First record of a natural hybrid Neotinea × dietrichiana (Orchidaceae) in Serbia

Abstract. Neotinea × dietrichiana (Orchidaceae), a natural hybrid between Neotinea tridentata and N. ustulata, has been found on the southwestern slopes of Mt Maljen (Western Serbia) for the first time in Serbia, representing its most continental record in the Balkans. Morphological and distribution data, as well as the ecological preferences of N. × dietrichiana are provided. The hybrid grows between 490 m and 510 m a.s.l., on serpentine substrate, as a member of xero-mesophilous steppe-like meadows. Hybrid specimens have been recorded at the sites where the two parental species grow in sympatry, and mostly where the population size of N. tridentata is larger than the population size of N. ustulata

Identifying important areas for orchid conservation in Crete

Crete is especially rich in orchids and their distribution is well known and documented by many floristic accounts. This information, however, is yet to be used to set conservation plans and priorities. We used MaxEnt incorporating both published and unpublished distribution data together with environmental variables to predict the potential distribution of orchids on Crete. The resulting probabilistic maps of species occurrence were used to identify the important areas for orchid conservation on the island. Sites prioritization was performed by applying a species weighting scheme, which was based on species niche breadth. The existence of ecological patterns determining site prioritization was determined using a regression tree analysis based on environmental variables and scores derived from Zonation analysis. The high importance sites were found on Mts Thripti, Ida and Lefka Ori, as well as at low altitude areas east of Heraklion and at the easternmost part of the island. Most of the variation in the site scores was explained by geological substrate, latitude and altitude. Based on the regression tree analysis, sites with the highest scores were at medium and high altitude areas, which are located at the interior of the island. These areas have soils mainly derived from limestones, ophiolites and deposits of calcareous rocks. The lack of a significant effect of vegetation type in explaining the distribution of high importance areas highlights the need for the establishment of micro-reserves for the conservation of orchids in Crete. Finally, endangered orchid species in need of specific conservation actions are indicated

Distribution of Orchids with Different Rooting Systems in the Czech Republic

Understanding diversity patterns along altitudinal gradients and the effect of global change on abundance, distribution patterns and species survival are of the most discussed topics in biodiversity research. Here, we determined the associations of orchid species richness and the degree of their specialization to specific environmental conditions (expressed by species specialization index) with altitude in six floristic areas in the Czech Republic. We distinguished three basic trends in these relationships: linear, parabolic and cubic. We then determined whether these trends differ between three orchid groups classified by their rooting systems: rhizomatous, intermediate and tuberous. We used distributional data on 69 species and subspecies of terrestrial orchids recorded in the Czech Republic and interpolated them at 100-m intervals along an altitudinal gradient in each floristic area. The trends in both species richness and mean species specialization index differed between the six floristic areas within each of the three orchid groups studied. These patterns are probably strongly influenced by the orography of the country and the distribution of different habitats in the six floristic areas in the Czech Republic. We also found that the most widely distributed orchid group in the Czech Republic are the rhizomatous orchids, followed by intermediate and tuberous ones

Elevational gradient of vascular plant species richness and endemism in Crete--the effect of post-isolation mountain uplift on a continental island system.

Understanding diversity patterns along environmental gradients and their underlying mechanisms is a major topic in current biodiversity research. In this study, we investigate for the first time elevational patterns of vascular plant species richness and endemism on a long-isolated continental island (Crete) that has experienced extensive post-isolation mountain uplift. We used all available data on distribution and elevational ranges of the Cretan plants to interpolate their presence between minimum and maximum elevations in 100-m elevational intervals, along the entire elevational gradient of Crete (0-2400 m). We evaluate the influence of elevation, area, mid-domain effect, elevational Rapoport effect and the post-isolation mountain uplift on plant species richness and endemism elevational patterns. Furthermore, we test the influence of the island condition and the post-isolation mountain uplift to the elevational range sizes of the Cretan plants, using the Peloponnese as a continental control area. Total species richness monotonically decreases with increasing elevation, while endemic species richness has a unimodal response to elevation showing a peak at mid-elevation intervals. Area alone explains a significant amount of variation in species richness along the elevational gradient. Mid-domain effect is not the underlying mechanism of the elevational gradient of plant species richness in Crete, and Rapoport's rule only partly explains the observed patterns. Our results are largely congruent with the post-isolation uplift of the Cretan mountains and their colonization mainly by the available lowland vascular plant species, as high-elevation specialists are almost lacking from the Cretan flora. The increase in the proportion of Cretan endemics with increasing elevation can only be regarded as a result of diversification processes towards Cretan mountains (especially mid-elevation areas), supported by elevation-driven ecological isolation. Cretan plants have experienced elevational range expansion compared to the continental control area, as a result of ecological release triggered by increased species impoverishment with increasing elevation

The effects of presence/absence vs. continuous suitability data on reserve selection

