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Showing papers in "Plant Ecology and Evolution in 2013"


Journal ArticleDOI
TL;DR: A flexible approach to understanding ‘petals’ is proposed requiring consideration of the origin of the floral organ, the functional role, evolutionary history of the organismal lineage, and consideration of developmental forces acting on the whole flower.
Abstract: Background and aims – The term ‘petal’ is loosely applied to a variety of showy non-homologous structures, generally situated in the second whorl of a differentiated perianth. Petaloid organs are extremely diverse throughout angiosperms with repeated derivations of petals, either by differentiation of a perianth, or derived from staminodes. The field of evo-devo has prompted re-analysis of concepts of homology and analogy amongst petals. Here the progress and challenges in understanding the nature of petals are reviewed in light of an influx of new data from phylogenetics, morphology and molecular genetics. Method and results – The complex web of homology concepts and criteria is discussed in connection to the petals, and terminology is subsequently defined. The variation and evolution of the perianth is then reviewed for the major clades of angiosperms. From this pan-angiosperm variation, we highlight and discuss several recurrent themes that complicate our ability to discern the evolution of the petal. In particular we emphasise the importance of developmental constraint, environmental stimuli, interrelationship between organs and cyclic patterns of loss and secondary gain of organs, and the development of a hypanthium or corona. Conclusions – A flexible approach to understanding ‘petals’ is proposed requiring consideration of the origin of the floral organ (stamen-derived or tepal-derived, or other), the functional role (sepaloid or petaloid organs), evolutionary history of the organismal lineage, and consideration of developmental forces acting on the whole flower. The variety and complex evolutionary history of the perianth may necessitate the exploration of petal development within phylogenetically quite restricted groups, combining data from morphology with evo-devo.

57 citations


Journal ArticleDOI
TL;DR: In this paper, the impact of forest biodiversity on forest ecosystem functioning has been studied, and it is shown that more biodiverse ecosystems have the potential to deliver more and better services.
Abstract: During the last two decades, functional biodiversity research has provided strong support for the hypothesis that more biodiverse ecosystems have the potential to deliver more and better services. However, most empirical support for this hypothesis comes from simple structured communities that are relatively easy to manipulate. The impact of forest biodiversity on forest ecosystem functioning has been far less studied.

45 citations



Journal ArticleDOI
TL;DR: Global variation in edaphic factors associated with variation in combinations of Edaphic parameters generates a highly heterogeneous environment favourable to a high diversity of plant communities over limited areas.
Abstract: Background and aims – In Katanga (D.R.Congo), outcrops of bedrocks naturally enriched in Cu and Co (“copper hills”), host unique plant communities. The spatial variation of vegetation has long been attributed almost exclusively to variation in Cu concentration in the soil, but this assumption has not been experimentally tested. We analysed the variation in plant communities and the niches of selected species in relation to edaphic factors within a copper hill. Methods – Forty-eight 1 m 2 plots were sampled for plant community and soil mineral element composition, and classified with Unweighted Pair Group Method with Arithmetic mean (UPGMA) using the Bray-Curtis distance. Plant-edaphic relationships were examined using a Canonical Correspondence Analysis (CCA). Species niches were modelled with Generalized Additive Model (GAM). Mean edaphic factors between the soil of plant communities were compared with one-way Kruskal-Wallis non-parametric ANOVA. Key results – The diversity of communities at the site scale was higher than observed in previous studies at a larger scale. Cu was the most discriminating edaphic factor of plant communities. However, detailed comparisons of mean edaphic factors among communities revealed individual combinations of edaphic parameters for each community, as well as differences in soil Cu content. High covariation appears to be an essential trait of the edaphic factor variation of Katangan Cu-rich soils. This makes it difficult to examine separately the effect of these factors on plant community structures. A bimodal pattern of niche distribution was found for Cu and pH. For physical parameters, niche optima were normally distributed. Conclusions – Global variation in edaphic factors associated with variation in combinations of edaphic parameters generates a highly heterogeneous environment favourable to a high diversity of plant communities over limited areas. Conservation strategies or restoration actions to limit the impact of mining activities on Cu-enriched ecosystems should pay special attention to recreate heterogeneity, taking into account the covariation of edaphic factors.

