Hidden diversity of Euscorpius (Scorpiones: Euscorpiidae) in Greece revealed by multilocus species‐delimitation approaches

Phylogenetic analysis of the genus Euscorpius (Scorpiones: Euscorpiidae) across the Mediterranean region (86 specimens, 77 localities, four DNA markers: 16S rDNA, COI, COII, and ITS1), focusing on Greek fauna, revealed high variation, deep clade divergences, many cryptic lineages, paraphyly at subgenus level, and sympatry of several new and formerly known lineages. Numerous specimens from mainland and insular Greece, undoubtedly the least studied region of the genus' distribution, have been included. The reconstructed phylogeny covers representative taxa and populations across the entire genus of Euscorpius. The deepest clades detected within Euscorpius correspond (partially) to its current subgeneric division, outlining subgenera Tetratrichobothrius and Alpiscorpius. The rest of the genus falls into several clades, including subgenus Polytrichobothrius and a paraphyletic subgenus Euscorpius s.s. Several cryptic lineages are recovered, especially on the islands. The inadequacy of the morphological characters used in the taxonomy of the genus to delineate species is discussed. Finally, the time frame of differentiation of Euscorpius in the study region is estimated and the distributional patterns of the lineages are contrasted with those of other highly diversified invertebrate genera occurring in the study region. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2013, 110 , 728–748.     

Species‐specific responses to island connectivity cycles: refined models for testing phylogeographic concordance across a Mediterranean Pleistocene Aggregate Island Complex

The contribution of Pleistocene sea level changes to diversification patterns in archipelagos around the world, and specifically whether the repeated cycles of island connectivity and isolation acted as a ‘species pump’ is debated. The debate has been perpetuated in part because of the type of evidence used to evaluate the species‐pump hypothesis. Specifically, existing tests of the ‘Pleistocene Aggregate Island Complex’ (PAIC) model of diversification interpret the lack of concordant divergence times among multiple codistributed taxa as a rejection of the PAIC model. However, the null expectation of concordance disregards taxon‐specific ecological traits and geographic characteristics that may affect population persistence and gene flow among islands. Here, we study the factors affecting population divergence in thirteen flightless darkling beetle species (Coleoptera: Tenebrionidae) across the PAIC system of the Cycladic plateau in the Aegean archipelago. Based on isolation‐by‐resistance analyses, hierarchical amova and the degree of genealogical sorting on individual islands, we identify a major effect of bathymetry and habitat stability on the levels of genetic divergence across the PAIC, with island size and body size playing a secondary role as well. We subsequently use bathymetric maps and habitat association to generate predictions about the set of islands and group of taxa expected to show phylogeographic concordance. We test these predictions using hierarchical approximate Bayesian computation and show how our interpretations regarding the role of PAICs as drivers of divergence change when relying on a null expectation of concordance compared to a refined model that takes geography and ecological traits into account.     

Deep-sea ecosystem variability of the Aegean Sea during the past 22 kyr as revealed by Benthic Foraminifera

Specific responses of the regional deep-sea ecosystems to climatic and oceanographic processes during the last 22 kyr are revealed by benthic foraminiferal faunas from two cores in the northern and southern Aegean Sea. Under glacial boundary conditions, high-diversity benthic foraminiferal faunas and elevated benthic foraminiferal numbers indicate enhanced organic matter availability and well-ventilated deep-water masses in the whole Aegean Sea. The glacial termination is accompanied by significant fluctuations in productivity and deep-water ventilation. In the northern Aegean Sea, meltwater inflow from mountain glaciers during the Bølling/Allerød warm period resulted in a restriction of local deep-water formation, as mirrored by a dominance of bolivinids. During the deposition of sapropel S1, drops in benthic foraminiferal number and diversity are more significant in the southern Aegean Sea when compared to the north. This suggests the persistence of local deep-water formation in the northern Aegean Sea during S1 deposition. In addition, faunal fluctuations within S1 at both sites suggest the repeated influence of short-term cooling events on the re-ventilation and re-colonization of Aegean deep-sea ecosystems. During the middle and late Holocene, benthic foraminiferal faunas document the establishment of oligotrophic and well-ventilated conditions in the southern Aegean Sea. The corresponding faunas from the northern Aegean Sea reflect generally mesotrophic conditions and variable deep-water oxygenation. During the entire Holocene, the deep-sea ecosystems of this region responded very sensitively to short-term changes in humidity and temperature. These abrupt climate changes controlled the inflow of nutrients from rivers and the Black Sea and the formation of local deep-water masses.     

