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Zonites Montfort, 1810 is recorded for the first time from Paros island. As only an old shell was found, the reasons that the populations of this threatened, endemic land snail of the Aegean seem to be declining should be investigated.

Islands occupy a proportionately small area on Earth, however they play a crucial role in Ecology and Biogeography, as they constitute “natural laboratories”. The increased number of species, with increasing island area, is such a commonly observed pattern that it has been labelled as one of the few laws of ecology. The Aegean archipelago is of broad biogeographical interest, as it has a considerable number of islands in addition to a rich paleogeographical and geological history, while being divided among three continents (Europe, Asia, Africa). As a result, the composition of life in the Aegean is dominated by species of European, Asian, African origin as well as species endemic in the archipelago. In this framework, we approached the species–area relationship (SAR) of the Aegean islands for six different organismic groups (birds, herptiles, snails, isopods, tenebrionids and chilopods) and 20 different models. The aim was to determine which model(s) perform better for each taxon and also to compare the z and C parameters of the power model between animal groups, which are the only model parameters to date that have been linked with biological processes. We compared the relationship across different taxa for the entire archipelago and for the exact same islands, in two subgroups with similar paleogeographic history and environmental conditions in the central and eastern Aegean. For the taxonomic groups that were examined a strong correlation between the number of species and area was found, except for chilopods and herptiles. Although there is no universal best model for the SAR of the Aegean, the power model performed better for invertebrates, whereas concerning vertebrates there was more ambiguity in the shape of the relationship.

Albinaria (Gastropoda, Clausiliidae) is a pulmonate genus distributed around the north-eastern coasts of the Mediterranean. It is the most 'speciose' genus within the family of Clausiliidae, exhibiting a high degree of morphological and genetic differentiation, and serving as a model for several ecological, systematics and evolutionary studies. Nevertheless, many aspects remain uncertain mainly due to the large number of taxa whose classification has not yet been evaluated with solid synapomorphic characters. Thirty-one morphological species are currently recognized on the island of Crete and its satellite islets. Four of them (A. retusa, A. torticollis, A. jaeckeli, and A. teres) are distributed on the island of Dia (north of Crete); the first three are island endemics. Here, we combined mitochondrial and nuclear DNA information and Bayesian and Maximum Likelihood approaches to evaluate the phylogenetic relationships, and assess the genetic distinctiveness and cohesiveness of all described species of Dia...

Global urbanization is a major force that causes alteration and loss of natural habitats. Urban ecosystems are strongly affected by humans and there is a gradient of decreasing human influence from city centers to natural habitats. To study ecological changes along this continuum, researchers introduced the urban-rural gradient approach. The responses of centipedes to an urbanization gradient (urban-suburban-rural areas) were studied using pitfall traps in and near the city of Heraklion, in the island of Crete, Greece, from November 2010 to November 2011. Our results do not support the intermediate disturbance hypothesis, in which suburban areas located in the transitional zone between urban and rural habitats failed to indicate significant increase in terms of species richness and diversity.

Phylogenetic relationships of the Aegean Helix cincta and Helix nucula with congeneric species found in Greece were inferred using mitochondrial DNA sequence data. Twenty-three specimens from mainland Greece, Aegean Islands, Cyprus and North Africa were analysed, revealing that (1) H. nucula is monophyletic, (2) H. cincta from Greece and Cyprus is paraphyletic, and so questions arise regarding the taxonomy of this species, and (3) H. cf. cincta from Tunisia might be considered as a distinct evolutionary lineage. Moreover Helix valentini, an endemic species of Kalymnos Island group, is clustered within the lineage of H. c. anatolica, so supporting the synonymy of the two ‘species’, and the elevation of H. c. anatolica to species level. Hence, our results stress the need for a taxonomic reconsideration of H. cincta in the Aegean Sea, indicating that sequence data can prove useful in overcoming taxonomic issues at both species and subspecies level.

Albinaria (Gastropoda, Clausiliidae) is a pulmonate genus distributed around the north-eastern coasts of the Mediterranean. It is the most 'speciose' genus within the family of Clausiliidae, exhibiting a high degree of morphological and genetic differentiation, and serving as a model for several ecological, systematics and evolutionary studies. Nevertheless, many aspects remain uncertain mainly due to the large number of taxa whose classification has not yet been evaluated with solid synapomorphic characters. Thirty-one morphological species are currently recognized on the island of Crete and its satellite islets. Four of them (A. retusa, A. torticollis, A. jaeckeli, and A. teres) are distributed on the island of Dia (north of Crete); the first three are island endemics. Here, we combined mitochondrial and nuclear DNA information and Bayesian and Maximum Likelihood approaches to evaluate the phylogenetic relationships, and assess the genetic distinctiveness and cohesiveness of all described species of Dia Island. The produced phylogeny was not congruent with the morphological species, demonstrating a more complex pattern of speciation and diversification. Although each island endemic constitutes a monophyletic lineage, the number of island endemic species could be greater than the three currently recognized species so far (A. retusa, A. torticollis, and A. jaeckeli), since a newly discovered lineage (north-western part of the island), that morphologically differs from the populations of A. torticollis in the eastern part, and genetically is more closely related to A. jaeckeli, could be elevated to the species level. Considering the fourth species found on the island of Dia, A. teres is genetically highly variable, showing low geographic structuring due to either long-distance gene flow or retained ancestral polymorphisms, or a combination of both. Further work (analysis of more specimens and DNA data) both from Dia and Crete is indispensable in order to shed light on aspects of the evolutionary history of the genus in Dia.

