another (Clade III) comprises all taxa of Tina. These three genera can be easily distinguished from Molinaea by having two rather than three carpels, which represents an unambiguous synapomorphy. Given the paraphyly of Tinopsis with regard to Neotina and the strong support for the monophyly of Tina, two potentially viable options are available for the generic delimitation of the taxa in this clade: (1) to recognize two genera corresponding, respectively, to Clades II and III; or (2) to place all of the taxa in a single genus encompassing both clades. Based on a review of morphological evidence the second option is favoured and consequently a broad generic concept is applied. © 2011 The Linnean Society of London, Botanical Journal of the Linnean Society, 2011, , 223-234. [ABSTRACT FROM AUTHOR]

The phylogeny of Linaceae is examined, with sampling from the 13 commonly recognized genera of the family and sequence data from the plastid genes matK and rbcL. Representatives of 24 additional families of the order Malpighiales are included in the analyses, with members of Celastrales, Fabales, Fagales, Oxalidales and Rosales used as outgroups. Linaceae and both subfamilies, the temperate Linoideae and the tropical Hugonioideae, are found to be monophyletic in likelihood- and parsimony-based analyses, although the monophyly of Hugonioideae is not well supported. Average divergence time estimates using rbcL indicate that the subfamilies diverged from each other during the Palaeocene, approximately 60 million years ago. No sister group to Linaceae is consistently identified in these analyses, and relationships among families of Malpighiales are not well resolved. In accord with previous estimates of Linoideae phylogeny, Linum is shown to be nonmonophyletic, with several segregate genera nested within it, but the relationships of the south-east Asian genera, Anisadenia, Reinwardtia and Tirpitzia, remain uncertain. In Hugonioideae, Indorouchera and Philbornea are found to be closely related to members of Hugonia section Durandea. Relationships of the neotropical genera Hebepetalum and Roucheria to the palaeotropical hugonioids are not consistently resolved. © 2010 The Linnean Society of London, Botanical Journal of the Linnean Society, 2011, , 64-83. [ABSTRACT FROM AUTHOR]

The plastid rbcL and matK genes have recently been adopted as the DNA barcoding regions for plants by the Consortium for the Barcoding of Life. However, some researchers have reported problems in successfully amplifying the matK fragment across the plant kingdom. This study focused on designing order-specific primers for monocot and eudicots. In total, 6514 matK sequences were downloaded from GenBank/EBI. The percentage sequence match of three sets of previously published barcoding primers was recorded in 39 orders. In 22 of these, at least one primer was required to be redesigned. We propose 26 new PCR primers so that the matK barcode can easily and successfully be amplified. It should also be possible to increase the amplification success rate of the previously published barcoding primers by introducing degeneracy or a deoxyinosine base to the second position from the 3′ end of the primer. This will increase primer match for monocots and eudicots to approximately 97%. Finally, we argue that DNA barcoding using multiple primers (rather than a single pair) is adequate, especially in light of the recent developments in next-generation DNA sequencing. © 2010 The Linnean Society of London, Botanical Journal of the Linnean Society, 2010, 164, 1-9. [ABSTRACT FROM AUTHOR]

Ophrys iricolor and O. mesaritica are a pair of morphologically similar, closely related sexually deceptive orchids from the eastern Mediterranean. Ophrys iricolor is known to be pollinated by Andrena morio males and the specific pollinator of Ophrys mesaritica is determined as Andrena nigroaenea. Amplified fragment length polymorphism revealed O. iricolor and O. mesaritica to be genetically intermixed on the whole, although populations of O. iricolor and O. mesaritica in geographical proximity are strongly differentiated, suggesting that specific pollinators locally differentiate these taxa. Based on the available biological data and the system of pollinator attraction operative in Ophrys, we hypothesize that O. mesaritica may have arisen from O. iricolor by pollinator shift and that this is more probable than scenarios invoking hybridization as a result of mispollination by rare, non-specific flower visitors or specifically attracted insects. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 159, 583–598. [ABSTRACT FROM AUTHOR]