29 citations


Journal ArticleDOI
TL;DR: (Article begins on next page)
Abstract: (Article begins on next page) Anyone can freely access the full text of works made available as \"Open Access\". Works made available under a Creative Commons license can be used according to the terms and conditions of said license. Use of all other works requires consent of the right holder (author or publisher) if not exempted from copyright protection by the applicable law. Availability: This is the author's manuscript

25 citations



Journal ArticleDOI
TL;DR: Molecular data revealed that the real phylogenetic diversity of subaerial microalgae was probably grossly underestimated by traditional morphological taxonomy, and microscopy still provides the very core of current knowledge on ecology and distribution patterns ofSubaerial algae, including those in corticolous biofilms.
Abstract: Subaerial micro-algal biofilms growing on tree bark are omnipresent in a variety of ecosystems. However, terrestrial microhabitats have traditionally attracted far less attention from phycologists than marine and freshwater habitats, so their diversity and community structure is still very poorly known (Freystein & Reisser 2010, Rindi et al. 2010). Because of the lack of suitable discriminating characters and because species concepts are poor, species-level microscopic identification of most subaerial algae and Cyanobacteria is complicated (Ettl & Gartner 1995). In comparison to that of planktic and benthic communities, the morphological diversity of terrestrial microalgae is strikingly low; most taxa have coccoid spherical to oval cells, or simple filamentous thalli (Hoffmann 1989, Ettl & Gartner 1995). Consequently, most microscopic studies of subaerial assemblages have been based on either limited datasets acquired from approximate morphological identification of cultured strains (e.g. Nakano et al. 1991, Neustupa & Skaloud 2008), or direct observations of natural samples. Research on natural samples has typically been concentrated on several conspicuous groups, such as Trentepohliales, Klebsormidium, and Prasiola (e.g. Rindi & Guiry 2004, Hedenas et al. 2007). Recent molecular studies of subaerial microalgae have mostly been focused on phylogenetics and taxonomy of new and little-known microalgal and cyanobacterial lineages thriving in these microhabitats (Rindi et al. 2006, Zhang et al. 2008, Neustupa et al. 2013). They illustrated that the real phylogenetic diversity of subaerial microalgae was probably grossly underestimated by traditional morphological taxonomy. Molecular data revealed that the micro-algal communities of these habitats include numerous as yet unknown phylogenetic taxa. Some have been described as new micro-algal genera, such as Spongiochrysis, Heveochlorella, Hylodesmus, and Leptochlorella (Rindi et al. 2006, Zhang et al. 2008, Elias et al. 2010, Neustupa et al. 2013). Despite methodological limitations, microscopy still provides the very core of current knowledge on ecology and distribution patterns of subaerial algae, including those in corticolous biofilms. Tropical corticolous biofilms are often

18 citations




Journal ArticleDOI
TL;DR: The relatively high within-population diversities and moderate, although variable, between-population differentiation of the other Flemish populations point to a considerable amount of gene exchange and can justify extensive seed sourcing for the production of autochthonous planting stock.
Abstract: Background and aims : Seed sourcing on a local scale is an emerging awareness among nature conservationists. Guidelines should be tuned for woody species in highly anthropogenic landscapes such as Flanders (Belgium). We investigated the genetic variation within and between eight autochthonous Flemish Prunus spinosa populations and assessed their potential as seed source for gene conservation and ecological restoration. Methods and key results : All sampled sites were old hedges or wooded banks.Using AFLP, the overall gene diversity (H-t) was estimated at 0.13, with a low average between population diversity (H-b = 0.02) and a comparatively high average within-population diversity (H-w = 0.11).The genetic differentiation was remarkably variable among populations (Phi(ST) ranging from 0.07 to 0.43). There was no clear relationship between genetic and geographic distances, nor between genetic and morphometric characteristics. Only a small but significant correlation between endocarp and leaf morphological characters was observed. Conclusions : The variable genetic differentiation among populations points to different vegetation histories. Two populations, DEF and WES, were characterized by a dominant presence of sloe, high genetic differentiation from all other populations and low within-population diversities. No obvious morphometric variability of leaves could be related to these genetically deviating populations, however, WES showed a deviating endocarp morphology. Possibly, these two populationswere originally planted or supplemented using local and much related material whereas the others may have been planted with more diverse material. The relatively high within-population diversities and moderate, although variable, between-population differentiation of the other Flemish populations point to a considerable amount of gene exchange and can justify extensive seed sourcing for the production of autochthonous planting stock.These results stress the importance of a proper evaluation of genetic diversity for seed source selection and the need for regional field-applicable guidelines.

