Numerical analyses of distributions of Iberian and Balearic endemic monocotyledons

Chorological information concerning 182 taxa of monocotyledons endemic to the Iberian Peninsula and Balearic Islands was compiled and related to the 100×100 km, 50×50 km and 10×10 km UTM grids. Distributions were analysed using multivariate methods (two-way indicator species analysis and detrended correspondence analysis) for each scale. Comparison of results allows recognition of several floristic elements and sectors (i.e. Balearic, Murcian-Almerian, south western) common to all three scales, whereas other regions are assigned to different sectors depending on the grid size considered. As a consequence of the increase in detail, characteristics such as number of sectors, the outline of boundaries and continuity or fragmentation of the areas also change. These factors are discussed.     

Spatial and environmental determinants of vascular plant species richness distribution in the Iberian Peninsula and Balearic Islands

Using an exhaustive data compilation, Iberian vascular plant species richness in 50 times 50 UTM grid cells was regressed against 24 explanatory variables (spatial, geographical, topographical, geological, climatic, land use and environmental diversity variables) using Generalized Linear Models and partial regression analysis in order to ascertain the relative contribution of primary, heterogeneous and spatially structured variables. The species richness variation accounted for by these variables is reasonably high (65% of total deviance). Little less than half of this variation is accounted for spatially structured variables. A purely spatial component of variation is hardly significant. The most significant variables are those related to altitude, and particularly maximum altitude, whose cubic response reflects the occurrence of the maximum number of species at the highest altitudes. This result highlighted the importance of Iberian mountains as hotspots of diversity and the relevance of large and small scale historical factors in contemporary plant distribution patterns. Climatic or energy-related variables contributed little, whereas geological (calcareous and acid rocks) and, to a lesser extent, environmental heterogeneity variables (land use diversity and altitude range) seem to be more important.     

Karyological observations on plant taxa endemic to the Balearic Islands

Mitotic chromosome numbers are reported from 35 vascular plant taxa endemic to the Balearic Islands that are poorly known cytogenetically. The chromosome numbers of Chaenorhinum rodriguezii (2 n  = 14), Coristospermum huteri (2 n  = 22), Carduus ibicensis (2 n  = 26), Filago petro-ianii (2 n  = 26), Ononis crispa ssp. zschackei (2 n  = 30), and Ophrys bertolonii ssp. balearica (2 n  = 36) were determined for the first time. New chromosome numbers are reported in Pimpinella bicknellii (2 n  = 22), Calamintha rouyana (2 n  = 46), Vicia bifoliolata (2 n  = 14), and Teucrium asiaticum (2 n  = 30). A new diploid cytotype (2 n  = 16) was found in Ranunculus paludosus ssp. barceloi , which is restricted to populations from the western Balearics (Eivissa and Formentera), whereas tetraploid plants are known from the eastern Balearics (Mallorca). It is suggested that the tetraploid cytotype arose from the diploid cytotype through autopolyploidy. The idiograms of Coristospermum huteri , Pastinaca lucida , Pimpinella bicknellii , Carduus ibicensis , Helianthemum scopulicolum , Helichrysum crassifolium , Vicia bifoliolata , p aeonia cambessedesii , Helleborus lividus , Ranunculus paludosus ssp. barceloi , and Linaria aeruginea ssp. pruinosa are determined for the first time.  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 153 , 463–476.     