Apochromic forms of the Eurasian Dactylorhiza incarnata s.l. were studied in northern Europe to reveal their genetic (allozyme) and morphological diversity and to assess their systematic significance. The study included eight localities with sympatric populations of plants with anthocyanin-pigmented and apochromic flowers. Parallel samples of the two morphs were taken from each locality. Genetic variation was only found at the allozyme loci pgd, pgi and ugpp. Statistically significant differences in allele frequencies between the two colour morphs were found in two localities and demonstrate that the occurrence of apochromic individuals in D. incarnata s.l. is not always because of spontaneous mutation. At least in some localities the apochromic plants form distinct breeding groups (but local populations of different colour morphs may also be composed of several more or less distinct breeding groups). Based on molecular and morphometric data, it is proposed that the apochromic study populations from calcareous fens should be referred to D. incarnata var. ochroleuca, whereas the apochromic study populations from non-calcareous fens are better treated as aberrant local populations of var. incarnata s.l. Possible evolutionary patterns and processes are discussed and guidelines for identification of var. ochroleuca from morphological features are given. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 159, 396–407. [ABSTRACT FROM AUTHOR]

Genetic variation was investigated using AFLP markers in 12 populations of Anthurium sinuatum and A. pentaphyllum var. pentaphyllum (Araceae) in north-east Brazil, Amazonia and the Brazilian Atlantic forest. Two unique genetic patterns characterized the populations of A. sinuatum as a group, but no correlation between genetic and geographical interpopulation distance was found; the Amazonian population was not separated from that in Ceará. The isolated Ceará brejo populations of A. sinuatum were genetically distinct, but genetic diversity levels were similar to populations elsewhere, with no evidence of genetic erosion. Anthurium pentaphyllum populations were significantly different from each other; Bayesian genetic structural analysis found no common genetic pattern, but revealed genetic clusters unique to subgroups and individual populations in the Atlantic forest and French Guiana. Anthurium pentaphyllum and A. sinuatum can be distinguished genetically, but individuals of both species formed intermediate genetic clusters that blurred their distinction. We suggest that genetic mixing of A. sinuatum and A. pentaphyllum has occurred in north-east Brazil, possibly connected with cycles of humid forest expansion. The weak genetic structure in A. sinuatum is consistent with the natural fragmentation of continuous forest areas, possibly during the Holocene. This study highlights the scientific importance of the highly threatened brejo forests for tropical American biogeography. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 159, 88–105. [ABSTRACT FROM AUTHOR]

A morphologically interesting hyphomycete was collected from submerged wood in a stream in Doi Suthep-Pui National Park, Thailand. It is described as Aquaticheirospora lignicola gen. and sp. nov., and is characterized by euseptate conidia with divergent arms, which are vertically inserted in different planes to a basal cell. The genus differs from other chirosporous genera in having synnematous conidioma and conidia that are produced on conidiogenous cells borne at the apices of synnemata. The morphological characterization of this new fungus is reported and compared with similar chirosporous genera. To investigate the teleomorphic and phylogenetic relationships of this new taxon, three different regions of the ribosomal gene [18S rDNA, 28S rDNA, and internal transcribed spacer (ITS) including 5.8S] were sequenced and analysed. The results of phylogenetic analyses based on 18S, 28S, and partial ITS including 5.8S rDNA, employing different tree-making methods, indicate that Aquaticheirospora lignicola is closely related to the ascomycetes family Massarinaceae (Order: Pleosporales). The Massarinaceae as currently circumscribed is monophyletic. Massarina australiensis and M. bipolaris, however, appear to belong to the Lophiostomataceae. © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society, 2007, 155, 283–296. [ABSTRACT FROM AUTHOR]

Allozyme electrophoresis was conducted to survey the levels and distribution of genetic diversity in the tetraploid perennial larkspur Delphinium montanum (Ranunculaceae), which is endemic to the eastern Pyrenees of Spain and France and considered to be endangered. Seven populations were sampled, resolving 14 putative enzymatic loci belonging to eight enzymes. Banding patterns stained in gels revealed several enzymatic duplications attributable to autotetraploidy, such as the presence of both balanced and unbalanced heterozygotes and the lack of fixed heterozygosity. However, variability in D. montanum ( P = 23.8%, A = 1.48, and He = 0.082) was lower than that expected for an autotetraploid species. This, in addition to the scarcity of loci showing three or four different alleles, could indicate that this species has suffered genetic erosion through population bottlenecks, or, alternatively, that it is undergoing diploidization. © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society, 2007, 155, 211–222. [ABSTRACT FROM AUTHOR]

