Juan Lorite

Assessing extinction-risk of endangered plants using species distribution models: a case study of habitat depletion caused by the spread of greenhouses

The species distribution models (SDMs) are useful tools for investigating rare and endangered species as well as the environmental variables affecting them. In this paper, we propose the application of SDMs to assess the extinction-risk of plant species in relation to the spread of greenhouses in a Mediterranean landscape, where habitat depletion is one of the main causes of biodiversity loss. For this purpose, presence records of the model species (Linaria nigricans, a endemic and threatened species) and the greenhouses, a dataset of environmental variables, and different only presence-based modelling algorithms (Bioclim, Domain, GARP, MaxEnt and ENFA) were used to build SDMs for L. nigricans as well as for greenhouses. To evaluate the models a modified approach of the area-under-curve ROC was applied. Combining the most accurate models, we generated an extinction-risk model of L. nigricans populations, which enabled us to assess the sustainability of the most threatened populations. Our results show that is possible to model greenhouses spreading as a “biological invasion”. The procedure explained and used in this work is quite novel, and offers an objective spatial criterion intended for the management of natural resources and for the conservation of the biodiversity in areas threatened by habitat depletion processes as particular as greenhouses expansion.

Evolution of pollination niches and floral divergence in the generalist plant Erysimum mediohispanicum

BACKGROUND AND AIMS How generalist plants diverge in response to pollinator selection without becoming specialized is still unknown. This study explores this question, focusing on the evolution of the pollination system in the pollination generalist Erysimum mediohispanicum (Brassicaceae). METHODS Pollinator assemblages were surveyed from 2001 to 2010 in 48 geo-referenced populations covering the entire geographic distribution of E. mediohispanicum. Bipartite modularity, a complex network tool, was used to find the pollination niche of each population. Evolution of the pollination niches and the correlated evolution of floral traits and pollination niches were explored using within-species comparative analyses. KEY RESULTS Despite being generalists, the E. mediohispanicum populations studied can be classified into five pollination niches. The boundaries between niches were not sharp, the niches differing among them in the relative frequencies of the floral visitor functional groups. The absence of spatial autocorrelation and phylogenetic signal indicates that the niches were distributed in a phylogeographic mosaic. The ancestral E. mediohispanicum populations presumably belonged to the niche defined by a high number of beetle and ant visits. A correlated evolution was found between pollination niches and some floral traits, suggesting the existence of generalist pollination ecotypes. CONCLUSIONS It is conjectured that the geographic variation in pollination niches has contributed to the observed floral divergence in E. mediohispanicum. The process mediating this floral divergence presumably has been adaptive wandering, but the adaptation to the local pollinator faunas has been not universal. The outcome is a landscape where a few populations locally adapted to their pollination environment (generalist pollination ecotypes) coexist with many populations where this local adaptation has failed and where the plant phenotype is not primarily shaped by pollinators.

Using complementary techniques to distinguish cryptic species: A new Erysimum (Brassicaceae) species from North Africa

PREMISE OF THE STUDY Cryptic species are superficially morphologically indistinguishable and therefore erroneously classified under one single name. The identification and delimitation of these species is usually a difficult task. The main aim of this study is to provide an inclusive methodology that combines standard and new tools to allow accurate identification of cryptic species. We used Erysimum nervosum s.l. as a model system. METHODS Four populations belonging to E. nervosum s.l. were sampled at their two distribution ranges in Morocco (the Atlas Mountains and the Rif Mountains). Fifteen individuals per population were collected to assess standard taxonomic traits. Additionally, corolla color and shape were quantified in 30 individuals per population using spectrophotometry and geometric morphometrics, respectively. Finally, we collected tissue samples from each population per species to study the phylogenetic relationships among them. KEY RESULTS Using the standard taxonomic traits, we could not distinguish the four populations. Nonetheless, there were differences in corolla color and shape between plants from the two mountain ranges. The population differentiation based on quantitative morphological differences were confirmed and supported by the phylogenetic relationships obtained for these populations and the rest of the Moroccan Erysimum species. CONCLUSIONS The joint use of the results obtained from standard taxonomic traits, quantitative analyses of plant phenotype, and molecular data suggests the occurrence of two species within E. nervosum s.l. in Morocco, one located in the Atlas Mountains (E. nervosum s.s.) and the other in the Rif Mountains (E. riphaeanum sp. nov.). Consequently, we suggest that combining quantitative and molecular approaches with standard taxonomy greatly benefits the identification of cryptic species.