Environmental influences on the spatial distribution of European hake (Merluccius merluccius) and red mullet (Mullus barbatus) in the Mediterranean

Generalised additive models (GAMs) were used to test the hypotheses that red mullet (Mullus barbatus) and hake (Merluccius merluccius) abundances are related to the bathymetry, spatial location and the temperature-based variability of the NE Mediterranean. Data were collected during a 2-year period (1996–1997) of quasi-synoptic sampling using demersal trawl surveys in the northern Aegean Sea. The results of this study supported these hypotheses. It was found that geographic position and sea bottom characteristics influence the temporal distribution patterns of red mullet and hake. Data are presented that reveal species-specific aggregation patterns and an important habitat utilisation of the area. The modelled species’ abundances showed a strongly non-linear dependence on the explanatory covariates. This study, although not directly dealing with spawning, also provided evidence that red mullet and hake demonstrate environmental and bathymetric preferences in the months posterior to spawning. Mean red mullet abundance was consistently highest in areas with warmer bottom waters in the east and west than in the centre, these areas having shallower depths (35–60 m) and bottom temperatures around 19°C. The red mullet appeared to avoid the cold bottom waters (<16°C) of the deeper regions. Results indicated that areas with the highest hake abundances were located in waters of ∼160 m having bottom temperature of ∼16°C and avoided the shallower waters (<70 m) regardless of their bottom temperature. The present findings also suggested that colder bottom waters at all depths were associated with lower-than-average hake abundance. Red mullet and hake preferences for areas with specific bathymetric and ocean environmental conditions are believed to be linked to the oceanography of the NE Mediterranean ecosystem.     

Two records of sea lamprey from the north Aegean Sea

Two adult sea lampreys Petromyzon marinus , one female and one male, 742 and 645 mm L _T respectively, were caught in the north Aegean Sea, Greece (Vistonis bay and shore of Karvali). These two records are the first for the Aegean Sea and for the whole eastern Mediterranean.     

Molecular phylogeny and phylogeography of the Greek populations of the genus Orthometopon (Isopoda, Oniscidea) based on mitochondrial DNA sequences

We infer phylogenetic relationships among isopod species of the genus Orthometopon distributed in the Greek area, comparing partial mitochondrial DNA sequences for cytochrome oxidase I (COI). All phylogenetic analyses produced topologically identical trees that revealed a well-resolved phylogeny. These trees support the monophyly of the genus Orthometopon , and suggest two clades that correspond to separate geographical regions (west and east of the mid-Aegean trench). However, the phylogenetic relationships among Greek populations of Orthometopon spp. are different from the presumed pattern on the basis of morphological evidence. The distinct geographical distribution of the major clades of the phylogenetic tree and its topology suggest a spatial and temporal sequence of phylogenetic separations, which coincide with some major palaeogeographical separations during the geological history of the Aegean Sea. The results stress the need for a reconsideration of the evolutionary history of Orthometopon species, which will help overcome difficulties encountered in classical taxonomy at the species level. © 2008 The Linnean Society of London, Zoological Journal of the Linnean Society , 2008, 152 , 707–715.     

A biogeographical analysis of terrestrial isopods (Isopoda, Oniscidea) from the central Aegean islands (Greece)

Abstract. Terrestrial isopods (Isopoda, Oniscidea) of forty-three central Aegean islands and islets are analysed from a biogeographical point of view. The oniscid fauna consists of sixty-nine species, thirty-two genera and fourteen families and is characterized by Aegean elements that have an eastern Mediterranean origin. Endemism is at the level of 20%, similar to that of oniscids from other Mediterranean archipelagoes. Analysis of species distribution through both idiographic and quantitative approaches (faunal similarity among islands using Jaccard's index, simple matching indices and the UPGMA clustering technique) resulted in the recognition of a major disjunction between Kykladesplus-Ikaria and eastern islands-plus-Astypalea and four noteworthy island groups: the eastern islands, Naxos-Ikaria, Amorgos, and all other Kyklades. Island similarities are generally consistent with the known palaeogeography of the area with the exception of Ikaria's placement with Naxos among the Kyklades. Also, the 'eastern' character of Astypalea is in conflict with evidence from other known taxa.     

Lessepsian migrant Fistularia commersonii from the Rhodes marine area

The bluespotted cornetfish Fistularia commersonii which originates from the Red Sea, appeared in the marine area of Rhodes Island (south-east Aegean Sea). This is a new record of the species based on 37 specimens caught during summer-winter 2001. The species appears to be spreading rapidly west and easily becoming established in Mediterranean coastal habitats.     