Until recently, Sellocharis paradoxa Taubert, the only species of this Genisteae genus, was known solely by the isotypes. Recent new collections in Rio Grande do Sul, southern Brazil, have enabled data on chromosome number and karyotype morphology to be obtained for the first time. S. paradoxa has 2 n = 20 chromosomes, and a bimodal asymmetrical karyotype, composed of one pair of long ( c. 6.3 µm) metacentric, five pairs of shorter acrocentric, and four pairs of shorter telocentric chromosomes ranging from c. 3.7 to 2.7 µm. The chromosome number and karyotype morphology of S. paradoxa do not fit into the Genisteae pattern. Existing information is so far insufficient to answer evolutionary questions about its origin and phylogenetic relationships, but the uniqueness of this taxon, first indicated by its peculiar leaf arrangement, and now supported by its uncommon karyological constitution, strongly suggests that the suprageneric taxonomic position of S. paradoxa should be re-evaluated. © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society, 2007, 155, 223–226. [ABSTRACT FROM AUTHOR]

Levels of allozyme variation, population genetic structure, and fine-scale genetic structure (FSGS) of the rare, both sexually and clonally reproducing terrestrial orchid Epipactis thunbergii were examined for eight ( N = 734) populations in a 20 × 20-km area in South Korea. Twenty-three putative allozyme loci resolved from 15 enzyme systems were used. Extremely low levels of allozyme variation were found within populations: the mean frequency of polymorphic loci was 3.8% [isocitrate dehydrogenase ( Idh-2) with two alleles was polymorphic across populations], the mean number of alleles per locus was 1.04, and the mean expected heterozygosity was 0.013. The overall fixation index was not significantly different from zero ( FIS = 0.069), although the species is self-compatible. However, a significantly high degree of population differentiation was found between populations at Idh-2 ( FST = 0.388) in the studied area. Furthermore, spatial autocorrelation analyses revealed a significant FSGS (up to 3 m) within populations. These observations suggest that the main explanatory factors for the extremely low levels of genetic diversity and the shaping of the population genetic structure of E. thunbergii are genetic drift as a result of a small effective population size, a restricted gene flow, and the isolation of populations. Considering the current genetic structure of E. thunbergii, three guidelines are suggested for the development of conservation strategies for the species in South Korea: (1) protection of habitats of standing populations; (2) prohibition by law of any collection of E. thunbergii; and (3) protection of nearby pollinator populations, given the fact that fruit set in natural habitats is very low. © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society, 2007, 155, 161–169. [ABSTRACT FROM AUTHOR]

Karyological studies were carried out on ten populations comprising six species of Soroseris in the tribe Lactuceae (Asteraceae), all endemic to the alpine Sino-Himalayan region and poorly known cytogenetically. The single species of Stebbinsia (one population) and two species of Syncalathium (three populations) were also examined for the first time. The basic chromosome number for the three genera is x = 8. Stebbinsia and most species of Soroseris are diploids with 2 n = 2 x = 16 = 14m + 2sm and have a karyotype asymmetry type 1A. Three species of Soroseris are tetraploid (2 n = 4 x = 32 = 28m + 4sm). A karyotype of 2 n = 2 x = 16 = 14m(2SAT) + 2sm with type 1A asymmetry was found in Syncalathium kawaguchii, and of 2 n = 2 x = 16 = 6m + 10sm with type 2A asymmetry for two populations of Syncalathium souliei. The relationships between Soroseris and the other two genera are discussed. Our cytological results suggest that polyploidy plays a minor role in the chromosome evolution of plants from the Himalayan mountains and adjacent regions. © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society, 2007, 154, 79–87. [ABSTRACT FROM AUTHOR]