In this study we investigate the evolutionary relationships of Scolopendra cingulata (Latreille, 1829) within insular Greece. Our main goal is to infer the time frame of the differentiation of the species in the study area. In this regard, sequence data originating from three mitochondrial genes are used to reconstruct the evolutionary history of 47 insular populations of S. cingulata from the Aegean archipelago. Within the phylogenetic framework and by implementing a relaxed molecular clock methodology, we infer the time estimates of separations of the S. cingulata lineages. The results of the phylogenetic analysis support the presence of three distinct S. cingulata groups in the region. The first group accommodates populations from the eastern Aegean islands, and is closely related to the second group that hosts mainly populations of northern and central Cyclades. The third group is composed of insular populations originating from southern Cyclades. Different temporal splitting scenarios have been evaluated. Based on the scenario strongly supported by the data, we propose a biogeographical scenario that could account for the contemporary distribution of the species' lineages. The splitting events of S. cingulata are estimated to have occurred within the late Miocene. The historical events of the last 13.77 Myr have shaped, through a series of mostly vicariant and dispersal incidents, the present-day biogeographical pattern of the species. © 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, 105, 507–521.

146..159 The present study article examines the shapes of centipede species-area relationships (SARs) in the Mediterranean islands, compares the results of the linear form of the power model between archipelagos, discusses biological significance of the power model parameters with other taxa on the Aegean archipelago, and tests for a significant small-island effect (SIE). We used 11 models to test the SARs and we compared the quality-of-fit of all candidate models. The power function ranked first and Z-values was in the range 0.106-0.334. We assessed the presence of SIEs by fitting both a continuous and discontinuous breakpoint regression model. The continuous breakpoint regression functions never performed much better than the closest discontinuous model as a predictor of centipede species richness. We suggest that the relatively low Z-values in our data partly reflect better dispersal abilities in centipedes than in other soil invertebrate taxa. Longer periods of isolation and more recent island formation may explain the somewhat lower constant c in the western Mediterranean islands compared to the Aegean islands. Higher breakpoint values in the western Mediterranean may also be a result of larger distance to the mainland and longer separation times. Despite the differences in the geological history and the idiosyncratic features of the main island groups considered, the overall results are quite similar and this could be assigned to the ability of centipedes to disperse across isolation barriers. © 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, 105, 146-159. ADDITIONAL KEYWORDS: Aegean archipelago - Akaike's information criterion - breakpoint regression models - Crete - Cyclades - Dodecanese - Italy - Sardinia - Sicily.

The species–area relationship (SAR) between different biological provinces is one of the most interesting, but least explored aspects of the well-known species–area pattern. Following the usage that a biological province is a region whose species have for the most part evolved within it, rather than immigrating from somewhere else, we propose that islands can be considered equivalent to biological provinces for single island endemic species (SIEs). Hence, analyses of the relationships between numbers of SIEs and island area can be used as model systems to explore the form of inter-provincial SARs. We analyzed 13 different data sets derived from 11 sources, using the power (log–log) model. Eleven of the SIE–area relationships were statistically significant, explaining high proportions of the variance in SIE numbers (R2 0.57–0.95). The z-values (slopes) of the statistically significant SIE–area relationships ranged from 0.47 to 1.13, with a mean value of 0.80 (SD±0.24). All the island systems in which SIE represent >50% of species exhibited z-values for the SARs of native species higher than those deemed typical of archipelagic SARs. The SIE–area slopes are quite similar to those previously calculated for inter-provincial SARs, indicating that, when speciation becomes the dominant process adding to the species richness of assemblages, high z-values should be anticipated, regardless of the biogeographical scale of the study system.

The land mollusc fauna of 1 km 2 of Cretan maquis was surveyed by sampling fourteen 400-m 2 plots in May 2001, and by resampling six of these in February 2002. Sampling methods were designed to resemble those used in similar surveys of 1-km 2 sites in tropical rainforests in Cameroon and Sabah. A total of 27 species were recorded for the site. Slugs and a semi-slug were found only in the 2002 survey. Individual plots were very similar in species richness and composition; the richest plot contained about 85% of the fauna recorded for the whole site. Overall densities were very high. This local homogeneity contrasts with marked heterogeneity over Crete as a whole. These results are contrasted with those from tropical forests, where individual plots vary considerably in richness and composition, where densities are lower and where the total site faunas are larger. Although there are problems associated with differing amounts of sampling error between studies, this contrast is striking and some possible causes are discussed. Further work in tropical forest on limestone may elucidate this.

