Phylogenetic reconstruction of key traits in the evolution of ivies (Hedera L.)

The Mediterranean harbours the highest number of Hedera (Araliaceae) species, lineages, ploidy levels, and trichome morphologies of any area where the genus occurs. Previous molecular and cytogenetic studies identified two main centres of diversity for Hedera (Araliaceae), the eastern and western parts of the Mediterranean region. An explicit analysis of key traits was performed to investigate geographical patterns and ancestral character states of ivy lineages. Interestingly, the greatest diversity of Hedera was found in the western Mediterranean, including the three species of Macaronesia (H. azorica in the Azores, H. maderensis in Madeira and H. canariensis in the Canary Islands). Phylogenetic and phylogeographical analyses of the nrITS and plastid trnT-L sequences revealed multiple connections between the Mediterranean region and Asia, and suggest recurrent colonization between these two areas. Reconstruction of three important characters long used to distinguish members of the genus (trichome types, ploidy levels, and geographical areas) suggests that a diploid species with scale-like trichomes from the Mediterranean basin was the most recent common ancestor of the extant species of Hedera.     

Chloroplast sequences reveal a diversity gradient in the Mediterranean Ruppia cirrhosa species complex

Two subcosmopolitan species Ruppia maritima and Ruppia cirrhosa are recognized throughout Europe, whereas Ruppia drepanensis is endemic to SW Europe. We aimed at characterizing the geographic structure of the chloroplast DNA haplotype diversity of 56 Ruppia populations across the European part of the Mediterranean. On the basis of five cpDNA markers (total length of 2300 bp) 16 haplotypes were obtained for 1546 individuals. Three populations of R. maritima showed a single haplotype and differed in five insertions/deletions and 16 substitutions from a highly variable R. cirrhosa species complex, which included R. drepanensis. The haplotype diversity of this species complex was much higher in the western Mediterranean basin than in the eastern basin. Analysis of molecular variance (AMOVA) showed significant differentiation of R. cirrhosa between the two basins and also within the western Mediterranean thereby suggesting the latter as an important centre of Ruppia diversity. An isolation-by-distance (IBD) pattern was stronger between the West-East basin populations than within basins. A PCO analysis of the western basin populations indicated a diversity gradient with those of Sardinia as polymorph intermediates. The low diversity within the eastern basin suggests that the observed gradient could be hypothesized as a historical dispersal of only a limited number of haplotypes from west to east.     

Acaulon fontiquerianum Casas et Sérgio (Musci,Pottiaceae) new to Sardinia (Italy)

Acaulon fontiquerianum Casas et Sérgio (Pottiaceae) was found in the course of bryological research conducted in a coastal area of southeastern Sardinia. The ecological characteristics of the site and the current distribution of the species in the Mediterranean basin are reported.     

A two-gene phylogeny shows the lichen genus Niebla (Lecanorales) is endemic to the New World and does not occur in Macaronesia nor in the Mediterranean basin

The generic segregates of the widespread fruticose genus Ramalina (mostly based on empirical data on morphology, cortex anatomy and secondary metabolites) are studied using maximum parsimony, maximum likelihood and Bayesian analyses of nuclear LSU and ITS sequences. The species examined include the three species aggregates within Niebla from the western coasts of North America, all species except one assumed to belong to the same genus from Macaronesia and the Mediterranean basin, the type species of Dievernia and Ramalina, and representatives of the genus Fistulariella. The genus Niebla is strongly supported when restricted to species from the New World, and all species referred to it from Macaronesia and the Mediterranean basin belong to Ramalina (R. bourgeana, R. crispatula, R. cupularis, R. hamulosa, R. portosantana, R. rosacea, R. subwebbiana and R. webbii). No support is found for the genera Dievernia and Fistulariella. The internal topology of the large genus Ramalina is unresolved and needs further studies.     

Population Structure and Dispersal Patterns within and between Atlantic and Mediterranean Populations of a Large-Range Pelagic Seabird

Dispersal is critically linked to the demographic and evolutionary trajectories of populations, but in most seabird species it may be difficult to estimate. Using molecular tools, we explored population structure and the spatial dispersal pattern of a highly pelagic but philopatric seabird, the Cory''s shearwater Calonectris diomedea. Microsatellite fragments were analysed from samples collected across almost the entire breeding range of the species. To help disentangle the taxonomic status of the two subspecies described, the Atlantic form C. d. borealis and the Mediterranean form C. d. diomedea, we analysed genetic divergence between subspecies and quantified both historical and recent migration rates between the Mediterranean and Atlantic basins. We also searched for evidence of isolation by distance (IBD) and addressed spatial patterns of gene flow. We found a low genetic structure in the Mediterranean basin. Conversely, strong genetic differentiation appeared in the Atlantic basin. Even if the species was mostly philopatric (97%), results suggest recent dispersal between basins, especially from the Atlantic to the Mediterranean (aprox. 10% of migrants/generation across the last two generations). Long-term gene flow analyses also suggested an historical exchange between basins (about 70 breeders/generation). Spatial analysis of genetic variation indicates that distance is not the main factor in shaping genetic structure in this species. Given our results we recommend gathering more data before concluded whether these taxa should be treated as two species or subspecies.     