Chromosome counts are reported in 29 populations representing 20 species and one subspecies of the genera Callicephalus (one sp.), Klasea (seven spp.), Myopordon (two spp.), Oligochaeta (one sp.), and Rhaponticum (nine spp., one ssp.). Eleven reports are new, the others supplement limited previous data. New and published cytological data are summarized and evaluated critically in light of current taxonomic treatments and evolutionary hypotheses. Basic chromosome numbers are a valuable source of taxonomic information and relate well to the phylogeny. They are quite conserved in Klasea (only x = 15), the sister group of the remaining genera, and in the early branching genera of the Rhaponticum group ( x = 14 for Centaurothamnus and Callicephalus). However, a more complex pattern of genome evolution is present among the more derived clades, Oligochaeta plus Myopordon ( x = 12, 14) and the genus Rhaponticum ( x = 12, 13). The occurrence of x = 12 in Oligochaeta divaricata and Rhaponticum carthamoides seems to be the result of a recent event of chromosome fusion, as suggested by the fragility of particularly long pairs of chromosomes. The use of chromomycin staining, including an enzymatic digestion step that facilitates spreading and permits a reduction of potential fragmentation, only partially resolves this problem. © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society, 2007, 153, 193–201. [ABSTRACT FROM AUTHOR]

The main aspects of seed ontogeny in Senna corymbosa were studied by standard anatomical microtechniques for light microscope observations. The results revealed an ana-campylotropous, bitegmic, and crassinucelate mature ovule. A single archesporocyte developed by an archesporial cell enlargement from the subhypodermal multicellular archesporium. Meiosis originated linear or T-shaped megasporic tetrads. The functional megaspore was the chalazal one. Megagametophytic development conformed to the Polygonum type. Fertilization was porogamic. Endosperm development was free nuclear and conformed to a chalazal haustorium. Cellular endosperm was initiated from the micropylar end during the globular embryo stage. Embryogeny derived from a linear proembryonal tetrad. The mature embryo showed an oblique axis. The testa derived from the outer ovular integument. Nucellar and endosperm remnants, and the micropylar region of the inner ovular integument, persisted at embryo maturity. The absence of a pleurogram would be adaptative to wetland habitats. The taxonomic use of the mature embryo axis in the Cassieae and the phylogenetic employment of megasporic arrangements in Leguminosae needs some reinterpretation. © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society, 2007, 153, 169–179. [ABSTRACT FROM AUTHOR]

Interspecific and intergeneric hybridizations were carried out in an investigation of genome homology between Hystrix patula and other species of Hystrix, as well as the generic relationships between H. patula and its related species. Meiotic pairing in the hybrids H. patula × H. duthiei ssp. longearistata (Ns–), H. patula × Pseudoroegneria spicata (St), H. patula × Pse. libanotica (St), Elymus sibiricus (StH) × H. patula, H. patula × E. wawawaiensis (StH), Roegneria ciliaris (StY) × H. patula, H. patula × R. grandis (StY), and H. patula × Psathyrostachys huashanica (Nsh) averaged 1.32, 6.53, 5.62, 10.08, 12.83, 3.57, 3.98, and 0.29 bivalents per cell, respectively. The results indicate that: (1) H. patula has no genome homology with H. duthiei ssp. longearistata or the Ns genome from Psathyrostachys; (2) H. patula contains the same StH genomes as the Elymus species, and the St genome is homologous to the genome of Pse. spicata and Pse. libanotica; and (3) H. patula has a low genome affinity with the StY genomes of Roegneria. Therefore, it is reasonable to treat H. patula Moench as E. hystrix L. © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society, 2007, 153, 213–219. [ABSTRACT FROM AUTHOR]

Mitotic or meiotic chromosome numbers for 42 accessions belonging to 39 species of different genera of Asteraceae were determined. First chromosome counts are reported for one genus ( Gymnocoronis), 14 species, and one variety. These are as follows: Solidago chilensis var. megapotamica (2 n = 2 x = 18), Chromolaena barbacensis (2 n = 3 x = 30), Chromolaena christieana (2 n = 3 x = 30), Chromolaena hirsuta (2 n = 4 x = 40), Chromolaena verbenacea ( n = 20 II, 2 n = 4 x = 40), Disynaphia multicrenulata (2 n = 2 x = 20), Gymnocoronis spilanthoides var. subcordata (2 n = 2 x = 20), Mikania thapsoides (2 n = 4 x = 68), Stevia commixta (2 n = 2 x = 22), Porophyllum brevifolium (2 n = 4 x = 44), Viguiera rojasii (2 n = 2 x = 34), Pterocaulon angustifolium (2 n = 2 x = 20), Gochnatia haumaniana (2 n = 4 x = 44), Senecio ostenii (2 n = 4 x = 40), Senecio pinnatus (2 n = 8 x = 80), and Lepidaploa amambaia (2 n = 2 x = 28). Chromosome numbers differing from those reported previously in the literature were found in Campuloclinium macrocephalum (2 n = 2 x = 20), Melanthera latifolia (2 n = 4 x = 60), Chrysolaena flexuosa (2 n = 2 x = 20), and Cyrtocymura cincta (2 n = 4 x = 40). The relevance of the results is discussed in relation to the available data for each of the analysed taxa. © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society, 2007, 153, 221–230. [ABSTRACT FROM AUTHOR]