The land snails of the genus Chilostoma Fitzinger, 1833 that includes, in Greece, the (sub)genera Cattania, Josephinella and Thiessea, are highly diversified and present high levels of endemism. However, their evolutionary history is unknown and their taxonomy is complex and continuously revised. The aim of this study is to investigate the phylogenetic relationships of the lineages of the genus Chilostoma distributed in Greece based on partial DNA sequences of two mitochondrial DNA (16S rRNA and COI) genes. Complete sequences of one nuclear gene (ITS1) representing the major mitochondrial lineages were also analyzed. The phylogenetic trees revealed three distinct major clades that correspond to the three (sub)genera. Several taxonomical incongruencies were made obvious, thus, raising questions about the “true” number of species in each clade, while rendering a taxonomic re-evaluation necessary. From a phylogeographic point of view, it seems that the three major phylogenetic clades were separated in the late Miocene. They started differentiating into distinct species during the Pliocene and Pleistocene through several vicariance and dispersal events.

The species of the genus Scolopendra Linnaeus, 1758 are very widely distributed in the Mediterranean region. Current knowledge is summarized, with references to material derived mainly from the well-explored islands of the Aegean Archipelago, several localities in continental Greece and old bibliographic reports. We suggest that Scolopendra species represent examples of both paradigms of historical biogeography, namely vicariance and dispersal. We propose that the dispersal routes of Scolopendra species in Greece were mainly influenced by late Miocene and upper Pleistocene palaeogeography. The formation of the Mid-Aegean trench (c. 12 – 9 Mya) considered as a remarkable geographical barrier between the Anatolian peninsula and mainland Greece, prevented the entry of certain Scolopendra species westwards. In total, five Scolopendra species have been recorded from mainland and insular Greece. A vicariance event that occurred in the area more than 17 Mya, when the Aegean region was part of a united landmass, better explains the biogeographical history of S. canidens. Cyclades harbours remnants of the ancient populations of S. canidens, whereas during the late Pleistocene (c. 400.000 21.000 ya) S. canidens was isolated in Dodecanese. S. cretica is the only endemic, being distributed in Crete and its adjacent islets. S. clavipes in E-Mediterranean and S. dalmatica in W-Mediterranean evolved from ancient canidens populations. S. cingulata entered central and southern Europe from the east (c. 20 – 11 Mya), while the formation of the Mid-Aegean trench (c. 12 – 9 Mya) prevented its entry in Crete.

This research aimed to study the land snails of three island groups (Skyros, Astypalaia, Kalymnos) in the Aegean Sea and the biogeographical patterns arising, with reference to the other Aegean islands. A total of 91 species was found on the 37 islands surveyed, with 89 being extant. For the majority of the islands the malacofauna is reported for the first time. Similarity indices, chorotypes and nestedness were studied for each of the island groups. The islands belonging to the same island group were clustered together, exhibiting a quite delimited malacofauna. The Mediterranean and Palaearctic elements dominate, with the Aegean element increasing in the Astypalaia group. The three island groups, despite their different geological histories and the different level of the present‐day geographical isolation, have been formed quite recently in geological time. This “recent” formation of the groups results in islands, especially the small ones, which still behave as parts of a continuous land mass. In the co...

In the present paper we study the biogeography of land snails in the Skyros archipelago (central Aegean) using both conventional species-area analysis and the newly-developed choros model. The choros model is a simple mathematical relationship, which analyses species richness as a function of area and of environmental heterogeneity, quantified by assessing the number of defined habitats present on each island. We surveyed land snails on 12 islands of the archipelago of Skyros in the central Aegean Sea (Greece). The different types of habitats were defined based on the ecology and biology of each species distributed in the archipelago. Forty-two land snail species were recorded living in 11 different habitat types. The z-values from both models, the choros and the classic species-area relationship, place the archipelago in the "within biogeographic province" category, mainly due to the recent formation of the archipelago. This recent formation resulted in a group of small islands still behaving as parts of a continuous landmass. The recorded extinction of land snails in the archipelago follows the general pattern of extinctions of this animal group in the Aegean area. The choros model gave a better fit to the data than the classic species-area model, indicating that the range of habitats available plays a significant role in determining faunal diversity independently of area. The availability of knowledge on the ecology of each species in most islands of the Aegean enabled us to recognise the key environmental features on which we based the definition of the habitat types. Such background knowledge is essential if island studies are to progress beyond the simple demonstration of a species! area relationship.