Spatial patterns of an endemic Mediterranean palm recolonizing old fields

Throughout Europe, increased levels of land abandonment lead to (re)colonization of old lands by forests and shrublands. Very little is known about the spatial pattern of plants recolonizing such old fields. We mapped in two 21–22‐ha plots, located in the Doñana National Park (Spain), all adult individuals of the endozoochorous dwarf palm Chamaerops humilis L . and determined their sex and sizes. We used techniques of spatial point pattern analysis (SPPA) to precisely quantify the spatial structure of these C. humilis populations. The objective was to identify potential processes generating the patterns and their likely consequences on palm reproductive success. We used (1) Thomas point process models to describe the clustering of the populations, (2) random labeling to test the sexual spatial segregation, and (3) mark correlation functions to assess spatial structure in plant sizes. Plants in both plots showed two critical scales of clustering, with small clusters of a radius of 2.8–4 m nested within large clusters with 38–44 m radius. Additional to the clustered individuals, 11% and 27% of all C. humilis individuals belonged to a random pattern that was independently superimposed to the clustered pattern. The complex spatial pattern of C. humilis could be explained by the effect of different seed‐dispersers and predators' behavior and their relative abundances. Plant sexes had no spatial segregation. Plant sizes showed a spatial aggregation inside the clusters, with a decreasing correlation with distance. Clustering of C. humilis is strongly reliant on its seed dispersers and stressful environmental conditions. However, it seems that the spatial patterns and dispersal strategies of the dwarf palm make it a successful plant for new habitat colonization. Our results provide new information on the colonization ability of C. humilis and can help to develop management strategies to recover plant populations.     

Anisian floras from the NE Iberian Peninsula and Balearic Islands: A synthesis

This paper focuses on the diversity and palaeontological significance of the Anisian floral record in the Triassic of the northeastern Iberian Peninsula. A summary of published information is followed by new records from macrofloral localities at Rodanas (Aragonese Branch of the Iberian Range) and at Maya del Baztán (Basque-Cantabrian Domain, Pyrenees). Both of these new localities also yielded three Anisian microfloral assemblages. These records provide new evidence of Anisian (basal Middle Triassic) floras in Spain. They are found to be somewhat similar to the classical flora of the Grès à Voltzia Formation (Upper Buntsandstein) of the northern Vosges in north-eastern France, of whose age has been shown to be early Anisian.     

Chromosome numbers in plant taxa endemic to the Balearic Islands

Mitotic chromosome numbers are reported from 20 vascular plant taxa that are endemic to the Balearic Islands and poorly known cytogenetically. The chromosome numbers of Arenaria grandiflora L. ssp. glabrescens (Willk.) G. López & Nieto Feliner (2 n  = 44), Dianthus rupicola Viv. ssp. bocchoriana L. Llorens & Gradaille (2 n  = 30), Solenopsis minuta (L.) C. Presl. ssp. balearica (E. Wimm.) Meikle (2 n  = 28), Romulea asumptionis Font Quer & Garcías Font (2 n  = 56), Scutellaria balearica Barceló (2 n  = 22) and Galium balearicum Briq. (2 n  = 22) have been determined for the first time. A new chromosome number was found in two populations of Helictotrichon crassifolium (Font Quer) Holub (2 n  =  c. 98) suggesting that this species is a high polyploid (14 x ), in contrast to an earlier report of a lower chromosome count (2 n  = 12 x  = 84). Cytogenetic observations suggest that Naufraga balearica Constance & Cannon has a diploid chromosome complement of 2 n  = 20, with 0–2 accessory chromosomes. The banded karyotype (chromomycin A₃) of Crepis triasii (Cambess.) Fries was determined for individuals belonging to eight populations from three islands. Two chromomycin A₃-positive regions were recorded in the diploid complement. These are present on the telomeric regions of the shortest subtelocentric chromosomes. This species is karyologically stable in chromosome number, karyotype and fluorochrome-banding pattern among populations from separate islands.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 148 , 219–228.     