Demersal trawl discards with spatial and bathymetric emphasis in the Turkish coast of the Aegean Sea

The aim of the present study is to investigate the spatial and bathymetric distribution of demersal trawl discards in the Turkish coast of the Aegean Sea. Trawl hauls were performed in the legal trawling areas of the Turkish coast of the Aegean Sea (Çanakkale, Foça, Karaburun, S??ac?k, Güllük) between 2010 and 2012 by commercial trawlers. Depth of the trawl hauls ranged from 30?m in the south to 450?m in the north. As a result of 311 trawl samples, 200 species belonging to eight taxonomic groups (Porifera, Cnidaria, Annelida, Arthropoda, Mollusca, Echinodermata, Tunicata, Chordata) were identified. The changes in species composition based on depth and region were determined to be statistically significant. It was found that species composition distinctly changed around 200?m. In a regional assessment it was determined that the Turkish coast of the Aegean Sea is divided into three sub-regions, i.e. Çanakkale, Foça-Karaburun-S??ac?k and Güllük. The results of similar studies conducted in the Mediterranean were investigated and compared with the findings of this study.     

Secondary States in Perspective: An Integrated Approach to State Formation in the Prehistoric Aegean

In this article, we explore the typological distinction between primary and secondary states. We outline a methodology for exploring variability in the formation and organization of secondary states that integrates aspects of traditional neoevolutionary approaches, Marcus's "dynamic model," Blanton et al.'s "dual-processual model," and world-systems theory. We discuss the development of the Minoan and Mycenaean states of the Bronze Age Aegean and argue that they arose via different mechanisms of secondary state formation, through direct and indirect contact with neighboring societies in the Eastern Mediterranean, Near East, and Egypt. We argue that a model that measures state formation along several different theoretical dimensions encourages archaeological exploration of secondary states along varied historical trajectories, in different (pre)historic contexts.     

Dietary habits of the deep-sea flatfish Lepidorhombus boscii in north-eastern Mediterranean waters

Stomach content analysis of four-spotted megrim Lepidorhombus boscii in the oligotrophic Aegean Sea revealed that specimens with fully filled stomachs were rarely encountered. The overall dietary breadth of the species appeared to increase in winter and spring, when stomachs fullness was reduced. The species exhibited a relatively high trophic diversity and could be considered a euryphagous carnivore preying mainly upon crustaceans. Decapod natants, namely Processa canaliculata and Alpheus glaber , dominated in terms of per cent mass, while mysids, represented mainly by Lophogaster typicus , were the most important dietary component in terms of per cent number. Isopods, amphipods and decapod brachyurans were also frequently encountered among stomach contents. Fishes were only ingested by larger specimens (>180 mm total length, L _T); mouth gape dimensions increasing in larger specimens, enabled them to consume larger organisms. Discriminant function analysis showed that size and then sex of predators had the highest weight in discriminating the dietary groups produced by cluster analysis. Resource partitioning along the trophic dimension seemed to exist among smaller males and females (<110 mm L _T), which also presented significant differences in their mouth gape dimensions. The study of the diel feeding pattern of the species demonstrated that foraging activity took place day and night, while observed qualitative differences might partly reflect variations in prey availability on a 24 h basis.     

Assessment of site specific benthic impact of floating cage farming in the eastern Hios island, Eastern Aegean Sea, Greece

The site specific impact on the benthic fauna was assessed within a 4.64 km² area of intensive aquaculture situated on the eastern side of Hios island (Aegean Sea, Greece) at 11 stations seasonally between November 2000 and October 2001. The benthic fauna showed marked changes in species numbers, diversity and faunal abundance between farm and control sites. The polychaetes Nereis diversicolor, Scolelepis fuliginosa and Capitella capitata were the most dominant species at the farm sites (35% of the total abundance), whilst the most dominant species at the control sites were the polychaete Hyalinoecia brementi and the sipunculid Aspidosiphon muelleri (23% of the total abundance). Species richness, diversity and evenness were higher at the control sites whereas numerical abundance was higher at the farm sites. K-dominance curves suggest a minor impact on the benthic community at the farm sites and temporal changes on macrobenthic assemblages.     