Four different cytotypes have been reported for Senecio jacobaea L. ssp. jacobaea throughout Europe, with the most common occurrence of tetraploids (2 n = 40). Here we present a survey of previously published chromosome number data on this subspecies and its geographical distribution, and focus on populations from Pannonia and the Carpathians. Two ploidy levels have been determined in the study area, using chromosome counting and flow cytometry: tetraploid (2 n = 40) and octoploid (2 n = 80). Fifty-one populations originating from Slovakia, Austria, the Czech Republic, Hungary, Ukraine and Romania have been analysed. Multivariate morphometric analyses have been performed on 39 populations to study morphological differentiation between these two cytotypes. Despite slight morphological tendencies expressed on the level of populations, tetraploid and octoploids cannot be reliably distinguished morphologically and they are not taxonomically classified formally here. © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society, 2007, 153, 231–242. [ABSTRACT FROM AUTHOR]

Levels of allozyme variation and intrapopulation spatial genetic structure of the two terrestrial clonal orchids Liparis kumokiri, a self-compatible relatively common species, and L. makinoana, a self-incompatible rare species, were examined for 17 ( N = 1875) and four ( N = 425) populations, respectively, in South Korea. Populations of L. makinoana harboured high levels of genetic variation ( He = 0.319) across 15 loci. In contrast, L. kumokiri exhibited a complete lack of allozyme variation ( He = 0.000). Considering the lack of genetic variability, it is suggested that current populations of L. kumokiri in South Korea originated from a genetically depauperate ancestral population. For L. makinoana, a significant deficit of heterozygosity (mean FIS = 0.198) was found in population samples excluding clonal ramets, suggesting that pollen dispersal is localized, generating biparental inbreeding. The significant fine-scale genetic structuring (≤ 2 m) found in a previous study, in addition to the moderate levels of population differentiation ( FST = 0.107) and the significant relationship between genetic and geographical distances ( r = 0.680) found here, suggests a leptokurtic distribution of seed dispersal for L. makinoana. Although populations of L. makinoana harbour high levels of genetic variation, they are affected by a recent genetic bottleneck. This information suggests that genetic drift and limited gene flow could be the main evolutionary forces for speciation of a species-rich genus such as Liparis. © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society, 2007, 153, 41–48. [ABSTRACT FROM AUTHOR]

The patterns of genetic variability of seven Bulbophyllum Thouars species were investigated using 14 enzymatic loci, and compared with those of other Neotropical myophilous orchid species. The genetic variability estimated was very high ( He = 0.39–0.61, P = 86–100%, A = 2.6–3.8), despite the small population sizes, which may be explained by the vegetative reproduction. Of the three species with multiple populations, only B. epiphytum showed moderate values of genetic structuring. Environmental characteristics and seed dispersal mechanisms are important in understanding the differences in the population structure observed. Almost all pairs of species showed low genetic similarity, indicating a long period of divergence. Our results suggest that B. adiamantinum and B. insectiferum, species currently classified in different sections of the genus, are more closely related than previously thought. © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society, 2007, 153, 33–40. [ABSTRACT FROM AUTHOR]