New chromosome numbers for plant taxa endemic to the Balearic Islands

Mitotic chromosome numbers are reported from 25 vascular plant taxa, endemic to the Balearic Islands that are poorly known cytogenetically. The chromosome numbers ofAnthyllis vulneraria subsp.balearica (2n=12),Cymbalaria fragilis (2n=56), andPolygonum romanum subsp.balearicum (2n=40) were determined for the first time. A new chromosome number was found in several populations ofAnthyllis hystrix (2n=70) suggesting that this species is decaploid, in contrast to an earlier work reporting a higher ploidy level (2n=12x=84). The new chromosome number 2n=32 was reported inHypericum hircinum subsp.cambessedesii. It is suggested that the previous count (2n=40) could be explained by the presence of anomalous pentaploid cells in some tissues, contrating with the presence of a regular tetraploid complement (2n=32). Cytogenetic observations suggest thatSibthorpia africana has a diploid chromosome complement of 2n=18, with 0–2 accessory chromosomes. Accessory chromosomes are also reported forPhlomis italica, being the first record of B chromosomes in this genus. Chromosomal instability was found inGalium crespianum andG. friedichii species, with three numbers 2n=44, 55 and 66. Two cytotypes differing in ploidy level were documented within single plants. It is suggested that both species share a regular complement of 2n=44 and that the past hybridization events and formation of regenerating roots from the typical rootstock ofG. crespianum andG. friedrichii could be involved in the genesis of chromosome variants through partial endopolyploidy and concomitant somatic segregation.     

Climate change and the future of California's endemic flora

The flora of California, a global biodiversity hotspot, includes 2387 endemic plant taxa. With anticipated climate change, we project that up to 66% will experience >80% reductions in range size within a century. These results are comparable with other studies of fewer species or just samples of a region's endemics. Projected reductions depend on the magnitude of future emissions and on the ability of species to disperse from their current locations. California's varied terrain could cause species to move in very different directions, breaking up present-day floras. However, our projections also identify regions where species undergoing severe range reductions may persist. Protecting these potential future refugia and facilitating species dispersal will be essential to maintain biodiversity in the face of climate change.     

Phytogeographical patterns of genera of endemic flora in relation to latitudinal and climatic gradients in China

This paper aims at detecting the relationships between phytogeographical patterns of genera of Chinese endemic seed plants and latitude or climatic factors. The landmass of China was divided into four latitudinal zones, each of c. 8°. Based on a total of 1664 indigenous genera of Chinese endemic seed plants which were grouped into fifteen geographical elements, belonging to three major categories (cosmopolitan, tropical and temperate) and which were absent or present in 28 provinces in China, we analyzed the phytogeographical patterns of genera of Chinese endemic seed plants and detected the relationships between them and main climatic factors. Our results showed that the proportion of tropical genera decreases with the increase in latitude; the proportion of temperate genera increases with the increase in latitude; and the proportion of cosmopolitan genera increased gradually increased gradually with latitude. There are a slow decrease in the proportion of tropical genera and slow increase in the proportion of temperate genera at latitudes 35°–40°. Alternatively, the tropical genera and the temperate genera have the same proportion at latitude c. 25°. These changes and issues about the different genera also appeared in main climate factors. In general, the genera present in a more northerly flora are a subset of the genera present in a more southerly flora. In summary, the large-scale patterns of phytogeography of endemic flora in China are strongly related to latitude, which covary with several climatic variables such as temperature.     

The endemic bovids from Sardinia and the Balearic Islands: State of the art

Bovids are not so common in endemic insular faunas and are mainly recorded in Southeast Asia, Japan and some Mediterranean islands. In the Western Mediterranean, endemic bovids have been recorded during the late Miocene in the Tusco-Sardinian palaeobioprovince (Baccinello-Cinigiano basin, South Tuscany, and Fiume Santo, north-western Sardinia). In the latest Neogene and Quaternary, bovids showing highly endemic features were restricted to the Balearic Islands and Sardinia, while Bovini only slightly reduced in size were present on Pianosa, Malta and Sicily. On Sardinia, the richest bovid sample comes from Monte Tuttavista (Orosei), where at least three species have been identified: Asoletragus genthry, Nesogoral aff. N. melonii, and Nesogoral sp. 2. On Mallorca (Balearic Islands) six chronospecies belonging to the Myotragus endemic phylogenetic lineage have been described, spreading in age from the Early Pliocene to the Holocene. For decades, a close phylogenetic relationship between Nesogoral and Myotragus has been widely accepted by scholars. Morphological and biometrical differences shown by Balearic and Sardinian bovids have generally been regarded as the result of the evolution into two different island ecological systems, characterized by different inter and intra-guild selection pressures. Indeed, the more diversified environment of Sardinia, as well as the presence of other large mammals (similar-sized competitors belonging to the same guild and a running predator), increased the interspecific competition, forcing Sardinian bovids to exploit different resources and to occupy different niches, while Myotragus exploited under a monopoly regime the supply of resources available for large herbivores on the Eastern Balearic Islands. Nonetheless, new data suggest that Nesogoral and Myotragus possibly originated from different taxa.     

