Geographical variation and environmental correlates of functional trait distributions in palms (Arecaceae) across the New World

Functional traits play a key role in driving biodiversity effects on ecosystem functioning. Here, we examine the geographical distributions of three key functional traits in New World palms (Arecaceae), an ecologically important plant group, and their relationships with current climate, soil and glacial–interglacial climate change. We combined range maps for the New World (N = 541 palm species) with data on traits (leaf size, stem height and fruit size), representing the leaf–height–seed plant strategy scheme of Westoby, to estimate median trait values for palm species assemblages in 110 × 110‐km grid cells. Spatial and non‐spatial multi‐predictor regressions were used with the Akaike Information Criterion to identify minimum adequate models. Present‐day seasonality in temperature and precipitation played a major role in explaining geographical variation of all traits. Mean annual temperature and annual precipitation were additionally important for median leaf size. Glacial–interglacial temperature change was the most important predictor for median fruit size. Large‐scale soil gradients played only a minor role overall. These results suggest that current climate (larger median trait values with increasing seasonality) and glacial–interglacial temperature change (larger median fruit size with increasing Quaternary temperature anomaly) are important drivers for functional trait distributions of New World palms. © 2015 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 179 , 602–617.     

Application of plastid and nuclear markers to DNA barcoding of Euro‐Mediterranean oaks (Quercus,Fagaceae): problems,prospects and phylogenetic implications

DNA barcoding, a species identification system based on sequences from a short, standardized DNA region, has emerged recently as a new tool for taxonomists. We investigated the discriminatory power of a subset of highly variable proposed plant barcoding loci (matK, trnH‐psbA, ITS2) in Quercus, a taxonomically complex tree genus of global importance. The research included all currently recognized species and some major variants of the Mediterranean region and Europe (32 taxa) and 17 East Asian and North American species used for comparison. Based on sequence character state, we assigned unique plastid haplotypes to 40.8% of the investigated species; ITS2 increased the resolution up to 87.8% of total taxa. Nevertheless, unsuccessful genetic distance‐based discrimination questioned the potential efficiency of correct species identification for future studies. Most species appeared to be nonmonophyletic in parallel phylogenetic tests. Three subgeneric groups were outlined, with different rates of within‐group variability and geographical differentiation. Members of one of these groups (corresponding to the Eurasian Group Ilex) were paraphyletic to Group Quercus from the New and Old World and the Eurasian Group Cerris. The data gathered indicate that barcoding markers may help to identify closely related species clusters and contribute to the inference of major diversification and evolutionary patterns in oaks, but the methodology per se appears to be of limited efficacy in defining species limits, unless we make a profound revision of traditional Quercus taxonomic categories. © 2013 The Linnean Society of London, Botanical Journal of the Linnean Society, 2013, 172 , 478–499.     

Floral scents in butterfly-pollinated plants: possible convergence in chemical composition

The study explores whether or not there are convergent patterns in floral scent composition among plant species that completely or partially rely on butterflies for pollination. Floral scent compounds were analysed from 22 flowering butterfly-pollinated plant species, representing 13 families which originate mainly from temperate North Europe but also from tropical and temperate America. Scents were collected using the dynamic headspace adsorption method and identified with coupled gas chromatography and mass spectrometry (GC-MS). In total, 217 floral scent compounds were identified, with the number per species ranging from 8 to 65. The major emerging pattern is the occurrence of certain compounds emitted exclusively by the flowers of many of the investigated species in major amounts – the benzenoids phenylacetaldehyde and 2-phenylethanol, the monoterpenes linalool and linalool oxide (furanoid) I and II and the irregular terpene oxoisophorone. It is likely that these compounds serve as a signal to attract pollinating butterflies, and may have evolved in conjunction with the sensory capabilities of butterflies as a specific group of pollinators. While there is convergence in terms of the compounds sharing this function there has been a geographical divergence in terms of their relative abundance. The predominance (in terms of both numbers and relative amount) of benzenoids in many of the scent blends of the European temperate species and of linalool and its derivatives in those of the American species constitute two discernible groups among these plants.  © 2002. The Linnean Society of London, Botanical Journal of the Linnean Society , 2002, 140 , 129–153.     