Molecular identification and genetic structure of Aedes phoeniciae (Diptera: Culicidae) in Northern Cyprus and Turkey

Aedes mariae, Aedes phoeniciae and Aedes zammitii are three sibling species of the Mariae complex with a limited distribution. All these three species use semi-saline/saline rock pool habitats on the coastal areas of Mediterranean countries. The Eastern coast of the Mediterranean basin, including Turkey and Cyprus coasts, is a unique distribution area for Ae. phoeniciae. This study was designed to identify three sibling species of the Mariae complex based on molecular markers and also to determine the distribution pattern and genetic structure of the Ae. phoeniciae along the eastern Mediterranean basin. Larval and adult samples of Ae. zammitii and Ae. phoeniciae were collected from different rock pool habitats along the coastal regions of Turkey and Northern Cyprus. Species identifications were done primarily based on morphological identification key. Identifications were supported by using mitochondrial DNA cytochrome oxidase I (COI) and nuclear DNA Internal transcribed spacer 2 (ITS2) sequences. Population genetic analyses of Ae. phoeniciae were implemented based on NADH dehydrogenase 4 (ND4) sequence and 17 haplotypes were detected in the study area. Analyses of molecular variance (AMOVA) determined that the majority of the variation was within the populations (60.15 %) while variation between groups was 30.68 % and the variation within groups was 9.17 %, indicating low genetic structuring among groups.     

The Taxonomic Status and Intraspecific Differentiation of the Black Sea Horse Mackerel, <Emphasis Type="Italic">Trachurus mediterraneus ponticus</Emphasis> (Aleev, 1956) (Carangidae)

The taxonomic status of the horse mackerel, Trachurus mediterraneus ponticus (Aleev, 1956), which inhabits the Black Sea, has been clarified based on the analysis of variation in the nucleotide sequence of the mtDNA cytochrome b (Cyt-b) locus. A comparison of this species with the horse mackerel from the Mediterranean basin and the World Ocean has shown that the Black Sea horse mackerel is neither an independent species nor a subspecies and can only be qualified as the species Trachurus mediterraneus (Steindachner, 1868) distributed throughout the Mediterranean Sea basin. A hypothesis has been made about the possible cause of the origin and existence of two forms, “large” and “small”, of the horse mackerel. By using the technique of calculating ontogenetic trajectories, it has been found that these are two morpho-ecological forms, whose differentiation is most likely determined by the type of feeding.     

Molecular Phylogeny and Ecology of Textularia agglutinans d’Orbigny from the Mediterranean Coast of Israel: A Case of a Successful New Incumbent

Textularia agglutinans d’Orbigny is a non-symbiont bearing and comparatively large benthic foraminiferal species with a widespread distribution across all oceans. In recent years, its populations have considerably expanded along the Israeli Mediterranean coast of the eastern Levantine basin. Despite its exceptionally widespread occurrence, no molecular data have yet been obtained. This study provides the first ribosomal DNA sequences of T. agglutinans complemented with morphological and ecological characterization, which are based on material collected during environmental monitoring of the hard bottom habitats along the Israeli Mediterranean coast, and from the Gulf of Elat (northern Red Sea). Our phylogenetic analyses reveal that all specimens from both provinces belong to the same genetic population, regardless their morphological variability. These results indicate that modern population of T. agglutinans found on the Mediterranean coast of Israel is probably Lessepsian. Our study also reveals that T. agglutinans has an epiphytic life mode, which probably enabled its successful colonization of the hard bottom habitats, at the Mediterranean coast of Israel, which consist of a diverse community of macroalgae. Our study further indicates that the species does not tolerate high SST (> 35°C), which will probably prevent its future expansion in the easternmost Mediterranean in light of the expected rise in temperatures.     