Ecological characteristics of the flora of the Northwest Iberian Peninsula

This study reports an investigation of relationships between environmental variables (electrical conductivity of groundwater, soil redox potential, water-table depth, and high-tide flooding depth) on vegetation zonation in a salt-marsh system on the coast of northwest Spain. Discriminant analysis indicated that conductivity (a measure of salinity) and redox potential are correlated with vegetation type within the study area. Conductivity declines with increasing altitude and distance from the sea, whereas redox potential does not vary along well-defined large-scale gradients. Soils with the most strongly oxidizing conditions (i.e. moderate salinity, with Eh greater than 200 mV and thus subtoxic levels of Mn²⁺, Fe²⁺ and S^2-) are occupied by the Halimione portulacoides community. Communities dominated by Juncus maritimus, and Phragmites australis reedbeds, occur at more strongly reducing sites (Eh between 100 and 200 mV, with possibly toxic levels of Mn²⁺ but not of Fe²⁺); the presence of these communities may thus be limited by Fe²⁺ toxicity. The most strongly reducing sites (with Eh low enough for the reduction of Fe³⁺ to Fe²⁺) are occupied by Spartina maritima and Scirpus maritimus communities. These communities appear to be tolerant of Fe²⁺, and even of low concentrations of S^2-.     

Karyology of Limonium (Plumbaginaceae) species from the Balearic Islands and the western Iberian Peninsula

Somatic chromosome numbers, conventional karyotype features and idiograms are reported for 27 Limonium species inhabiting the Western Mediterranean basin (Iberian Peninsula and the Balearic Islands). The chromosome numbers of Limonium barceloi (2 n  = 36), L. ejulabilis (2 n  = 24), L. inexpectans (2 n  = 26), L. interjectum (2 n  = 24), and L. scopulorum (2 n  = 25) were determined for the first time. In addition, new aneuploid and/or polyploid cytotypes are reported in L. alcudianum (2 n  = 26), L. bonafei (2 n  = 26), L. camposanum (2 n  = 26) , L. companyonis (2 n  = 26), L. dufourii (2 n  = 26), L. geronense (2 n  = 36), L. marisolii (2n = 54), L. migjornense (2 n  = 50), and L. pseudodictyocladon (2 n  = 16). A group of polyploid species showed karyotypes comprising homologous chromosomes in groups of three ( L. antonii-llorensii, L. ejulabilis, L. interjectum, L. virgatum, and L. wiedmanii ) , four ( L. geronense ), or six ( L. marisolii ), which suggests an autopolyploid origin. Other polyploid species were characterized by the presence of two different chromosome sets ( x  = 8 and x  = 9) in the genome. The species L. alcudianum , L . bonafei , L. camposanum , L. companyonis , L. dufourii , L. gibertii , L. girardianum , L. inexpectans , L. leonardi-llorensii , L. magallufianum , L. migjornense , L. minoricense , and L. scopulorum showed various combinations of paired and unpaired x  = 8 and x  = 9 chromosome sets, suggesting that they are allopolyploids. © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 155 , 257–272.     