The iterative process of plant species inventorying for obtaining reliable biodiversity patterns

We require representative data of species occurrence to explain plant diversity patterns, but most of the available information is incomplete and biased. To improve our knowledge, we suggest that species inventorying should be an iterative process encompassing the following: (1) the detection of taxonomic and geographical gaps; (2) the planning of a survey design to reduce such gaps; and (3) the evaluation of field sampling results. Here, we focus on the latter phase for the bryophytes of Terceira Island (Azores) for which we have previously estimated < 1% of the area as well surveyed based on historical collections. To examine the performance of our stratified survey based on two factors (land use and environmental regions), we used rarefaction curves, ANOVA tests and bootstrap sampling. We recorded 40% of all the species known for the island and presented eight new citations. The species assemblages remained similar between historical and current inventories. Most localities had completeness values > 85%, but we always exceeded the optimal sampling effort. Land uses and environmental regions affected species diversity, but, unexpectedly, to a different degree. Our study illustrates the difficulties of planning field surveys to obtain reliable biodiversity patterns, even when prior information and standardized sampling protocols are explicitly considered. © 2015 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 177 , 491–503.     

Historical legacies in the geographical diversity patterns of New World palm (Arecaceae) subfamilies

The extent to which species richness patterns of the major palm subfamilies in the Americas are controlled by lineage history was studied. Based on the fossil record, we suggest that the subfamily Coryphoideae has followed a boreotropical dispersal route into Central and South America, whereas Calamoideae (tribe Lepidocaryeae), Ceroxyloideae and Arecoideae have Gondwana/South America-biased histories. However, Arecoideae has been present and diverse in both South and Central America at least since the early Tertiary. We used regression analyses to evaluate the relative importance of environmental factors and spatial variables (as substitutes for historical or other non-environmental factors) as determinants of geographical variation in species richness for each subfamily. Given the different lineage histories, we hypothesized that: (1) coryphoid richness should be least strongly controlled by the modern environment and exhibit a strong non-environmental bias towards Central and North America, reflecting its boreotropical invasion route, (2) calamoid species richness should exhibit a non-environmental bias towards South America, reflecting its long African–South American history, and (3) arecoid species richness should be most strongly environmentally determined, reflecting the long arecoid residency in both Central and South America. The regression analyses confirmed the hypothesized effects of lineage history on the geographical patterns in species richness. Hence, modern species richness patterns in the New World palm subfamilies strongly reflect their divergent biogeographical histories.  © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 151 , 113–125.     

Phylogenetics,character evolution,and distribution patterns of the greenbriers,Smilacaceae (Liliales), a near‐cosmopolitan family of monocots

Smilacaceae, composed of Smilax and Heterosmilax, are a cosmopolitan family of > 200 species of mostly climbing monocots with alternate leaves characterized by reticulate venation, a pair of petiolar tendrils and usually prickly stems. Although there has been a long history of studying Smilax since Linnaeus named the genus in 1753, the phylogenetic history of this dioecious family remains unclear. Here we present results based on nuclear ribosomal internal transcribed spacer (nrITS) and plastid matK and rpl16 intron DNA sequence data from 125 taxa of Smilacaceae. Our taxon sampling covers all sections of Smilax and Heterosmilax and major distribution zones of the family; species from Ripogonaceae and Philesiaceae are used as outgroups. Our molecular analysis indicates that phylogenetic relationships largely contradict the traditional morphological classification of the family, instead showing a conspicuous geographical pattern among the species clades. The previously recognized genus Heterosmilax was found to be embedded in Smilax. Species in the family are separated into primarily New World and Old World clades, except for a single species lineage, Smilax aspera, that is sister to the remaining species of the family, but with poor statistical support. Ancestral character state reconstructions and examination of distribution patterns among the clades provide important information for future taxonomic revisions and historical biogeography of the group. © 2013 The Linnean Society of London, Botanical Journal of the Linnean Society, 2013, 173 , 535–548.     