An account of the taxonomy and distribution of Syllidae (Annelida, Polychaetes) in the eastern Mediterranean, with notes on the genus Prosphaerosyllis San Martín, 1984 in the Mediterranean

The syllid fauna of three locations in Crete and Israel (eastern Mediterranean Sea) was studied, yielding 82 syllid species, many of which were found for the first time in the respective areas: Seventeen species were recorded for the first time on the Israeli coasts and 20 in Greek waters. Perkinsyllis augeneri (Hartmann-Schröder, 1979) and Prosphaerosyllis chauseyensis Olivier et al., 2011 are new records for the Mediterranean Sea. Detailed information is given on the morphology, ecology and distribution of the species recorded for the first time in the studied areas. In addition, an update on the distribution of the genus Prosphaerosyllis San Martín, 1984 in the Mediterranean is given and an identification key to the Mediterranean species is provided.     

Imbalanced diversification of two Mediterranean sister genera (Bellis and Bellium, Asteraceae) within the same time frame

The Daisies, Bellis and Bellium, form a monophyletic complex within the core Astereae (Asteraceae). Although most early diverging lineages show an African distribution, the core Astereae is today widespread on five continents with the Bellis/Bellium complex as the only representative in the Mediterranean basin. Molecular clock estimates placed the divergence of Astereae from its sister tribe Anthemideae in the Oligocene. Using a combination of three plastid genes, we estimated divergence times for different lineages of the tribe Astereae. This, together with temporal and biogeographical reconstructions using the nrITS region, allows placing and timing of the major lineages of the Bellis/Bellium complex. The age reconstruction places the divergence of the tribe Astereae in the late Miocene (18?C19?million years ago), followed by an out-of-Africa dispersal into Asia where the worldwide expansion may have started. Our results suggest that the colonization of the Mediterranean basin by the Astereae started from Eurasia some 10?million years ago. A Messinian early divergence of the Bellis/Bellium complex in the Mediterranean was estimated. However, a parallel 4-million-year delay for the within-genera diversification was inferred, probably related to the establishment of the sclerophyllous Mediterranean forest. Despite a similar time frame for the within-genera diversification, today??s species numbers differ considerably between Bellis (15 spp.) and Bellium (five spp.).     

Distribution of recent planktonic foraminifera in surface sediments of the Mediterranean Sea

The Mediterranean Sea is a partillay isolated ocean where excess evaporation over precipitation results in large east to west gradients in temperature and salinity. Recent planktonic foraminiferal distributions have been examined in 66 surface sediment samples from the Mediterranean Sea. In addition to mapping the frequency distribution of 16 species, the faunal data has been subjected to cluster analysis, factor analysis and species diversity analysis. The clustering of species yields assemblages that are clearly temperature related. A warm assemblage contains both tropical and subtropical elements, while the cool assemblage can be subdivided into cool-subtropical, transitional and polar-subpolar groupings. Factor analysis is used to delineate the geographic distribution of four faunal assemblages. Factor 1 is a tropical-subtropical assemblage dominated by Globigerinoiden ruber. It has its highest values in the warmer eastern basin. Transitional species (Globorotalia inflata and Globigerina bulloides) dominate factor 2 with highest values occurring in the cooler western basin. Factor 3 reflects the distribution of Neogloboquadrina dutertrei and is considered to be salinity dependent. Subpolar species dominate factor 4 (Neoglobuquadrina pachyderma and G. bulloides), with highest values occurring in the northern part of the western basin where cold bottom water is presently being formed. The Shannon-Weiner index of species diversity shows that high diversity exists over much of the western basin and immediately east of the Strait of Sicily. This region is marked by equitable environmental conditions and relatively even distribution of individuals among the species. Conversely, in areas where temperature and salinity values are more extreme, diversity values are lower and the assemblages are dominated by one or two species.     

Redescription of Fabriciola tonerella Banse, 1959, and a new record of Novafabricia infratorquata (Fitzhugh, 1983) from the Mediterranean Sea, with a key for the Fabriciinae (Annelida: Polychaeta) of the Mediterranean Sea and the north-east Atlantic

The fabriciin sabellid species Fabriciola tonerella Banse, 1959 living on gastropod shells inhabited by hermit crabs collected in the western Mediterranean Sea is redescribed. Another species of Fabriciinae, Novafabricia infratorquata (Fitzhugh, 1983), is recorded for the first time from the Mediterranean Sea and found in the same habitat is described as well. The variability of characters depending on size and geographical distribution is given for both species. Moreover, selected characters for all known species of Fabriciola and Novafabricia as well as a simple key for all Fabriciinae of the Mediterranean Sea and the north-east Atlantic are provided.     

