Present, past and future of the European rock fern Asplenium fontanum: combining distribution modelling and population genetics to study the effect of climate change on geographic range and genetic diversity.

BACKGROUND AND AIMS: Climate change is expected to alter the geographic range of many plant species dramatically. Predicting this response will be critical to managing the conservation of plant resources and the effects of invasive species. The aim of this study was to predict the response of temperate homosporous ferns to climate change. METHODS: Genetic diversity and changes in distribution range were inferred for the diploid rock fern Asplenium fontanum along a South-North transect, extending from its putative last glacial maximum (LGM) refugia in southern France towards southern Germany and eastern-central France. This study reconciles observations from distribution models and phylogeographic analyses derived from plastid and nuclear diversity. KEY RESULTS: Genetic diversity distribution and niche modelling propose that genetic diversity accumulates in the LGM climate refugium in southern France with the formation of a diversity gradient reflecting a slow, post-LGM range expansion towards the current distribution range. Evidence supports the fern's preference for outcrossing, contradicting the expectation that homosporous ferns would populate new sites by single-spore colonization. Prediction of climate and distribution range change suggests that a dramatic loss of range and genetic diversity in this fern is possible. The observed migration is best described by the phalanx expansion model. CONCLUSIONS: The results suggest that homosporous ferns reproducing preferentially by outcrossing accumulate genetic diversity primarily in LGM climate refugia and may be threatened if these areas disappear due to global climate change.

A new R package to parse plant species occurrence records into unique collection events efficiently reduces data redundancy.

Biodiversity data aggregators, such as Global Biodiversity Information Facility (GBIF) suffer from inflation of the number of occurrence records when data from different databases are merged but not fully reconciled. The ParseGBIF workflow is designed to parse duplicate GBIF species occurrence records into unique collection events (gatherings) and to optimise the quality of the spatial data associated with them. ParseGBIF provides tools to verify and standardize species scientific names according to the World Checklist of Vascular Plants taxonomic backbone, and to parse duplicate records into unique 'collection events', in the process compiling the most informative spatial data, where more than one duplicate is available, and providing crude estimates of taxonomic and spatial data quality. When GBIF occurrence records for a medium-sized vascular plant family, the Myrtaceae, were processed by ParseGBIF, the average number of records useful for spatial analysis increased by 180%. ParseGBIF could therefore be valuable in the evaluation of species' occurrences at the national scale in support for national biodiversity plans, identification of plant areas important for biodiversity, sample bias estimation to inform future sampling efforts, and to forecast species range shifts in response to global climate change.

Colombia's bioregions as a source of useful plants.

The aim of our study was to assess the importance of different Colombian bioregions in terms of the supply of useful plant species and the quality of the available distribution data. We assembled a dataset of georeferenced collection localities of all vascular plants of Colombia available from global and local online databases. We then assembled a list of species, subspecies and varieties of Colombia's useful plants and retrieved all point locality information associated with these taxa. We overlaid both datasets with a map of Colombia's bioregions to retrieve all species and useful species distribution records in each bioregion. To assess the reliability of our estimates of species numbers, we identified information gaps, in geographic and environmental space, by estimating their completeness and coverage. Our results confirmed that Colombia's third largest bioregion, the Andean moist forest followed by the Amazon, Pacific, Llanos and Caribbean moist forests contained the largest numbers of useful plant species. Medicinal use was the most common useful attribute across all bioregions, followed by Materials, Environmental uses, and Human Food. In all bioregions, except for the Andean páramo, the proportion of well-surveyed 10×10 km grid cells (with ≥ 25 observation records of useful plants) was below 50% of the total number of surveyed cells. Poor survey coverage was observed in the three dry bioregions: Caribbean deserts and xeric shrublands, and Llanos and Caribbean dry forests. This suggests that additional primary data is needed. We document knowledge gaps that will hinder the incorporation of useful plants into Colombia's stated plans for a bioeconomy and their sustainable management. In particular, future research should focus on the generation of additional primary data on the distribution of useful plants in the Amazon and Llanos (Orinoquia) regions where both survey completeness and coverage appeared to be less adequate compared with other regions.

A Preliminary Evaluation of The Karst Flora of Brazil Using Collections Data.

Karst is defined as landscapes that are underlain by soluble rock in which there is appreciable water movement arising from a combination of high rock solubility and well-developed secondary (fracture) porosity. Karsts occupy approximately 20% of the planet's dry ice-free land and are of great socioeconomic importance, as they supply water to up to 25% of the world's population and represent landscapes of cultural and touristic importance. In Southeast Asia karst is associated with high species-richness and endemism in plants and seen as priority areas for the conservation of biodiversity. There has been little research into the floras associated with karst in South America, most of which occurs in Brazil. We therefore sought to evaluate the importance of Brazilian karst with respect to its species-richness and endemism. We sought to do so using curated plant specimen data in the Botanical Information and Ecology Network (BIEN) dataset. We show that, except for Amazonia, the BIEN dataset is representative of the Brazilian flora with respect to the total number of species and overall patterns of species richness. We found that karst is under-sampled, as is the case for much of Brazil. We also found that whilst karst represent an important source of plant diversity for Brazil, including populations of approximately 1/3 of the Brazilian flora, it is not significantly more species-rich or richer in small-range and endemic species than surrounding landscapes. Similarly, whilst important for conservation, comprising populations of 26.5-37.4% of all Brazilian species evaluated as of conservation concern by International Union for Nature Conservation (IUCN), karst is no more so than the surrounding areas. Whilst experimental error, including map resolution and the precision and accuracy of point data may have under-estimated the species-richness of Brazilian karst, it likely represents an important biodiversity resource for Brazil and one that can play a valuable role in conservation. Our findings are in sharp contrast to those for Southeast Asia where karst represents a more important source of species-richness and endemism. We also show that although BIEN represents a comprehensive and curated source of point data, discrepancies in the application of names compared to current more comprehensive taxonomic backbones, can have profound impacts on estimates of species-richness, distribution ranges and estimates of endemism.