Estimation of threatened orophytic flora and priority of its conservation in the Baetic range (S. Spain)

Abstract The Baetic range (SE Spain) constitutes an important centre of diversity and speciation in the Mediterranean Basin. However, numerous species are threatened by different human activities and by global climatic change. In this work, we provide data on the conservational state of orophilous plants of the Baetic range and propose priorities for their protection. For this, we analysed 82 threatened taxa and 17 mountain areas using correspondence analysis (CA) and complementarity analysis. Of the 2,197.5 km2 of high-mountain areas analysed, only 1,654.5 km2 are currently protected (75.3%). Of the 82 threatened species, 16 have no type of protection, eight are critically endangered and six are endangered (according to the categories of the UICN): Overgrazing and natural causes are the main factors threatening most of the species. The Sierra Nevada mountain (Granada and Almería provinces) and Cazorla-Segura mountain (Jaén province) provide protection for 67.5% of the total number of threatened orophilous species, and 71.7% of the species evaluated as critically endangered. We propose Gádor and Sagra mountains as new priority areas for the conservation of threatened orophilous flora.

Macrofungi diversity in cork-oak and holm-oak forests in Andalusia (southern Spain); an efficient parameter for establishing priorities for its evaluation and conservation

In this work, the fungal diversity of holm-oak and cork-oak woodlands in southern Spain is studied in order to analyse the macrofungi component and its ecological characteristics, as well as to establish priorities for its conservation. For this, we have compiled published as well as unpublished data, and applied compositional analysis and statistical methods (basic statistics, non-parametric and multivariate analyses). Priority areas were selected based on complementarity analysis. As a result, 838 taxa were recorded, 78.6% in cork-oak and 76.4% in holm-oak forests, with 55.1% in common. The ratio of mycorrhizal to saprophitic species indicated that cork-oak woodlands present a higher diversity and conservation degree of its macrofungal community than holm-oak woodlands, since the mycorrhizal component is more important for the conservation of these forests (due to nutritional relations). Both forests types appear well differentiated in the multivariate analysis. In the complementarity analysis, with only one site, we recorded 40% of the total species encountered. The percentage increased to 80% with four sites. This type of approach, by highlighting the important areas for conservation of fungal diversity, constitutes a powerful tool to optimise conservation efforts.

Evolution of pollination niches in a generalist plant clade.

It is widely assumed that floral diversification occurs by adaptive shifts between pollination niches. In contrast to specialized flowers, identifying pollination niches of generalist flowers is a challenge. Consequently, how generalist pollination niches evolve is largely unknown. We apply tools from network theory and comparative methods to investigate the evolution of pollination niches among generalist species belonging to the genus Erysimum. These species have similar flowers. We found that the studied species may be grouped in several multidimensional niches separated not by a shift of pollinators, but instead by quantitative variation in the relative abundance of pollinator functional groups. These pollination niches did not vary in generalization degree; we did not find any evolutionary trend toward specialization within the studied clade. Furthermore, the evolution of pollination niche fitted to a Brownian motion model without phylogenetic signal, and was characterized by frequent events of niche convergences and divergences. We presume that the evolution of Erysimum pollination niches has occurred mostly by recurrent shifts between slightly different generalized pollinator assemblages varying spatially as a mosaic and without any change in specialization degree. Most changes in pollination niches do not prompt floral divergence, a reason why adaptation to pollinators is uncommon in generalist plants.

The role of pollinators in floral diversification in a clade of generalist flowers

Pollinator‐mediated evolutionary divergence has seldom been explored in generalist clades because it is assumed that pollinators in those clades exert weak and conflicting selection. We investigate whether pollinators shape floral diversification in a pollination generalist plant genus, Erysimum. Species from this genus have flowers that appeal to broad assemblages of pollinators. Nevertheless, we recently reported that it is possible to sort plant species into pollination niches varying in the quantitative composition of pollinators. We test here whether floral characters of Erysimum have evolved as a consequence of shifts among pollination niches. For this, we quantified the evolutionary lability of the floral traits and their phylogenetic association with pollination niches. As with pollination niches, Erysimum floral traits show weak phylogenetic signal. Moreover, floral shape and color are phylogenetically associated with pollination niche. In particular, plants belonging to a pollination niche dominated by long‐tongued large bees have lilac corollas with parallel petals. Further analyses suggest, however, that changes in color preceded changes in pollination niche. Pollinators seem to have driven the evolution of corolla shape, whereas the association between pollination niche and corolla color has probably arisen by lilac‐flowered Erysimum moving toward certain pollination niches for other adaptive reasons.