Rarity and threat relationships in the conservation planning of Iberian flora

We analysed the threatened flora of Iberia (including the Balearic Islands) in order to define and explain factors related to levels of rarity and threat. Conservation measures were derived from the relationships observed. We used a random sample of 59 narrowly distributed plant species from the pool (588 species) of potentially endangered flora. Twelve variables were used to classify species into groups based on a multivariate technique: non-parametric principal component analysis. Our results do not indicate a single management model driven by a single mechanism of rarity. Four classes of rare plants were produced from the statistical algorithm: agamospermic species, plants associated with water, endemics, and range-margin (geographical-limit) plants. Some specific strategies for each of these groups are proposed, allowing further discussion and assessment. The overall pattern in conservation practice of threatened Iberian plants seems to be defined by three of the variables in use: ecological specificity, geographical rarity and rate of threat. None of the biological variables in the sample show particularly strong trends in the data.     

Diel variation in movement patterns and habitat use by the Iberian endemic Cabrera vole: Implications for conservation and monitoring

Understanding variations in animal movement and habitat selection behaviour over fine spatial and temporal scales remains a particularly challenging goal in ecology and conservation. Here we document for the first time the diel variations in movement patterns and habitat use by wild-ranging Cabrera voles in fragmented Mediterranean farmland, based on radiotracking data (2006–2008) of 25 adult individuals occupying stable home-ranges in vegetation mosaics dominated by wet grasses and shrubs. Results indicated that the proportion of time animals spent moving, the distance moved, and the selection strength of main vegetation types were closely linked behavioural traits, which varied considerably across different periods of the 24-h cycle. In general, voles moved more frequently and over larger distances during daytime (between 06 h15–22 h00), which was when wet grasses were also used more intensively. These patterns were generally consistent across seasons, though during the dry season there was some tendency for a decrease in movement activity during the hottest hours of the day (between 10 h15–14 h00), with peaks around crepuscular hours (06 h15–10 h00 and 18 h15–22 h00). Overall, our study provides evidence that Cabrera voles may show notable shifts in habitat use and movement patterns on a finer scale than previously considered. This supports the idea that knowledge of the diel variations in species movement-habitat relationships should strongly contribute to improving local habitat management, as well as effective sampling and monitoring programs targeting the species.     

Elevational patterns in the vascular flora of a highly diverse region in southern Mexico

We examined general and family-specific patterns of vascular plant richness along a large elevational gradient (0?C3,670?m a.s.l.), assessed the continuity of these patterns and analysed their potential underlying causes in a high diversity region of the Sierra Madre del Sur, Oaxaca, Mexico. We used a vascular plant database constructed previously. The gradient was divided into 18 200-m elevation belts. To examine elevational patterns of richness, we used both observed and estimated (interpolated) species richness, as well as genus and family observed richness, for each belt. A generalised linear model (GLM) was used to assess the effect of altitude on area-corrected species richness (standard area?=?100?km²), and a numerical classification of the elevational belts based on species richness was performed. Overall, richness at the three taxonomic levels decreased with elevation, but some individual families departed from this pattern. A sharp drop in species richness was observed at 1,800?m, and the dendrogram separated two elevational floristic groups at this elevation. The GLM revealed a significant negative effect of elevation on species richness. Despite this overall decreasing pattern for vascular plants along this extensive gradient, an examination of some family-specific patterns revealed the existence of other elevation?Cdiversity relationships, indicating taxon-specific responses to elevation. The most noticeable discontinuity in species richness, at ca. 1,800?m, is likely related to a critical temperature isocline.     

Sexual reproduction in someScrophularia species (Scrophulariaceae) from the Iberian Peninsula and the Balearic Islands

The reproductive biology of someScrophularia species in the Iberian Peninsula and Balearic Islands has been studied. Levels of fruit-set in bagged and unbagged inflorescences, the production of seeds/capsule, the effectiveness of seed-set following cross-pollination in the genus and the pollen/ovule ratios have been analyzed.Some observations on floral and reproductive biology in some species ofScrophularia from the Iberian Peninsula and Balearic Islands. II. For first part seeOrtega Olivencia & Devesa 1993.