Phenolic chemotaxonomy and phytogeography of Adiantum

The occurrence of flavonoid glycosides and hydroxycinnamic acid esters has been examined in the fronds of 58 species of Adiantum , covering the morphological and geographical range of the genus. The genus may be divided into five sections on the basis of their flavonoid patterns. The correspondence of these patterns with the major existing systems of classification is discussed. The A. capillus-veneris group is the least homogeneous, both morphologically and chemically, and requires further study. However, the flavonoid patterns of extracts of the fronds of thirteen samples of the cosmopolitan species A. capillus-veneris from different geographical areas were found to be qualitatively similar, suggesting this species has probably spread relatively recently. Adiantum species which are restricted to the Old World have a basically different flavonoid pattern from those species which are exclusive to the New World. The phytogeographical and phylogenetic implications of these results are outlined and it is concluded that the Old World species represent more ancient stocks than those in the New World.     

A new species of Linum (Linaceae) from west Anatolia, Turkey

A new species, Linum vuralianum Yılmaz & Kaynak, is described and illustrated from west Anatolia, Turkey. It is closest to L. flavum L., but differs by its annual or biennial life form, the presence of rosette leaves at anthesis, and the absence of staminodes. The World Conservation Union (IUCN) threat category and observations on the population are noted. The geographical distribution of the new species and its related taxon is given.  © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society , 2008, 156 , 459–462.     

A phylogeny of Thermopsideae (Leguminosae: Papilionoideae) inferred from nuclear ribosomal internal transcribed spacer (ITS) sequences

Based on nuclear ribosomal DNA internal transcribed spacer (ITS) sequences, Thermopsideae is phylogenetically studied within a genistoid background. Analysis reveals that the tribe is not supported as a monophyletic group. Some species of Sophora s.s are nested within it. The central Asian desert Ammopiptanthus forms an isolated clade but is relatively remote to other Thermopsideae members. Piptanthus , Anagyris , Baptisia , and Thermopsis are clustered together into a robust clade. We hence propose that the tribe could either be reduced to just the four 'core genera' with Ammopiptanthus excluded, or, as an alternative, that Thermopsideae could become part of a new Sophoreae s.s. if it is re-circumscribed in the future. Both Piptanthus and Baptisia appear as monophyletic. The genus Anagyris is closer to some east Asian Thermopsis species than to Piptanthus . The east Asian and North American disjunct Thermopsis is not monophyletic. The ITS results suggest a geographical division between the Old World and New World Thermopsis . The east Asian species are clustered with Piptanthus and Anagyris , whereas the North American species are allied to Baptisia . Nonetheless, the only two north-eastern east Asian native Thermopsis species appear to be more related to the North American group than to the east Asian one. The related biogeographical significance has therefore been additionally discussed.  © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 151 , 365–373.     

Phylogenetics and taxonomy of the New World leafy spurges,Euphorbia section Tithymalus (Euphorbiaceae)