Conservation genetics of the short-beaked common dolphin (<Emphasis Type="Italic">Delphinus delphis</Emphasis>) in the Mediterranean Sea and in the eastern North Atlantic Ocean

Mediterranean Sea common dolphins have recently been listed as ‘endangered’ in the IUCN Red list, due to their reported decline since the middle of the 20th century. However, little is know about the number or distribution of populations in this region. We analysed 118 samples from the Black Sea, Mediterranean Sea and eastern North Atlantic at nine microsatellite nuclear loci and for 428 bps of the mtDNA control region. We found small but significant population differentiation across the basin between the eastern and the western Mediterranean populations at both nuclear and mtDNA markers (microsatellite F _ST = 0.052, mtDNA F _ST = 0.107, P values ≤ 0.001). This matched the differential distribution and habitat use patterns exhibited by this species in the eastern and the western parts of the Mediterranean Sea. The assignment test of a small number of samples from the central Mediterranean could not exclude further population structure in the central area of the basin. No significant genetic differentiation at either marker was observed among the eastern north Atlantic populations, though the Alboran population (inhabiting the Mediterranean waters immediately adjacent the Atlantic ocean) showed significant mtDNA genetic differentiation compared to the Atlantic populations. Directional estimates of gene flow suggested movement of females out of the Mediterranean, which may be relevant to the population decline. Phylogenetic analysis suggested that the observed population structure evolved recently.     

New insights into the genetic diversity of zooxanthellae in Mediterranean anthozoans

Symbiotic dinoflagellates of the genus Symbiodinium, also called zooxanthellae, are found in association with a wide diversity of shallow-water anthozoans. The Symbiodinium genus includes numerous lineages, also referred to as clades or phylotypes, as well as a wide diversity of genetic sub-clades and sub-phylotypes. There are few studies characterizing the genetic diversity of zooxanthellae in Mediterranean anthozoans. In this study, we included anthozoans from the Western Mediterranean Sea and by means of internal transcriber (ITS) and large sub-unit (LSU) rRNA markers we corroborate what has been previously identified, demonstrating that phylotype “Temperate A” is very common among host Cnidaria in this basin. Our finding of fixed differences in ITS and LSU markers that correspond to different host taxa, indicate that this clade may comprise several closely-related species. Previous studies have reported the occurrence of Symbiodinium psygmophilum (formerly sub-clade B2) associated with Oculina patagonica and Cladocora caespitosa in the Eastern Mediterranean. Here, we identify this association in O. patagonica from the Western Mediterranean but not in C. caespitosa, suggesting some differences in symbiotic combinations between the Western and Eastern Mediterranean Basins.     

Multilocus approach reveals an incipient differentiation process in the Stone-curlew, <Emphasis Type="Italic">Burhinus oedicnemus</Emphasis> around the Mediterranean basin

The Stone-curlew Burhinus oedicnemus, a steppe bird species, is mainly distributed in the Mediterranean and Macaronesian regions, which are considered hotspots of biodiversity with priority for animal and plant species richness conservation. In this study, we investigated the genetic diversity of the Stone-curlew in the Mediterranean basin and in the Canary Islands by applying a multilocus approach. We analysed mitochondrial and nuclear markers in order to evaluate the genetic structure and the congruence between morphological subspecies and geographic samples. We found a significant level of genetic differentiation between Mediterranean and Canary Island populations with all markers. Both in the Mediterranean basin and in the Canary Islands, we found a significant level of genetic diversity with nuclear markers only. We identified seven population groups, including insular populations. The four subspecies described for the Western Palaearctic were confirmed with some changes in distribution range. In spite of habitat fragmentation and negative population trend, the Stone-curlew showed a significant level of genetic diversity and gene flow among continental populations. However, islands constitute important reservoirs of genetic diversity and a potential for the evolution of the species.     

The tropical caprellid amphipod Paracaprella pusilla: a new alien crustacean in the Mediterranean Sea

Paracaprella pusilla Mayer (Fauna und Flora des Golfes von Neapel 17:1–55, 1890), originally described from Brazil, is one of the most abundant caprellid amphipod species in tropical and subtropical seas around the world. During a survey of caprellid amphipods from marinas along the Balearic Island (Western Mediterranean Sea) carried out between November 2011 and August 2012, we found two established populations of P. pusilla in Mallorca and Ibiza, respectively. So far, its occurrence in European waters was reported only from southwestern Spain in 2010. This record represents a northward range expansion of the species’ distribution, which is found for the first time in the Mediterranean. This is also the first record of the genus Paracaprella in the Mediterranean Sea. The most probable introduction vector was ship fouling. We also found the invasive caprellid Caprella scaura Templeton (Trans Entomol Soc Lond 1:185–198, 1836) in Mallorca and Menorca, which is recorded for the first time in the Balearic Islands, confirming its rapid expansion along the Mediterranean. When comparing reproductive traits between both alien species, we found that P. pusilla has a higher fecundity than C. scaura for the same female size. Taking into account this evidence, the species may be expected to appear in other Mediterranean and adjacent areas.     