16 citations


Journal ArticleDOI
TL;DR: A botanical exploration was conducted between 2007 and 2011 in various regions of Cameroon and resulted in the discovery of several new national records and new species as discussed by the authors. But the inventory of Cameroon's flora is still incomplete and additional work is needed to document the country's extremely rich flora, and thus enhance its conservation.
Abstract: Background - The inventory of Cameroon's flora is far from complete and additional work is needed to document the country's extremely rich flora, and thus enhance its conservation. In this framework, botanical exploration was conducted between 2007 and 2011 in various regions of Cameroon and resulted in the discovery of several new national records and new species. Methods - Normal practices of herbarium taxonomy have been applied. For the endemic or subendemic species, a preliminary IUCN conservation has been proposed using the IUCN criteria. Results - A total of twelve taxa are recorded as new for the flora of Cameroon. Significant range extensions are reported for eight restricted-range species. A new species, Psychotria yaoundensis O.Lachenaud, endemic to Cameroon and only know from two rocky hills in the surroundings of Yaounde, is described and illustrated. Additions to the flora of Equatorial Guinea (five species), Nigeria, Ivory Coast and the Democratic Republic of Congo (one species each) are also reported. Psychotria moliwensis and Vangueriopsis gossweileri are synonymised under P. fernandopoensis and V. rubiginosa, respectively. Conclusion-Many areas within Cameroon remain botanically poorly explored. Our exploration highlights the importance of the Rumpi Hills, Tchabal Mbabo, and the rocky hills around Yaounde for plant conservation. Our data will help conservationists in determining areas highly valuable for conservation. © 2013 National Botanic Garden of Belgium and Royal Botanical Society of Belgium.

Journal ArticleDOI
TL;DR: The morphometric study revealed five distinct morphospecies that correspond to the concepts of the currently recognized species, with continental African members appearing to be most closely related to sect.
Abstract: Background and aims: Recent molecular studies suggest the polyphyly of Angraecum and the unnaturalness of some of its sections, as exemplified by sect. Pectinaria, which has species in two well-separated clades, one in Madagascar and the other in continental Africa. However, species delimitation among the five continental African members remained problematic due to morphological variability. In preparation for the taxonomic revision of this group, we used morphological and molecular data to re-assess the circumscription of each species, and to evaluate their monophyly and relationships to one another. Methods: A total of 59 alcohol-preserved specimens were used to perform multivariate analyses on 37 morphological characters. DNA sequences from one nuclear (ITS-1) and five plastid regions (matK, rps16, trnL – F, trnC – petN and ycf1) were analyzed using Parsimony and Bayesian methods. Key results: The morphometric study revealed five distinct morphospecies that correspond to the concepts of the currently recognized species. Angraecum doratophyllum and A. subulatum are the most distinct morphologically, whereas A. atlanticum, A. gabonense and A. pungens are most similar to one another. Phylogenetic analyses using a combined data set of the six markers yielded highly resolved, congruent trees with strong branch support. The polyphyly of A. sect. Pectinaria is confirmed, with continental African members appearing to be most closely related to sect. Dolabrifolia, found exclusively in Africa. The multiple accessions of A. doratophyllum, A. gabonense, A. pungens and A. subulatum each formed a well-supported clade. Parsimony and Bayesian analyses placed A. atlanticum and A. pungens in a subclade within which samples of A. pungens were nested but those of A. atlanticum formed a grade. These two species can be easily distinguished morphologically by leaf dimensions and flower length, but broader sampling in continental Africa is needed to test whether individuals recognized as A. atlanticum might represent two distinct taxa.



Journal ArticleDOI
TL;DR: The treatment of Uapaca (Phyllanthaceae) for the Flore du Gabon revealed many, hitherto unknown, synonymies and some overlooked names that deserve a separate publication.
Abstract: The treatment of Uapaca (Phyllanthaceae) for the Flore du Gabon revealed many, hitherto unknown, synonymies and some overlooked names that deserve a separate publication. Advantage is taken of this treatment to establish the geography of the forest species on an African scale.

