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This paper aims to shed light on distribution patterns and the relationship between species diversity and environmental heterogeneity of 17 Edraianthus taxa. We examined present and past distributions (Last Glacial Maximum) by applying ecological niche modelling. The environmental space occupied by the taxa was analysed using niche comparison methods. The results support the idea that the central and southern Dinaric Alps represent a centre of diversity and endemism in the western Balkan Peninsula. Diversity in Edraianthus is best explained by topographic (slope) and bioclimatic predictors (maximum temperature of warmest month, precipitation seasonality, precipitation of warmest quarter, precipitation of coldest quarter), suggesting that mountain areas with the most diversified relief have higher diversity. Niche modelling results suggest considerable range dynamics during the climatically unstable Quaternary. Thermophilic and lowland taxa responded with longitudinal shifts to ecologically suitable areas farther south, whereas high-mountain taxa responded mainly with elevational shifts. The greatest niche similarity is found among phylogenetically closely related taxa and among ecologically similar and often sympatric taxa. The least similarity was observed in species with marked differences in habitat elevation and in more geographically isolated species. Our results suggest that the extent of range and niche overlap varied among some taxa throughout their evolutionary history, which may have led to diversification at both allopatric and sympatric levels. The correlation between the genetic diversity of the most widespread taxon and the richness of taxa could be a consequence of past and present contacts. On the other hand, alternate periods of isolation may have favoured the emergence of taxa that are reproductively isolated and ecologically specialized. [ABSTRACT FROM AUTHOR] more...

The high-biodiversity phenomenon of the Balkan Peninsula is a result of the past and present topographic, climatic and geological conditions, as well as human impact. The Dinaric Alps, as a part of the Balkan Peninsula, harbour a high number of endemic species, some of them comprising a small number of populations, which are often endangered. We investigated spatial distribution, community composition, site ecology, genetic diversity and conservation of Degenia velebitica, a stenoendemic species of the north-western Dinaric Alps. Our results showed that D. velebitica is nowadays restricted to three localities with the area of occupancy of 48,560 m2, harbouring approximately 37,000 individuals. Degenia velebitica stands are differentiated into three well-characterized, floristically homogenous syntaxa, very distinct from the surrounding vegetation, suggesting their azonal occurrence and restriction to spatially highly fragmented microsites exposed to stormy winds. Spatial distances of populations, differences in D. velebitica community composition and site ecology are mirrored in genetic variation patterns of the populations, such as high-frequency down-weighted marker values in the north-western populations and high gene diversity in the south-eastern group of populations. The fact that we could not find a single D. velebitica individual at the locus classicus indicates the existence of the ever-growing fragmentation. The analyses of genetic structure using AFLP data recognized two main genetic groups of populations as evolutionary significant units that should be considered when planning protection measures. According to our IUCN Red List reassessment, D. velebitica should be treated as a critically endangered species that requires immediate conservation actions. [ABSTRACT FROM AUTHOR] more...

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We studied the phytosociology, ecology and biogeography of the Dinaric fir-beech stands (Omphalodo-Fagetum) in the Trnovski gozd plateau, at the north-western part of the Illyrian floral province. We identified and confirmed two geographical variants (var. geogr. Saxifraga cuneifolia - central and western part of the plateau, and var. geogr. Calamintha grandiflora - eastern part of the plateau), and 10 floristically and ecologically well differentiated subassociations (-rhododendretosum hirsuti,-saxifragetosum cuneifoliae, -adenostyletosum glabrae, -festucetosum altissimae, -calamagrostietosum arundinaceae, -stellarietosum montanae, -seslerietosum autumnalis, -calamagrostietosum variae, -sambucetosum nigrae and -asaretosum europei). The most frequent stands bellong to the subassociation -festucetosum altissimae and -calamagrostietosum arundinaceae, which, in terms of site ecology and floristic composition, represent the central forest types in the research area. They are floristically impoverished and lack majority of association's characteristic species which is in line with the biogeographic peculiarites of the research area. [ABSTRACT FROM AUTHOR] more...

We investigated Quaternary range dynamics of two closely related but ecologically divergent species (cold-tolerant Edraianthus serpyllifolius and thermophilic Edraianthus tenuifolius) with overlapping distribution ranges endemic to the western Balkan Peninsula, an important yet understudied Pleistocene refugium. Our aims were: to test predictions of the 'refugia-within-refugia' model of strong genetic subdivisions due to population isolation in separate refugia; to explore whether two ecologically divergent species reacted differently to Pleistocene climatic fluctuations; and to test predictions of the displacement refugia model of stronger differentiation among populations in the thermophilic E. tenuifolius compared with the cold-tolerant E. serpyllifolius. The western Balkan Peninsula. We gathered amplified fragment-length polymorphism (AFLP) data and plastid DNA sequences from two to five individuals from 10 populations of E. serpyllifolius and 22 populations of E. tenuifolius, spanning their entire respective distribution areas. AFLP data were analysed using a Bayesian clustering approach and a distance-based network approach. Plastid sequences were used to depict relationships among haplotypes in a statistical parsimony network, and to obtain age estimates in a Bayesian framework. In E. serpyllifolius, both AFLP and plastid sequence data showed clear geographic structure. Western populations showed high AFLP diversity and a high number of rare fragments. In E. tenuifolius, both markers congruently identified a major phylogeographic split along the lower Neretva valley in central Dalmatia. The most distinct and earliest diverging chloroplast DNA (cpDNA) haplotypes were found further south in the south-easternmost populations. North-western populations, identified as a separate cluster by Bayesian clustering, were characterized by low genetic diversity and a low number of rare AFLP markers. Clear evidence for multiple Pleistocene refugia is found not only in the high-elevation E. serpyllifolius, but also in the lowland E. tenuifolius, despite the lack of obvious dispersal barriers, in line with the refugia-within-refugia model. Genealogical relationships and genetic diversity patterns support the hypothesis that cold-adapted E. serpyllifolius responded to climatic oscillations mostly by elevational range shifts, whereas thermophilic E. tenuifolius did so mainly by latitudinal range shifts, with different phases (and probably extents) of range expansion. In contrast to the displacement refugia hypothesis, the two elevationally differentiated species do not differ in their genetic diversity. [ABSTRACT FROM AUTHOR] more...

Edraianthus sutjeskae R. Lakušić, originaly described in 1974, was an invalidly published name because in its type citation the collector's name and collection date were omitted. Hereby we validate the name by indicating the holotype kept at the Natural Museum of Bosnia and Herzegovina (SARA). [ABSTRACT FROM AUTHOR] more...