Neoendemism in Madagascan scaly tree ferns results from recent, coincident diversification bursts.

More than 80% of Madagascar's 12,000 plant species are endemic with the degree of endemism reaching as much as 95% in the scaly tree ferns, an important species rich component of Madagascar's evergreen rainforests. Predominantly African or Asian ancestry and divergence times usually postdating the separation of Madagascar from the Gondwanan landmasses have been demonstrated for several Madagascan animal and angiosperm groups. However, evolutionary studies of rainforest-specific lineages are scarce and the ecological context of radiation events has rarely been investigated. Here, we examine the evolution of Madagascan tree ferns as a rainforest-specific model family, integrate results from bioclimatic niche analysis with a dated phylogenetic framework, and propose an evolutionary scenario casting new light on our knowledge of the evolution of large island endemic clades. We show that Madagascar's extant tree fern diversity springs from three distinct ancestors independently colonizing Madagascar in the Miocene and that these three monophyletic clades diversified in three coincident radiation bursts during the Pliocene, reaching exceptionally high diversification rates and most likely responding to a common climatic trigger. Recent diversification bursts may thus have played a major role in the evolution of the extant Madagascan rainforest biome, which hence contains a significant number of young, neoendemic taxa.

Discovery of a diverse cave flora in China.

Few studies document plants in caves. Our field observations of a widespread and seemingly angiosperm-rich cave flora in SW China lead us to test the following hypotheses, 1) SW China caves contain a diverse vascular plant flora, 2) that this is a relic of a largely absent forest type lacking endemic species, and 3) that the light environment plants occupy in caves is not distinct from non-cave habitats. To do so we surveyed 61 caves and used species accumulation curves (SAC) to estimate the total diversity of this flora and used a subsample of 14 caves to characterise the light environment. We used regional floras and existing conservation assessments to evaluate the conservation value of this flora. We used observations on human disturbance within caves to evaluate anthropogenic activities. Four-hundred-and-eighteen vascular plant species were documented with SACs predicting a total diversity of 529-846. Ninety-three percent of the species documented are known karst forest species, 7% are endemic to caves and 81% of the species are angiosperms. We demonstrate that the light environment in caves is distinct to that of terrestrial habitats and that a subset of the flora likely grow in the lowest light levels documented for vascularised plants. Our results suggest that the proportion of species threatened with extinction is like that for the terrestrial habitat and that almost half of the entrance caverns sampled showed signs of human disturbance. We believe that this is the first time that such an extensive sample of cave flora has been undertaken and that such a diverse vascular plant flora has been observed in caves which we predict occurs elsewhere in SE Asia. We argue that the cave flora is an extension of the karst forest understory present prior to catastrophic deforestation in the 20thC. We suggest that within SW China caves serve as both refuges and a valuable source of germplasm for the restoration of karst forest. We also propose that caves represent a distinct habitat for plants that is most similar to that of the forest understory, but distinct with respect to the absence of trees, leaf litter, root mats, higher levels of atmospheric CO2, and lower diurnal and annual variation in temperature and humidity. We highlight tourism, agriculture and the absence of legislated protection of caves as the main current threats to this flora.

Phylogeography of the Sino-Himalayan fern Lepisorus clathratus on "the roof of the world".

BACKGROUND: The Qinghai-Tibetan Plateau (QTP) and its southern and southeastern mountain ranges, Himalaya-Hengduan Mountains (HHM), are one of the most extensive habitats for alpine plants in the world. How ferns occurring in QTP and HHM changed their distribution ranges in response to Quaternary climatic oscillations remains almost unknown. METHODOLOGY AND RESULTS: We employed sequences of two chloroplast DNA regions, rps4-trnS and trnL-trnF, to reconstruct phylogeography of the Sino-Himalayan fern Lepisorus clathratus, occurring mainly in the QTP and HHM. Individuals of this species have either dehiscent or indehiscent sporangia with the latter evolved from the plesiomorphic dehiscent forms. Based on a range-wide sampling, we detected 27 cpDNA haplotypes that were divided into five groups by network analyses. Populations in the Hengduan Mountains possess the highest genetic diversity, while a single haplogroup is detected across the north-central region. A distinct phylogeographical subdivision was detected between the Hengduan Mountains and north-central region by AMOVA analysis. The haplogroup distribution pattern, coalescence and AMOVA analysis suggest that a long term survival area (refugia) of the species was located in the Hengduan Mountains during glaciations, with probable range expansions into north-central regions during interglacial periods. Populations with indehiscent sporangium can carry private haplotypes and are inclined to maintain genetic homogeneity. One group with indehiscent sporangia most likely survived in situ on the QTP during glaciations. CONCLUSIONS/SIGNIFICANCE: This study for the first time sheds light on the response of alpine ferns in the QTP and HHM to the Quaternary climatic oscillations.