Journal ArticleDOI
TL;DR: A new species of Rubiaceae, Psychotria wieringae O. lachenaud, endemic to the Libreville peninsula (Gabon) is described and illustrated and considered as Endangered EN B2ab(i,ii,iii,iv,v) according to IUCN criteria.
Abstract: Background - A new species of Rubiaceae, Psychotria wieringae O.Lachenaud, is described and illustrated. Methods-Normal practises of herbarium taxonomy have been applied. Key results - P. wieringae is endemic to the Libreville peninsula (Gabon), where it is locally abundant in the undergrowth of littoral forests on sandy soils. It is related to P. gabonica Hiern but differs in its pale bark, glabrous inflorescences, flower colour, and leaves with a prominent midrib on the upper surface. IUCN assessment - The species is considered as Endangered EN B2ab(i,ii,iii,iv,v) according to IUCN criteria. Its survival in situ will likely depend on the maintenance of the subpopulation at the "Ferme des crocodiles", situated in the Raponda-Walker Arboretum. The occurence of several other endemic species in the area, and their conservation, are also discussed. © 2013 National Botanic Garden of Belgium and Royal Botanical Society of Belgium.

Journal ArticleDOI
TL;DR: Five new species of Psychotria (Rubiaceae) from West Africa are described and illustrated, in the framework of a regional revision of the genus, with a remarkable adaptation in various Angiosperm families in the African rainforests.
Abstract: Background - Five new species of Psychotria (Rubiaceae) from West Africa are described and illustrated, in the framework of a regional revision of the genus. Methods - Normal practices of herbarium taxonomy have been applied. Key results - Three of the new species, Psychotria baldwinii, P. tetragonopus and P. voorhoevei, are endemic to Liberia, while the other two, P. blydeniae and P. rubriceps, also occur in adjacent southwestern Cote d'Ivoire. The Ivorian endemic Psychotria copeensis, previously included in the synonymy of P. subobliqua, is separated as a distinct species. Psychotria blydeniae and P. tetragonopus are litterbin plants.we discuss this remarkable adaptation and its occurrence in various Angiosperm families in the African rainforests. © 2013 National Botanic Garden of Belgium and Royal Botanical Society of Belgium.

Journal ArticleDOI
TL;DR: The European Union’s Water Framework Directive (2000/60/ EC) was established as a framework for community action in the field of water policy to achieve ‘good quality’ status for all surface waters throughout Europe by 2015.
Abstract: The European Union’s Water Framework Directive (2000/60/ EC) was established as a framework for community action in the field of water policy (EU 2000). Its general objective is to achieve ‘good quality’ status for all surface waters throughout Europe by 2015. Water status monitoring programmes use both chemical and biological elements to assess water quality (Allan et al. 2006). Although chemical analyses are routinely used technique, this approach has several disadvantages, e.g. underestimation of variations occurring over short periods (Marker & Collet 1991) or the inability to detect all trace organic pollutants (Whitton 1991). Therefore, monitoring of indicator organisms has begun to be an important part of water management (Whitton & Kelly 1995, EU 2000). Algae respond rapidly to various pollutants and provide useful early warning signals about deteriorating ecosystem conditions (McCormick & Cairns 1994). Diatoms (Bacillariophyta) are routinely used algal indicators, which have a clear relationship to water quality (Cox 1991, Round 1991, Reid et al. 1995) and reflect environmental stress through shifts in the community species composition (Rott 1991). For taxonomic identifications, comprehensive diatom keys are available (e.g. Krammer & Lange-Bertalot 1986, 1988, 1991a, 1991b, Lange-Bertalot 2001, Krammer 2000, 2002, 2003), although recent diatom taxonomy is rather complicated due to the existence of many cryptic species and problematic spe-