The 480 species of leafy spurges, Euphorbia subgenus Esula, represent the main temperate radiation in the large genus Euphorbia. This group is distributed primarily in temperate Eurasia, but with smaller, disjunct centres of diversity in the mountains of the Old World tropics, in temperate southern Africa and in the New World. The majority of New World diversity (32 species) occurs in a single section, section Tithymalus. We analysed sequences of the nrITS and plastid ndhF, trnH‐psbA, trnS‐trnG and trnD‐trnT regions to reconstruct the phylogeny of section Tithymalus and to examine the origins and diversification of the species native to the New World. Our results indicate that the New World species of section Tithymalus form a clade that is sister to the widespread, weedy E. peplus. The New World species fall into two primary groups: a ‘northern annual clade’ from eastern North America and a diverse clade of both annual and perennial species that is divided into three subgroups. Within the second group, there is a small ‘southern annual clade’ from Texas and northern Mexico, a perennial ‘Brachycera clade’ from the western United States and northern Mexico, and a perennial ‘Esuliformis clade’ from montane areas of Mexico, Guatemala, Honduras and the Caribbean island of Hispaniola. Ancestral state reconstructions indicate that the annual habit probably evolved in the ancestor of E. peplus and the New World clade, with a subsequent reversal to the perennial habit. In conjunction with this phylogenetic framework, the New World species of section Tithymalus are comprehensively reviewed. © 2014 The Linnean Society of London, Botanical Journal of the Linnean Society, 2014, 175 , 191–228.     

A new species of Goniothalamus (Annonaceae) from New Caledonia, representing a significant range extension for the genus

A previously unknown Annonaceae species from the South Pacific island of New Caledonia is described as Goniothalamus dumontetii . This is the first Goniothalamus species reported from the island, and the easternmost record for the genus. It is easily distinguished from its congeners by the shape of the monocarp (flattened elongate with lateral triangular projections), which reflects the shape of the seeds (flattened rhombohedral). The conservation status of the species is evaluated as endangered (EN) using World Conservation Union (IUCN) red list categories, as it is known from only one relatively small population. The interpretation of geological and molecular data suggests that Goniothalamus dispersed to New Caledonia relatively recently, and does not represent a relict of the break-up of Gondwana.  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 155 , 497–503.     

Molecular phylogenetics of Kosteletzkya (Malvaceae,Hibisceae) reveals multiple independent and successive polyploid speciation events

Kosteletzkya s.s. is a genus of 17 species (excluding the endemic species of Madagascar), found in the New World, continental Africa, Madagascar, and Southeast Asia. Recent chromosome counts revealed diploid, tetraploid, and hexaploid species. To estimate the history of the genus, we sequenced nuclear and plastid loci for nearly all Kosteletzkya spp., in the majority of cases, with multiple accessions per species. The African species form a paraphyletic grade relative to a New World clade. Polyploidy has occurred only in some African species, resulting in the relatively ancient formation of one putative autotetraploid species (K. semota), one recent allotetraploid species (K. borkouana), two relatively ancient allotetraploid species (K. begoniifolia and K. rotundalata) and one recent allohexaploid species (K. racemosa). Our inferences regarding the hypothesized parentage of the polyploids mostly corroborate previous work based on chromosome‐pairing patterns in artificial hybrids, highlighting the utility of these complementary data sources. © 2015 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 179 , 421–435.     

Phylogenetics of Escallonia (Escalloniaceae) based on plastid DNA sequence data

Escallonia (Escalloniaceae) is a New World genus of c. 39 species distributed mainly in the South American highlands. Plastid DNA sequence data from the intergenic spacers trnS‐trnG and 3′ trnV‐ndhC and the ndhF gene for 32 species were used to examine the relationships among species and related genera and to analyse the relationship between phylogeny and the geographical distribution of the species. Maximum parsimony and Bayesian inference were employed to analyse the data. The sister relationship of Escallonia to Forgesia and Valdivia was corroborated. We recovered five strongly supported clades that are geographically structured, suggesting that the evolutionary history of the genus may be linked to historical processes, including the uplift of mountainous systems in South America. © 2013 The Linnean Society of London, Botanical Journal of the Linnean Society, 2013, 173 , 442–451.     