New insights into seminal and stomatal morphology and their contribution to the taxonomy of the Old World succulent perennial Salicornioideae

Seminal and stomatal morphology of three succulent halophyte genera (Sarcocornia, Halocnemum and Arthrocnemum) around the Mediterranean basin and surroundings areas were investigated. Scanning electron microscopy (SEM) investigations showed well-different seminal coat ornamentations among the studied taxa. Both Arthrocnemum macrostachyum and Halocnemum strobilaceum do not show trichomes. Conversely, the species Sarcocornia perennis and S. fruticosa can be easily identified by the presence of long curved hairs against papillae or short conic hairs, respectively. Because most of the herbarium vouchers of Sarcocornia lack seeds, and thus the permanency of seeds on plants is quite short, an alternative vegetative character as stomata was also studied using SEM and light microscope. The detailed stomatal morphological features were analysed for the first time to infer taxonomic relationships among these perennial halophytes. Stomata are constantly paracytic for the four studied species, but two morphotypes were identified related to the level arrangement of guard cells, named as sunken and prominent stomata, respectively. Sunken stomata are found in A. macrostachyum, H. strobilaceum and S. fruticosa, whereas prominent stomata are only characteristic for S. perennis. Besides, we have found somehow relationships among the ecology of these plants based on the frequency of floodings and the observed morphology and density of stomata. Nonetheless, each observed morphotype is a stable character, without any influence of climate or environmental conditions. As a result, seminal coat ornamentation and stomata morphology are the two most reliable characteristics for discriminating Mediterranean halophytes taxa, especially related to Sarcocornia taxa.     

Les assemblages de diatomées du bassin messinien de Boudinar (Maroc nord-oriental)

The Messinian is one of the strongest biogenic silica accumulation periods in the world and more particularly in the Mediterranean, where it is marked by an important diatomitic sedimentation. In the Boudinar basin (Morocco north-Eastern, Western Mediterranean), the section of Sidi Haj Youssef, localised near the volcano of Ras Tarf, has approximately 100 m thickness of clayey-marly series in which 12 diatomitic levels of variable thickness are intercalated. The microfloristic study of diatoms on 86 samples, carried out in detail for the first time, made it possible to recognize 50 genus of diatoms (24 of centric and 26 of pennate) represented by 185 species (75 species of centric and 110 species of pennate). Four hundred individuals were taken from each sample to determine the relative frequency of each taxon within the diatoms assemblages. Thus, several assemblages were defined by the predominance of the following species: Coscinodiscusmarginatus, Actinoptychussenarius, Thalassionemanitzschioides, Actinocycluscurvatulus, Thalassiothrixlongissima, Rhizosoleniastyliformis and Actinocyclusehrenbergii. These diatoms assemblages display a littoral marine environment in communication with the opened sea. The abundance of the cold water species towards the base and the top of the section suggests broad exchanges of the basin with the Atlantic Ocean in Messinian. The predominance of the species Thalassionemanitzschioides and/or Thalassiothrixlongissima indicates periods of strong productivity that can be associated to upwelling systems.     

Colonization of the Mediterranean basin by the vector biting midge species Culicoides imicola: an old story

Understanding the demographic history and genetic make‐up of colonizing species is critical for inferring population sources and colonization routes. This is of main interest for designing accurate control measures in areas newly colonized by vector species of economically important pathogens. The biting midge Culicoides imicola is a major vector of orbiviruses to livestock. Historically, the distribution of this species was limited to the Afrotropical region. Entomological surveys first revealed the presence of C. imicola in the south of the Mediterranean basin by the 1970s. Following recurrent reports of massive bluetongue outbreaks since the 1990s, the presence of the species was confirmed in northern areas. In this study, we addressed the chronology and processes of C. imicola colonization in the Mediterranean basin. We characterized the genetic structure of its populations across Mediterranean and African regions using both mitochondrial and nuclear markers, and combined phylogeographical analyses with population genetics and approximate Bayesian computation. We found a west/east genetic differentiation between populations, occurring both within Africa and within the Mediterranean basin. We demonstrated that three of these groups had experienced demographic expansions in the Pleistocene, probably because of climate changes during this period. Finally, we showed that C. imicola could have colonized the Mediterranean basin in the Late Pleistocene or Early Holocene through a single event of introduction; however, we cannot exclude the hypothesis involving two routes of colonization. Thus, the recent bluetongue outbreaks are not linked to C. imicola colonization event, but rather to biological changes in the vector or the virus.