Journal ArticleDOI
TL;DR: High phenotypic variation in S. repens at intraspecific level in response to contrasting environmental conditions reflects a two-fold strategy common in epiphytes: increase water storage and reduce water loss, suggesting that leaf succulence has an adaptive value even in a temperate cold rainforest.
Abstract: Background and aims – Succulence, a common attribute of floras in dry regions and of species living in microenvironments with transient water shortage, has been typically viewed as an adaptive plant feature for surviving in (semi-)arid conditions. The existence of leaf succulence in a temperate cold rainforest challenges the view of its adaptive value. We studied leaf functional variation in Sarmienta repens Ruiz & Pav. (Gesneriaceae), an epiphyte living in the Valdivian forest of southern Chile. Material and methods – We measured leaf thickness, absolute leaf water content, specific leaf area and leaf anatomy (epidermis, palisade parenchyma, and spongy parenchyma) in two distinct light microenvironments: shaded understory versus border of canopy gaps. We also characterized micro-environmental conditions in terms of light availability, temperature and water evaporation. Key results – We show that leaves from sun conditions, the environment with higher water demand, have lower SLA (specific leaf area), thicker epidermis and store more water due to a thicker spongy parenchyma, than leaves from shade conditions. Conclusions – We found high phenotypic variation in S. repens at intraspecific level in response to contrasting environmental conditions. This variation reflects a two-fold strategy common in epiphytes: increase water storage and reduce water loss. Furthermore, it suggests that leaf succulence has an adaptive value even in a temperate cold rainforest. We discuss that the occurrence of succulence on a cold rainforest might be explained by a combination of ecological, biogeographic and phylogenetic factors.




Journal ArticleDOI
TL;DR: Microscopical investigation yielded multispored asci, a chlorococcoid photobiont and the presence in the epihymenium of an orange substance that reacted K+ purplish, which led us to consider the specimens from Reunion Island to represent an additional new species.
Abstract: Piccolia A.Massal. is a very small genus of crustose lichens with only six species currently accepted. It is characterized by multispored asci, a chlorococcoid photobiont and the presence of anthraquinone pigments in the apothecia (Hafellner 1995, Smith et al. 2009). Hafellner (1995) removed the genus Piccolia A.Massal. from synonymy with Biatorella De Not., recognizing four species. Recently Knudsen & Lendemer (2007) transferred B. nannaria (Tuck.) Zahlbr. to P. nan­ naria (Tuck.) Lendemer & Beeching and Hafellner (2004) transferred Strangospora ochrophora (Nyl.) R.A.Anderson to P. ochrophora (Nyl.) Hafellner. No molecular data are available so far, so that the taxonomic position of the genus is uncertain. The current version of Myconet includes Pic­ colia as a genus incertae sedis within the Lecanoromycetes (Lumbsch & Huhndorf 2010). Four of the species, P. elmeri (Vain.) Hafellner, P. hae­ matina (Mull. Arg.) Hafellner, P. nannaria (Tuck.) Lendemer & Beeching and P. wrightii (Tuck.) Hafellner, are restricted to tropical and subtropical regions. The widely distributed P. conspersa (Fee) Hafellner reaches also warm temperate regions and P. ochrophora (Nyl.) Hafellner occurs throughout Europe as well as in North and South America (Hafellner 1995, 2004, Knudsen & Lendemer 2007). During a collection trip in D.R.Congo in 2009, one of us (D.E.) discovered a crustose lichen with conspicuous apothecia. Microscopical investigation yielded multispored asci, a chlorococcoid photobiont and the presence in the epihymenium of an orange substance that reacted K+ purplish. During a new expedition in 2012 (COBIMFO project) a second specimen was discovered by the first author. A comparison with herbarium specimens of P. elmeri led us to consider the specimens from Reunion Island (van den Boom et al. 2011) to represent an additional new species. The third species, P. nivea, was found on the Solomon Islands and send to us by the second author.


Journal ArticleDOI
TL;DR: Rhipidoglossum montealenense Descourvieres, Stevart & P.J.Cribb sp.
Abstract: Background and aims - While conducting a taxonomic revision of the genera Diaphananthe and Rhipidoglossum (Orchidaceae), a new taxon from Equatorial Guinea and Cameroon was discovered, and is formally described here. Methods - A comparison of about 800 specimens with the nomenclatural types and the specimens housed at BR, BRLU, K, P, WAG and YA herbaria was undertaken in order to confirm the taxonomical status of the new taxon. Its conservation status was assessed using the IUCN Red List Categories and Criteria. Key results - Rhipidoglossum montealenense Descourvieres, Stevart & P.J.Cribb sp. nov., here described and illustrated, is endemic to Rio Muni (Equatorial Guinea) and southern Cameroon. The species is found in the mountainous area situated along the transition from the coastal and to the continental regions of Atlantic Central Africa. It is close to R. melianthum but differs by its decurrent petals, a small ovary and a comparatively short spur. The species also differs from R. paucifolium by its elliptical lip lacking a callus and by rounded to subacute sepals and petals, and from R. rutilum by its short leaf internodes. The species is considered as Endangered according to IUCN Categories and Criteria. Its survival in situ will likely depend on the maintenance of the subpopulation in the Monte Alen National Park. © 2013 National Botanic Garden of Belgium and Royal Botanical Society of Belgium.