Tournefortia rufo-sericea is an endemic member of the Galápagos angiosperm flora. Although not uncommon within the archipelago, its status is presently listed as vulnerable and, as such, a complete knowledge of its pollination biology may prove useful in preventing its decline. Pollination experiments, flower-visitor observations, nectar and fluorescence studies, as well as pollen : ovule ratio and pollen size studies were included in this investigation. The small, white flowers of this species set fruit via open pollination (81%), autonomous self-pollination (80%), diurnal pollination (80%), and nocturnal pollination (85%). Ants are the most common visitor to the flowers of this species, primarily during the day, whereas beetles and moths make visits at night. A small amount of nectar is presumably produced, as moths are often seen probing the corollas. Experiments with fluorescent dust did not support interflower pollen movement. The pollen : ovule ratio was 4972 : 1, which suggests xenogamy, and the mean pollen size was 21 µm. Despite the pollen : ovule ratio, it appears that this species exhibits a breeding strategy of facultative autogamy, in which the majority of flowers set fruit via autonomous self-pollination, but limited outcrossing may occur when pollinators are available. Conservation efforts for T. rufo-sericea should focus on the control or eradication of exotic species. © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society, 2007, 153, 21–31. [ABSTRACT FROM AUTHOR]

Chromosomes of four species in three genera of Commelinaceae from China were examined. Spatholirion longifolium had 2 n = 20. This small genus is considered to be of a possible polyploid origin based on x = 5, a basic number shared by its closest ally, the monospecific genus Streptolirion, with its only species having 2 n = 10. The two genera were found to be very different from each other in their karyotypic constitution. The differences in both chromosome number (2 n = 20 vs. 10) and karyotypic constitution support their separation as two independent genera. The remaining three species, Amischotolype hispida, Porandra ramosa and P. scandens, all had 2 n = 36. In view of the occasional occurrence of 2 n = 18 in the African Coleotrype, a genus very close to Amischotolype and Porandra in gross morphology, these three species are all very probably polyploid based on x = 9. The high degree of karyotypic similarity of the three genera also strongly indicates their close affinity and supports their placement in the subtribe Coleotrypinae. © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society, 2006, 152, 399–403. [ABSTRACT FROM AUTHOR]

The chromosome number and morphology of eight species belonging to the section Santolinoideae of the genus Achillea L. (Asteraceae) were investigated using karyological techniques. The species studied were Achillea cucullata (Hausskn.) Bornm., A. vermicularis Trin., A. monocephala Boiss. & Bal., A. boissieri (Hausskn.) Bornm., A. santolina L., A. gypsicola Hub.-Mor., A. goniocephala Boiss. & Bal., and A. spinulifolia Fenzl ex Boiss. In these species, the chromosome numbers were 2 n = 18 in A. vermicularis, A. monocephala, and A. boissieri, 2 n = 18A + 1B in A. spinulifolia, 2 n = 36 in A. cucullata and A. santolina, and 2 n = 54 in A. gypsicola and A. goniocephala. All of the chromosomes had median point (M), median region (m), or submedian (sm) centromeres. An increase in asymmetry was not observed in the karyotypes of the species. © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society, 2006, 151, 573–580. [ABSTRACT FROM AUTHOR]

Published phylogeny reconstructions of the palm family (Arecaceae) are based on plastid DNA sequences or restriction fragment length polymorphisms (RFLPs), nuclear DNA sequences, morphological characters or a combination thereof, and include between 33 and 90 palm species. The present study represents all previously recognized subfamilies, tribes and subtribes of palms and 161 of the 189 genera. The plastid DNA region matK was sequenced for 178 palm species and ten commelinid monocot outgroup species, and was combined with new and previously published plastid DNA sequences of trnL– trnF, rps16 intron and rbcL. The addition of matK sequences and more taxa resulted in a highly resolved and largely well-supported phylogeny. Most importantly, critical basal nodes are now fully resolved and, in most cases, strongly supported. On the basis of this phylogeny, we have established a new subfamilial classification of the palms, in which five subfamilies are recognized, rather than the six that were included in the previous classification. The circumscriptions of the subfamilies Calamoideae and Nypoideae were corroborated. The phylogeny supported a new circumscription for the subfamily Coryphoideae, including all taxa previously recognized in Coryphoideae with the addition of the tribe Caryoteae, formerly of the subfamily Arecoideae. The phylogenetic analysis also supported a new delimitation for the subfamily Ceroxyloideae that contains the tribes Cyclospatheae and Ceroxyleae, and all genera formerly included in the subfamily Phytelephantoideae, but excludes the tribe Hyophorbeae. Finally, the subfamily Arecoideae was modified to exclude the tribe Caryoteae and to include the tribe Hyophorbeae. © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society, 2006, 151, 15–38. [ABSTRACT FROM AUTHOR]