Multivariate morphometric analysis of the Potamogeton compressus group (Potamogetonaceae)

The Potamogeton compressus group is a complex of three to five closely related species with a circumpolar distribution in the Northern Hemisphere. Multivariate morphometric analyses (principal component analysis, cluster analysis, canonical and classificatory discriminant analyses) were used to elucidate the patterns of variation within this group and to test the morphological differentiation of the species recognized in the current literature. From the entire distribution range, 156 specimens of the group were included in the numerical methods. Results from morphological comparison are discussed in relation to molecular data, reproductive behaviour and geographical distribution. Morphometric analyses provided evidence that this complex can be clearly divided into three groups, one of which was subdivided mainly on the basis of allopatric occurrence and genetic differentiation. These groups correspond to four species accepted here: P. acutifolius (temperate regions of Europe), P. compressus (boreal and temperate regions of Europe and Asia), P. manchuriensis (northeastern China and Russian Far East) and P. zosteriformis (boreal and temperate regions of North America). Two species, P. acutifolius and P. compressus, are partly sympatric, but clearly differentiated morphologically and genetically, and effectively isolated reproductively. Endemic P. manchuriensis is characterized by a unique combination of characters and an occurrence in a limited geographical area. Allopatric P. zosteriformis is weakly differentiated morphologically from P. compressus, but differs markedly in molecular markers correlated with geographical differentiation. It may represent a cryptic species. In contrast, a recently suggested concept of southern Siberian P. henningii was not supported by our analyses. Plants so named are considered here as slender phenotypes of the widespread and variable P. compressus. © 2012 The Linnean Society of London, Botanical Journal of the Linnean Society, 2012, 170 , 112–130.     

Systematics and biogeography of the New World species of Trichadenotecnum Enderlein (Insecta: Psocodea: 'Psocoptera': Psocidae)

The taxonomy of the New World species of the genus Trichadenotecnum is revised. A total of 44 species, including 29 new species, were treated. These species are classified into 12 monophyletic species groups, eight of them newly proposed here. Two species previously assigned to Trichadenotecnum , T. pichincha New & Thornton and T. sylvaticum Turner, are recognized as not belonging to this genus. Phylogenetic relationships among 16 previously and presently proposed species groups are estimated based on a data matrix of 58 morphological characters. Trees from these analyses support monophyly of Trichadenotecnum and the proposed species groups. The New World species were divided into three major clades. Based on the phylogenetic hypothesis and distributional pattern of the species groups, the biogeographical history of the New World Trichadenotecnum is discussed.  © 2008 The Linnean Society of London, Zoological Journal of the Linnean Society , 2008, 153 , 651–723.     

Nomenclatural changes in preparation for a World Rubiaceae Checklist

During the preparation of a World Rubiaceae Checklist , numerous unplaced taxa were encountered, including illegitimate and invalid names, and species for which generic placement is uncertain. In this contribution, 35 new combinations and 20 new names are proposed, and the names of three taxa are validated.  © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society , 2008, 157 , 115–124.     

Clinal variability of oil and nectar rewards in Monttea aphylla (Plantaginaceae): relationships with pollinators and climatic factors in the Monte Desert

Monttea aphylla flowers simultaneously produce oil and nectar, rewards known to differentially attract ecologically and functionally distinct pollinators. We examined whether geographical differentiation occurred for rewards, and whether this could be explained by spatially heterogeneous pollinator guilds and climate. Rewards were measured across the entire species range. Geographical patterns of reward quantity and their relationships with biotic and abiotic factors were examined using uni‐ and multivariate analyses. Latitude significantly explained population variation in nectar and oils, although in contrasting ways. Pollinator assemblages showed a prevalence of oil‐collecting Centris bees. Centris vardyorum, specialized on M. aphylla, showed a latitudinal pattern of visits. Oil production was not higher where plants associated with ecologically specialized bees (i.e. C. vardyorum), but this occurred instead where they were less frequent and co‐occurred with other bees that used many floral sources, including other plant species that produce oil. The multivariate analysis showed that the prevalence of C. vardyorum was the factor that contributed most significantly to the combined patterns of rewards. We suggest that large‐scale variation in rewards involves local optima throughout the species range, related to processes that operate in each ecoregion with their particular biotic and abiotic scenarios. © 2015 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 178 , 314–328.