Journal ArticleDOI
TL;DR: A new combination, Cyperus steudneri (Boeckeler) Larridon is proposed for Kyllingiella polyphylla (A.Rich.) Lye.
Abstract: The recently published nomen novum Cyperus spiralis Larridon is illegitimate, because an earlier epithet of a homotypic name is available. A new combination, Cyperus steudneri (Boeckeler) Larridon is proposed for Kyllingiella polyphylla (A.Rich.) Lye.

Journal ArticleDOI
TL;DR: The genus Idertia is characterized by a gynobasic style, apocarpous fruits, ten stamens, persistent and accrescent sepals and intra-axillary fused stipules, which renders it distinct from its African relatives Campylospermum and Rhabdophyllum.
Abstract: Background and aims - The genus Idertia belongs to the subfamily Ochnoideae, tribe Ochneae, subtribe Ouratinae. This paper aims at a full taxonomic revision and a critical evaluation of the taxonomic position of the genus along with its diagnostic characters. Methods - All characters are studied using 73 herbarium collections of the following herbaria: B, BM, BR, BRLU, COI, EA, G, K, MO, P and WAG. Specimen data were managed using the BRAHMS herbarium management software. Key results - Idertia is characterized by a gynobasic style, apocarpous fruits, ten stamens, persistent and accrescent sepals and intra-axillary fused stipules. It shares these features with its African relatives Campylospermum and Rhabdophyllum, but its axillary inflorescence, smooth anthers and straight cotyledons renders it distinct. The latter feature is reminiscent of the South American relative Ouratea which lacks the persistent sepals and has free lateral stipules. Other diagnostic characters of the wood, leaves, inflorescence, flowers and fruits are discussed. A key to the four genera of the subtribe Ouratinae is provided. The correct author combination for the name Ouratinae is (Engl.) Kanis. The variation amongst the four species of Idertia recognized by other authors was studied carefully and deemed continuous. Only a single, though variable species distributed from Guinea to Uganda is recognized. A full taxonomic treatment is provided and two lectotypes are designated. Conclusions - Idertia is a well-defined and sufficiently distinct monotypic genus.

Journal ArticleDOI
TL;DR: It is proposed that four species should be recognized in the G. superba complex, based on habit, inflorescence characters and distribution patterns, which is the most widespread taxon, occurring in South Africa, tropical Africa and Asia.
Abstract: Background and aims - Gloriosa superba L. is a highly variable species occurring in a wide range of ecological habitats in South Africa, tropical Africa and Asia. The morphological variation in G. superba was found to be complicated and therefore numerical methods were used to re-evaluate morphological variation and species delimitation in the G. superba complex. Methods - This study was based on 79 herbarium specimens from B, BM, BR, C, COI, F, K, L, SRGH, U, UPS and WAG (abbreviations follow Holmgren et al. 1990). Cluster and ordination analyses were used to explore morphological variation within the study group. The morphometric data set based on both qualitative and quantitative characters was entered directly into a computerized matrix and a cluster analysis was computed using NTSYS package. The variability of individual characters was evaluated by box-plots using SPSS. Key results & conclusions - The morphological study has revealed the existence of four phenetic species in the G. superba complex. Recognition of these species is based on habit, inflorescence characters and distribution patterns. It is here proposed that four species should be recognized in the G. superba complex: G. baudii (Terracc.) Chiov., G. carsonii Baker, G. superba L. and G. simplex L. Gloriosa superba is the most widespread taxon, occurring in South Africa, tropical Africa and Asia. Gloriosa simplex, G. carsonii and G. baudii are confined to the African continent, with G. simplex widespread in tropical Africa, G. carsonii common in south, central to east tropical Africa, and G. baudii having the most restricted range, confined to the arid regions of northern Kenya, Ethiopia and Somalia.