Species distribution models are widely applied for generating the appropriate data for designing networks of reserve systems. The aim of the present study is to compare the use of presence/absence and continuous suitability data, derived from species distribution models, in reserve selection, and to detect any systematic trends in the reserve networks produced on the basis of these two types of data. The MAXENT model was applied to predict orchids’ potential distribution in east Macedonia (northeast Greece). One presence/absence and one with suitability values data set was made and used in the ZONATION decision support tool in order to prioritize the cells of the study area for inclusion in a reserve network. In the selection procedure, species weighting has been applied by using the species specialization index. Results show that the presence/absence data set favors the selection of cells with more extreme climatic conditions and more distant from the mean habitat of the study area. Furthermore, the continuous suitability data set provides higher suitability values for the specialist taxa in comparison with the presence/absence data set, while the opposite is happening for the generalist taxa. The present study reveals that the suitability data outperform the presence/absence data in reserve selection because: (a) they better represent the average environmental conditions of the study area in the selected networks; (b) they ensure higher suitability values for the specialist species, which are more prone to extinction in the future; and (c) they take full advantage of species weighting according to their habitat specificity

Discriminación fitosociológica y ecológica de las comunidades de ciprés (Cupressus sempervirens) en Creta (Grecia) mediante análisis polínico

[EN] Sixty modern surface samples collected from mosses in different cypress forest communities (Cupressus sempervirens L.) on the island of Crete (Greece) were analysed for their pollen content. The samples were taken from six different cypress phytosociological associations between 23 and 1600 m asl, and fall within distinct rainfall and temperature regimes. The aims of this paper are to provide new data on the modern pollen rain from the Aegean islands, and to perform these data using multivariate statistics (hierarchical cluster analysis and canonical correspondence analysis) and pollen percentages. The discrimination of pollen assemblages corresponds to a large extent to the floristic differentiation of Cupressus sempervirens forest vegetation and indicates the existence of three new associations[ES] Sesenta muestras de lluvia polínica actual recolectadas en cepellones de musgos, procedentes de distintas comunidades de ciprés (Cupressus sempervirens L.) en la isla de Creta (Grecia), fueron analizadas palinológicamente. Las muestras proceden de seis asociaciones fitosociológicas dominadas por el ciprés entre 23 y 1600 m asl, bajo regímenes de precipitación y temperatura diferentes. El objetivo de este trabajo es prover datos novedosos acerca de la lluvia polínica actual en las islas del Egeo, así como tratar éstos mediante análisis multivariantes (análisis de cluster jerárquico y análisis de correspondencias canónicas) y a partir de sus porcentajes polínicos. La discriminación de los espectros polínicos corresponde en gran medida a la diferenciación florística de la vegetación de los bosques de Cupressus sempervirens e indica la existencia de tres nuevas asociacionesThis study is part of the international PALEOMEX-INEE Research Program, itself a component of the Mediterranean Integrated Studies at Regional and Local Scales (MISTRALS) of the CNRS, France

Data on the elevational range size of the vascular plants.

<p>(A) average elevational range of total species, (B) log-transformed total number of species with a very narrow elevational range (100–200 m), (C) average elevational range of Cretan endemics (circles) and Peloponnesian endemics (squares) and (D) proportion of lowland species in the upper one-third of the elevational gradient for Cretan subendemics (triangles), Cretan endemics (circles) and Peloponnesian endemics (squares). Trend lines were set by simple regressions (A, B, C) and generalized linear models (D). (* p<0.001).</p

Topographic map of Crete with the three main mountain massifs.

<p>Topographic map of Crete with the three main mountain massifs.</p

Modern Pollen\textendashVegetation Relationships along an Altitudinal Transect in the Lefka Ori Massif (Western Crete, Greece)

The paucity of modern pollen rain data from the Aegean islands is a significant barrier to understand the lateQuaternary vegetation history of this globally important south-eastern Mediterranean region. This paper pre-sents the study of 30 modern pollen and non-pollen palynomorph assemblages carried out along an altitudinalgradient from 0 to 2453 m in the Lefka Ori massif (eastern Crete, Greece). This research aimed to analyze lowlandand highland pollen and NPP in relation to vegetation, climate and grazing, and to evaluate the regional and localsignificance of modern pollen deposition. Canonical correspondence analysis showed that altitude, precipitationof the driest month, annual mean temperature, precipitation seasonality and grazing are the most significantvariables to explain pollen and NPP variability in this area. It also made it possible to characterize pollen andNPP indicators of types of highland and lowland vegetation and grazing pressure. Results obtained corroboratethe significant role of coprophilous fungi as local indicators of herbivores in south-eastern Mediterranean mountain areas and suggest the local presence of domestic animals.This study is part of the international PALEOMEX-INEE Research Program, itself a component of the Mediterranean Integrated Studies at Regional and Local Scales (MISTRALS) of the CNRSPeer Reviewe

Predicted of the null model simulation and observed values of species richness concerning mid-domain effect.

<p>The comparisons concern to (A) vascular plant species richness and (B) Single Island Endemics.</p