Polychaetes associated with the sciaphilic alga community in the northern Aegean Sea: spatial and temporal variability

Polychaete biodiversity has received little attention despite its importance in biomonitoring. This study describes polychaete diversity, and its spatial and temporal variability in infralittoral, hard substrate assemblages. Seven stations were chosen in the central area of the northern Aegean Sea. At each station, one to three depth levels were set (15, 30 and 40 m). Five replicates were collected by scuba diving with a quadrat sampler (400 cm²) from each station and depth level during summer for the spatial analysis, and seasonally for the study of temporal changes. Common biocoenotic methods were employed (estimation of numerical abundance, mean dominance, frequency, Margalefs richness, Shannon-Weaver index and Pielous evenness). A total of 5,494 individuals, belonging to 79 species, were counted and classified. Diversity indices were always high. Clustering and multidimensional scaling techniques indicated a high heterogeneity of the stations, although these were all characterized by the sciaphilic alga community. A clear seasonal pattern was not detectable. Summer and autumn samples discriminate, while winter and spring form an even group. The abundance/biomass comparison indicated a dominance of k-strategy patterns, characteristic of stable communities.Communicated by H.-D. Franke     

Seasonal variations of microphytoplankton assemblages and environmental variables in the coastal zone of Bozcaada Island in the Aegean Sea (NE Mediterranean Sea)

Seasonal changes in the microphytoplankton assemblages were examined in the coastal zone of Bozcaada Island with regard to some major physical and chemical variables. Samples were collected from May 2000 to December 2001 at four stations. A total of 108 dinoflagellates, 102 diatoms, 1 chrysophycean, 3 dictyochophycean, and 1 prasinophycean species were identified and quantified during the study period. Diatoms and dinoflagellates were the most important in terms of species number and abundance. The maximum values of total microphytoplankton were observed at 0.5 m depth (46.2 × 10³ cells l⁻¹ at st. 3) in May as this was the month when the diatom Pseudo-nitzschia pungens bloomed. Chlorophyll (chl) a concentration ranged between 0.08 (August) and 0.78 μg l⁻¹ (February). May was another important month in which chlorophyll a increased (0.41–0.47 μg l⁻¹). Species diversity values (H′_log2) ranged from 1.66 bits (June, 20 m) to 4.11 bits (November, 0.5 m). The increase was attributed to a more balanced distribution of abundance among species. The amounts of nitrate + nitrite (0.6−3.7 μg-at N l⁻¹), phosphate (0.2−0.6 μg-at P l⁻¹) and silicate (0.7−2.5 μg-at Si l⁻¹) were recorded on each sampling occasion. Nutrient concentrations and chl a values of the research area were found to be poorer than those of the many other coastal areas in the northeastern Mediterranean. The mean atomic ratio of nitrogen to phosphorus varied from 1.3 (June) to 12.9 (February). This ratio was lower than the Redfield ratio of 16 for ocean phytoplankton, and phytoplankton was potentially limited by nitrogen for most of the months. The result of this study confirms and emphasizes the oligotrophic nature of the eastern Mediterranean.     

Coastal fish otoliths from the early Pleistocene of Rhodes (eastern Mediterranean)

Coastal fish assemblages are especially vulnerable to environmental changes, but little is known about their evolution through time, mainly due to the scarcity of fossil material from such settings. The aim of this study is to characterize the early Pleistocene coastal fish assemblages of the eastern Mediterranean and to reconstruct the related paleobathymetric and paleoecologic conditions. Based on otolith findings, we identified thirty-seven teleost fish species from three sedimentary outcrops on the northeastern part of Rhodes Island (southeastern Aegean, Greece, Eastern Mediterranean), which have been placed within the Gelasian (early Pleistocene). The stratigraphic distribution of fifteen taxa is expanded for this interval, while five species are reported for the first time as fossils. The otolith assemblages provided paleodepth estimates indicative of shallow coastal environments. The ecosystem consisted mostly of substrates of sand and mud, with significant rocky micro-habitats and underwater vegetation; the climate was subtropical. These data complement existing knowledge on the study area, while providing new information on the composition of the ichthyofauna of the eastern Mediterranean during the Gelasian.     