The role of pollinators in the evolution of corolla shape variation, disparity and integration in a highly diversified plant family with a conserved floral bauplan.

BACKGROUND AND AIMS Brassicaceae is one of the most diversified families in the angiosperms. However, most species from this family exhibit a very similar floral bauplan. In this study, we explore the Brassicaceae floral morphospace, examining how corolla shape variation (an estimation of developmental robustness), integration and disparity vary among phylogenetically related species. Our aim is to check whether these floral attributes have evolved in this family despite its apparent morphological conservation, and to test the role of pollinators in driving this evolution. METHODS Using geometric morphometric tools, we calculated the phenotypic variation, disparity and integration of the corolla shape of 111 Brassicaceae taxa. We subsequently inferred the phylogenetic relationships of these taxa and explored the evolutionary lability of corolla shape. Finally, we sampled the pollinator assemblages of every taxon included in this study, and determined their pollination niches using a modularity algorithm. We explore the relationship between pollination niche and the attributes of corolla shape. KEY RESULTS Phylogenetic signal was weak for all corolla shape attributes. All taxa had generalized pollination systems. Nevertheless, they belong to different pollination niches. There were significant differences in corolla shape among pollination niches even after controlling for the phylogenetic relationship of the plant taxa. Corolla shape variation and disparity was significantly higher in those taxa visited mostly by nocturnal moths, indicating that this pollination niche is associated with a lack of developmental robustness. Corolla integration was higher in those taxa visited mostly by hovering long-tongued flies and long-tongued large bees. CONCLUSIONS Corolla variation, integration and disparity were evolutionarily labile and evolved very recently in the evolutionary history of the Brassicaceae. These floral attributes were strongly related to the pollination niche. Even in a plant clade having a very generalized pollination system and exhibiting a conserved floral bauplan, pollinators can drive the evolution of important developmental attributes of corolla shape.

Mycorrhizal macrofungi diversity (Agaricomycetes) from Mediterranean Quercus forests; a compilation for the Iberian Peninsula (Spain and Portugal).

A compilation study has been made of the mycorrhizal Agaricomycetes from several sclerophyllous and deciduous Mediterranean Quercus woodlands from Iberian Peninsula. Firstly, we selected eight Mediterranean taxa of the genus Quercus, which were well sampled in terms of macrofungi. Afterwards, we performed a database containing a large amount of data about mycorrhizal biota of Quercus. We have defined and/or used a series of indexes (occurrence, affinity, proportionality, heterogeneity, similarity, and taxonomic diversity) in order to establish the differences between the mycorrhizal biota of the selected woodlands. The 605 taxa compiled here represent an important amount of the total mycorrhizal diversity from all the vegetation types of the studied area, estimated at 1,500–1,600 taxa, with Q. ilex subsp. ballota (416 taxa) and Q. suber (411) being the richest. We also analysed their quantitative and qualitative mycorrhizal flora and their relative richness in different ways: woodland types, substrates and species composition. The results highlight the large amount of mycorrhizal macrofungi species occurring in these mediterranean Quercus woodlands, the data are comparable with other woodland types, thought to be the richest forest types in the world. We point out that the presence of genera that are very well adapted to sclerophyllous Mediterranean woodlands with a potential use in afforestation or recovery programs, or being rare species, are listed in the Regional Red List of Endangered Macromycetes. Since, these woodlands suffer heavy environmental pressure, human and climate mediated, we conclude many species are approaching a high extinction risk, and it is urgent to apply legal and management measures, both,of national (Spain and Portugal) and European governments.

Conservation status of the first known population of Polygala balansae in Europe.

We studied the natural history as well as the conservation status of the first-known population of Polygala balansae in Europe (Granada, SE Spain). In the study area, we located only one population occupying a small patch of 1920 m2, between 120 and 160 m a.s.l., with 246 mature individuals. The species is classified as Critically Endangered (CR), under the following criteria: severely fragmented, inferred continuous decline, small population size, and continuing decline inferred from the number mature individuals. The main threats over the population are: spreading subtropical tree-crops and encroachment of human settlements for tourist purposes, plus natural causes (drought, wild or human-mediated fire, limited dispersal, poor recruitment/ reproduction/regeneration, high juvenile mortality, low densities and restricted range). Finally, passive and active conservation measures are proposed in order to guarantee the survival of the species.