Homo‐C‐nucleoside analogs IV. Synthesis of 4‐(2,5‐anhydro‐D‐altro‐pentitol‐1‐yl)‐2‐phenyl‐2H‐1,2,3‐triazole homo‐C‐nucleoside. CD assignment of the absolute configuration of the carbon bridge

Dehydrative cyclization of 4‐(D‐altro ‐pentitol‐1‐yl)2‐phenyl‐2H ‐1,2,3‐triazole in basic medium with one moler equivalent of p‐toluene sulfonyl chloride in pyridine solution gave the homo‐C‐ nucleoside 4‐(2,5‐anhydro‐D‐altro ‐1‐yl)‐2‐phenyl‐2H ‐1,2,3‐triazole. The structure and anomeric configuration was determined by acylation, nuclear magnetic resonance (NMR), and mass spectroscopy. The stereochemistry at the carbon bridge of homo‐C‐ nucleoside 2‐phenyl‐2H ‐1,2,3‐triazoles was determined by circular dichroism (CD) spectroscopy.     

Modelling potential habitat of the invasive ctenophore <Emphasis Type="Italic">Mnemiopsis leidyi</Emphasis> in Aegean Sea

The invasive ctenophore Mnemiopsis leidyi was accidentally introduced into the Black Sea in the early 1980s and it was first sighted in the Aegean Sea (Eastern Mediterranean) in the early 1990s. This article presents a first attempt to develop a predictive spatial model based on M. leidyi presence data and satellite environmental data from the Aegean Sea during early summer, in order to identify those areas in the Greek Seas and the entire Mediterranean basin that could serve as potential habitat for the species. Generalized additive models (GAM) were applied. The final GAM model indicated higher probability of finding M. leidyi present in depths of 65–135 m and sea surface temperature values of 21–25°C. Furthermore, the significant interaction between photosynthetically active radiation (PAR) and sea level anomaly (SLA) indicated a higher probability of M. leidyi presence in low values of PAR and SLA. In the next step, the final GAM was applied in a prediction grid of mean monthly satellite values for June 2004–2006 in order to estimate probability of M. leidyi presence in the Hellenic Seas and the whole Mediterranean basin at a GIS resolution of 4 km. In the Aegean Sea, species potential habitat included areas influenced by the Black Sea Water (e.g. Thracian Sea, Limnos-Imvros plateau), gulfs that are affected by river runoffs, such as the Thermaikos, Strymonikos and Patraikos gulfs, or areas with strong anthropogenic influence such as the Saronikos gulf. Areas with the same environmental conditions as those in Aegean Sea have been indicated in certain spots of the Levantine Sea as well as in coastal waters of Egypt and Libya, although their spatial extent varied largely among years examined. However, the occurrence of conditions that are linked to high probability of M. leidyi presence does not necessarily mean that these areas can support successful reproduction, high population or bloom levels, since these depend on a combination of temperature, salinity, food availability and the abundance of predators. Guest editor: V. D. Valavanis Essential Fish Habitat Mapping in the Mediterranean     

Genetic differences between populations of sardine, Sardina pilchardus, and anchovy, Engraulis encrasicolus, in the Aegean and Ionian seas

Genetic distances based on electrophoretic variation and multivariate analysis of several morpho-metric and meristic characters suggest that populations of sardine and anchovy from the Aegean and Ionian seas do not form one panmictic population. The distinction between these two classes of populations emerges only as a statistical property, and for some characters the within-sea variation is larger than the between-sea variation. Thus, the reproductive isolation between populations inhabiting the two seas appears to be only partial. Our findings do not support the' pure' or' discrete' stock concept. Instead, they provide evidence for the dynamic population structure model according to which physical (e.g., hydrographic) or biological (e.g., predation or behaviour) factors impose a population structure maintained in a semi-equilibrium state under the opposing influences of migration and selection. Such a dynamic state may not be stable in the long run, and it may not allow for the accumulation of genetic divergence necessary for the emergence of higher taxa. It must, nevertheless, be taken into account in the management of exploited natural populations.     

Bacteria associated with the sponge Spongia officinalis as indicators of contamination

A lot of micro-organisms can been found in the sponge body. In the present study, bacteria and fungi were isolated from the massive commercial sponge Spongia officinalis Linnaeus, 1759 (Porifera, Demospongiae). Samples (sponge extract and sea water) were collected from several areas of the Aegean Sea (ports, beaches, eutrophic gulf and open sea) with different levels and types of contamination. Bacteria identified in sponge extract belong to the genera Escherichia, Morganella, Proteus, Pasteurella, Aeromonas, Pseudomonas and Acinetobacter. Two fungal genera, Trichosporum and Fisarium, were identified in sponge extract. Bacterial load was greater in sponge extract than in proximal sea water, reflecting the sponge ability to concentrate bacteria in its body. The assessment of bacteria associated with the sponge S. officinalis as indicators of contamination is proposed.